177 results on '"Monika Österberg"'
Search Results
2. Insights into spheroids formation in cellulose nanofibrils and Matrigel hydrogels using AFM-based techniques
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Roberta Teixeira Polez, Ngoc Huynh, Chris S. Pridgeon, Juan José Valle-Delgado, Riina Harjumäki, and Monika Österberg
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Cellulose nanofibrils ,Matrigel ,Spheroid formation ,Cell interactions ,Atomic force microscopy ,Cell adhesion molecules ,Medicine (General) ,R5-920 ,Biology (General) ,QH301-705.5 - Abstract
The recent FDA decision to eliminate animal testing requirements emphasises the role of cell models, such as spheroids, as regulatory test alternatives for investigations of cellular behaviour, drug responses, and disease modelling. The influence of environment on spheroid formation are incompletely understood, leading to uncertainty in matrix selection for scaffold-based 3D culture. This study uses atomic force microscopy-based techniques to quantify cell adhesion to Matrigel and cellulose nanofibrils (CNF), and cell-cell adhesion forces, and their role in spheroid formation of hepatocellular carcinoma (HepG2) and induced pluripotent stem cells (iPS(IMR90)-4). Results showed different cell behaviour in CNF and Matrigel cultures. Both cell lines formed compact spheroids in CNF but loose cell aggregates in Matrigel. Interestingly, the type of cell adhesion protein, and not the bond strength, appeared to be a key factor in the formation of compact spheroids. The gene expression of E- and N-cadherins, proteins on cell membrane responsible for cell-cell interactions, was increased in CNF culture, leading to formation of compact spheroids while Matrigel culture induced integrin-laminin binding and downregulated E-cadherin expression, resulting in looser cell aggregates. These findings enhance our understanding of cell-biomaterial interactions in 3D cultures and offer insights for improved 3D cell models, culture biomaterials, and applications in drug research.
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- 2024
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3. Combining Rigid Cellulose Nanocrystals and Soft Silk Proteins: Revealing Interactions and Alignment in Shear
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Ilona Leppänen, Suvi Arola, Alistair W. T. King, Miriam Unger, Hartmut Stadler, Gry Sofie Nissen, Charlotte Zborowski, Tommi Virtanen, Juha Salmela, Harri Setälä, Stephanie Lésage, Monika Österberg, and Tekla Tammelin
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alignment ,cellulose nanocrystals ,interactions ,regenerated silk fibroins ,silanization ,Physics ,QC1-999 ,Technology - Abstract
Abstract Natural materials, such as silk and cellulose, have an inspiring set of properties, which have evolved over hundreds of millions of years. In this study, cellulose nanocrystals (CNCs) and regenerated silk fibroin (RSF) are combined to evaluate their suitability for filament formation. This is assessed by tuning and characterizing the interactions between these two materials and finally by studying the alignment of the mixtures under shear. To modify the interactions between CNCs and silk, CNCs with varying surface functionalities (sulfate and/or aminosilane groups) are used. The interactions and compatibility of the two components are investigated using quartz crystal microbalance with dissipation monitoring (QCM‐D) and photothermal atomic force microscopy (AFM‐IR), which show that ionic interactions induce sufficient binding between the two components. Then, the alignment of the CNC and silk mixtures is evaluated by shear‐induced polarized light imaging, which indicates that silk can orientate with the CNCs when not covalently bound. Finally, the potential of the materials for filament formation is tentatively demonstrated using an industrial dry‐spinning environment, where CNCs are expected to bring order and alignment, whereas RSF provides soft and more mobile regions to further facilitate the alignment of the final filament structure.
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- 2023
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4. Synthesis of an Azide- and Tetrazine-Functionalized [60]Fullerene and Its Controlled Decoration with Biomolecules
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Vijay Gulumkar, Ville Tähtinen, Aliaa Ali, Jani Rahkila, Juan José Valle-Delgado, Antti Äärelä, Monika Österberg, Marjo Yliperttula, and Pasi Virta
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Chemistry ,QD1-999 - Published
- 2021
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5. Towards sustainable production and utilization of plant-biomass-based nanomaterials: a review and analysis of recent developments
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J. Y. Zhu, Umesh P. Agarwal, Peter N. Ciesielski, Michael E. Himmel, Runan Gao, Yulin Deng, Maria Morits, and Monika Österberg
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Lignin nanoparticles (LNPs) ,Cellulosic nanomaterials (CNMs) ,Cellulosic nano-whiskers (CNWs) ,Cell wall deconstruction ,Fibrillation ,Fuel ,TP315-360 ,Biotechnology ,TP248.13-248.65 - Abstract
Abstract Plant-biomass-based nanomaterials have attracted great interest recently for their potential to replace petroleum-sourced polymeric materials for sustained economic development. However, challenges associated with sustainable production of lignocellulosic nanoscale polymeric materials (NPMs) need to be addressed. Producing materials from lignocellulosic biomass is a value-added proposition compared with fuel-centric approach. This report focuses on recent progress made in understanding NPMs—specifically lignin nanoparticles (LNPs) and cellulosic nanomaterials (CNMs)—and their sustainable production. Special attention is focused on understanding key issues in nano-level deconstruction of cell walls and utilization of key properties of the resultant NPMs to allow flexibility in production to promote sustainability. Specifically, suitable processes for producing LNPs and their potential for scaled-up production, along with the resultant LNP properties and prospective applications, are discussed. In the case of CNMs, terminologies such as cellulose nanocrystals (CNCs) and cellulose nanofibrils (CNFs) used in the literature are examined. The term cellulose nano-whiskers (CNWs) is used here to describe a class of CNMs that has a morphology similar to CNCs but without specifying its crystallinity, because most applications of CNCs do not need its crystalline characteristic. Additionally, progress in enzymatic processing and drying of NPMs is also summarized. Finally, the report provides some perspective of future research that is likely to result in commercialization of plant-based NPMs.
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- 2021
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6. Durable Biopolymer Films From Lignin-Carbohydrate Complex Derived From a Pulp Mill Side Stream
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Brita Asikanius, Anna-Stiina Jääskeläinen, Hanna Koivula, Petri Oinonen, and Monika Österberg
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lignin-carbohydrate complex ,LCC ,biopolymer film ,lignocellulose biomass ,side stream valorization ,mechanical properties ,General Works - Abstract
Valorization of side streams offers novel types of raw materials to complement or replace synthetic and food-based alternatives in materials science, increasing profitability and decreasing the environmental impacts of biorefineries. Lignocellulose biomass contains lignin and carbohydrates that are covalently linked into lignin-carbohydrate complexes (LCCs). In biomass fractionation processes, these complexes are conventionally considered as waste, which hinders the biomass fractionation process, and they may solubilize into aqueous effluents. This study presents how LCCs, derived from pulp mill effluent, can be turned into valuable biopolymers for industrial polymer film applications. Free-standing composite films containing hydroxyethyl cellulose (HEC) and LCCs with varying molar mass, charge density and lignin/hemicellulose ratio were prepared to study the effect of LCC amount on mechanical properties and oxygen permeability. Increasing the LCC content increased the yield point and Young’s modulus of the films. Breaking strain measurements revealed a non-linear correlation with the LCC concentration for the samples with higher lignin than hemicellulose content. The addition of LCC enhanced oxygen barrier properties of HEC films significantly even at high relative humidity. The present research demonstrates how a currently underutilized fraction of the biorefinery side stream has the potential to be valorized as a biopolymer in industrial applications, for example as a barrier film for paper and board packaging.
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- 2021
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7. Bioactive Films from Willow Bark Extract and Nanocellulose Double Network Hydrogels
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Tia Lohtander, Rafael Grande, Monika Österberg, Päivi Laaksonen, and Suvi Arola
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cellulose nanofibrils ,wood-bark extracts ,double network hydrogels ,bioactive (poly)phenols ,barrier properties ,polyphenols ,Technology ,Chemical technology ,TP1-1185 - Abstract
In nature, the protection of sensitive components from external threats relies on the combination of physical barriers and bioactive secondary metabolites. Polyphenols and phenols are active molecules that protect organisms from physical and chemical threats such as UV irradiation and oxidative stress. The utilization of biopolymers and natural bioactive phenolic components as protective coating layers in packaging solutions would enable easier recyclability of materials and greener production process compared with the current plastic-based products. Herein, we produce a fully wood-based double network material with tunable bioactive and optical properties consisting of nanocellulose and willow bark extract. Willow bark extract, embedded in nanocellulose, was cross-linked into a polymeric nanoparticle network using either UV irradiation or enzymatic means. Based on rheological analysis, atomic force microscopy, antioxidant activity, and transmittance measurements, the cross-linking resulted in a double network gel with enhanced rheological properties that could be casted into optically active films with good antioxidant properties and tunable oxygen barrier properties. The purely biobased, sustainably produced, bioactive material described here broadens the utilization perspectives for wood-based biomass, especially wood-bark extractives. This material has potential in applications where biodegradability, UV shielding, and antioxidant properties of hydrogels or thin films are needed, for example in medical, pharmaceutical, food, and feed applications, but also as a functional barrier coating in packaging materials as the hydrogel properties are transferred to the casted and dried films.
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- 2021
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8. Cytokeratin 5 determines maturation of the mammary myoepithelium
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Vivi Deckwirth, Eeva Kaisa Rajakylä, Sandhanakrishnan Cattavarayane, Anna Acheva, Niccole Schaible, Ramaswamy Krishnan, Juan José Valle-Delgado, Monika Österberg, Pia Björkenheim, Antti Sukura, and Sari Tojkander
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Cell Biology ,Developmental Biology ,Biophysics ,Science - Abstract
Summary: At invasion, transformed mammary epithelial cells expand into the stroma through a disrupted myoepithelial (ME) cell layer and basement membrane (BM). The intact ME cell layer has thus been suggested to act as a barrier against invasion. Here, we investigate the mechanisms behind the disruption of ME cell layer. We show that the expression of basal/ME proteins CK5, CK14, and α-SMA altered along increasing grade of malignancy, and their loss affected the maintenance of organotypic 3D mammary architecture. Furthermore, our data suggests that loss of CK5 prior to invasive stage causes decreased levels of Zinc finger protein SNAI2 (SLUG), a key regulator of the mammary epithelial cell lineage determination. Consequently, a differentiation bias toward luminal epithelial cell type was detected with loss of mature, α-SMA-expressing ME cells and reduced deposition of basement membrane protein laminin-5. Therefore, our data discloses the central role of CK5 in mammary epithelial differentiation and maintenance of normal ME layer.
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- 2021
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9. Spatially confined lignin nanospheres for biocatalytic ester synthesis in aqueous media
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Mika Henrikki Sipponen, Muhammad Farooq, Jari Koivisto, Alessandro Pellis, Jani Seitsonen, and Monika Österberg
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Science - Abstract
Development of biocatalysts that mimic compartmentalized reactions in cells has been cumbersome due to the lack of low-cost materials and associated technologies. Here the authors show that cationic lignin nanospheres function as activating anchors for hydrolases, and enable aqueous ester synthesis by forming spatially confined biocatalysts.
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- 2018
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10. Aqueous Ammonia Pre-treatment of Wheat Straw: Process Optimization and Broad Spectrum Dye Adsorption on Nitrogen-Containing Lignin
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Mika Henrikki Sipponen and Monika Österberg
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biorefinery ,environment ,lignocellulose ,plant biomass ,sustainable materials ,water purification ,Chemistry ,QD1-999 - Abstract
Biorefineries need cost-efficient pretreatment processes that overcome the recalcitrance of plant biomass, while providing feasible valorization routes for lignin. Here we assessed aqueous ammonia for the separation of lignin from hydrothermally pretreated wheat straw prior to enzymatic saccharification. A combined severity parameter was used to determine the effects of ammonia concentration, treatment time and temperature on compositional and physicochemical changes [utilizing elemental analysis, cationic dye adsorption, FTIR spectroscopy, size-exclusion chromatography (SEC), and 31P nuclear magnetic resonance (NMR) spectroscopy] as well as enzymatic hydrolysability of straw. Pretreatment at the highest severity (20% NH3, 160°C) led to the maximum hydrolysability of 71% in a 24 h reaction time at an enzyme dosage of 15 FPU/g of pretreated straw. In contrast, hydrolysabilities remained low regardless of the severity when a low cellulase dosage was used, indicating competitive adsorption of cellulases on nitrogen-containing lignin. In turn, our results showed efficient adsorption of cationic, anionic and uncharged organic dyes on nitrogen-containing lignin, which opens new opportunities in practical water remediation applications.
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- 2019
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11. Natural Shape-Retaining Microcapsules With Shells Made of Chitosan-Coated Colloidal Lignin Particles
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Tao Zou, Mika H. Sipponen, and Monika Österberg
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lignin nanoparticles ,chitosan ,thin film coating ,Pickering emulsion ,microcapsule ,drug delivery ,Chemistry ,QD1-999 - Abstract
Thin film coating of charged nanoparticles with oppositely charged polymers is an efficient and straightforward way for surface modification, but synthetic polyelectrolytes should be replaced by abundant biopolymers. In this study a thin film of chitosan was adsorbed onto colloidal lignin particles (CLPs) that were then systematically studied for olive oil stabilization with an objective to develop shape-retaining microcapsules that comprised of only renewable biomaterials. Full surface coverage was achieved with merely 5 wt% of chitosan relative to the dry weight of CLPs, reversing their surface charge from negative to positive. Such modification rendered the chitosan-coated particles excellent stabilizers for forming Pickering emulsions with olive oil. The emulsion droplets could be further stabilized by sodium triphosphate that provided ionic intra- and inter-particle cross-linking of the chitosan corona on the CLPs. Following the optimum conditions, the non-cross-linked microcapsules exhibited a strong stability against coalescence and the electrostatically stabilized ones additionally retained their shape upon drying and rewetting. Non-cross-linked microcapsules were used to demonstrate encapsulation and rapid release of ciprofloxacin as a model lipophilic drug in aqueous media. Overall, the combination of antimicrobial chitosan and antioxidative lignin nanoparticles hold unprecedented opportunities as biocompatible and biodegradable materials for controlled drug delivery.
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- 2019
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12. Colloidal Lignin Particles as Adhesives for Soft Materials
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Maija-Liisa Mattinen, Guillaume Riviere, Alexander Henn, Robertus Wahyu N. Nugroho, Timo Leskinen, Outi Nivala, Juan José Valle-Delgado, Mauri A. Kostiainen, and Monika Österberg
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lignin ,nanoparticle ,protein ,nanocellulose ,fibril ,enzyme ,heat ,self-assembly ,cross-link ,Chemistry ,QD1-999 - Abstract
Lignin has interesting functionalities to be exploited in adhesives for medicine, foods and textiles. Nanoparticles (NPs) < 100 nm coated with poly (L-lysine), PL and poly(L-glutamic acid) PGA were prepared from the laccase treated lignin to coat nanocellulose fibrils (CNF) with heat. NPs ca. 300 nm were prepared, β-casein coated and cross-linked with transglutaminase (Tgase) to agglutinate chamois. Size exclusion chromatography (SEC) and Fourier-transform infrared (FTIR) spectroscopy were used to characterize polymerized lignin, while zeta potential and dynamic light scattering (DLS) to ensure coating of colloidal lignin particles (CLPs). Protein adsorption on lignin was studied by quartz crystal microbalance (QCM). Atomic force microscopy (AFM) was exploited to examine interactions between different polymers and to image NPs with transmission electron microscopy (TEM). Tensile testing showed, when using CLPs for the adhesion, the stress improved ca. 10 and strain ca. 6 times compared to unmodified Kraft. For the β-casein NPs, the values were 20 and 8, respectively, and for the β-casein coated CLPs between these two cases. When NPs were dispersed in adhesive formulation, the increased Young’s moduli confirmed significant improvement in the stiffness of the joints over the adhesive alone. Exploitation of lignin in nanoparticulate morphology is a potential method to prepare bionanomaterials for advanced applications.
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- 2018
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13. Emulsion Stabilization with Functionalized Cellulose Nanoparticles Fabricated Using Deep Eutectic Solvents
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Jonna Ojala, Miikka Visanko, Ossi Laitinen, Monika Österberg, Juho Antti Sirviö, and Henrikki Liimatainen
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cellulose nanocrystals (CNCs) ,cellulose nanofibrils (CNFs) ,nanoparticle ,stabilization ,o/w emulsion ,surface-functionalization ,deep eutectic solvent (DES) ,Organic chemistry ,QD241-441 - Abstract
In this experiment, the influence of the morphology and surface characteristics of cellulosic nanoparticles (i.e., cellulose nanocrystals [CNCs] and cellulose nanofibers [CNFs]) on oil-in-water (o/w) emulsion stabilization was studied using non-modified or functionalized nanoparticles obtained following deep eutectic solvent (DES) pre-treatments. The effect of the oil-to-water ratio (5, 10, and 20 wt.-% (weight percent) of oil), the type of nanoparticle, and the concentration of the particles (0.05⁻0.2 wt.-%) on the oil-droplet size (using laser diffractometry), o/w emulsion stability (via analytical centrifugation), and stabilization mechanisms (using field emission scanning electron microscopy with the model compound—i.e., polymerized styrene in water emulsions) were examined. All the cellulosic nanoparticles studied decreased the oil droplet size in emulsion (sizes varied from 22.5 µm to 8.9 µm, depending on the nanoparticle used). Efficient o/w emulsion stabilization against coalescence and an oil droplet-stabilizing web-like structure were obtained only, however, with surface-functionalized CNFs, which had a moderate hydrophilicity level. CNFs without surface functionalization did not prevent either the coalescence or the creaming of emulsions, probably due to the natural hydrophobicity of the nanoparticles and their instability in water. Moderately hydrophilic CNCs, on the other hand, distributed evenly and displayed good interaction with both dispersion phases. The rigid structure of CNCs meant, however, that voluminous web structures were not formed on the surface of oil droplets; they formed in flat, uniform layers instead. Consequently, emulsion stability was lower with CNCs, when compared with surface-functionalized CNFs. Tunable cellulose nanoparticles can be used in several applications such as in enhanced marine oil response.
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- 2018
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14. LAYER STRUCTURES FORMED BY SILICA NANOPARTICLES AND CELLULOSE NANOFIBRILS WITH CATIONIC POLYACRYLAMIDE (C-PAM) ON CELLULOSE SURFACE AND THEIR INFLUENCE ON INTERACTIONS
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Jani Salmi, Tiina Nypelö, Monika Österberg, and Janne Laine
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Adsorption ,Surface force ,Nanoparticle ,Cellulose nanofibril ,Polyelectrolyte ,Multilayer ,AFM ,QCM-D ,Biotechnology ,TP248.13-248.65 - Abstract
A quartz crystal microbalance with dissipation monitoring (QCM-D) was used to study the adsorption of the layer formed by silica nanoparticles (SNP) and cellulose nanofibrils (NFC) together with cationic polyacrylamide (C-PAM) on cellulose surface, accompanied by use of atomic force microscope (AFM) to study the interactions between cellulose surfaces. The purpose was to understand the multilayer build-up compared to complex structure adsorption. The layer thickness and consequently also the repulsion between surfaces increased with each addition step during layer formation in the SNP-C-PAM systems, whereas the second addition of C-PAM decreased the repulsion in the case of NFC-C-PAM multilayer formation. An exceptionally high repulsion between surfaces was observed when nanofibrillar cellulose was added. This together with the extremely high dissipation values recorded with QCM-D indicated that nanofibrillar cellulose formed a loose and thick layer containing a lot of water. The multilayer systems formed fully and uniformly covered the surfaces. Silica nanoparticles were able to penetrate inside the loose C-PAM structure due to their small size. In contrast, NFC formed individual layers between C-PAM layers. The complex of C-PAM and SNP formed only a partly covered surface, leading to long-ranged pull-off force. This might explain the good flocculation properties reported for polyelectrolyte-nanoparticle systems.
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- 2009
15. EFFECT OF POLYMER ADSORPTION ON CELLULOSE NANOFIBRIL WATER BINDING CAPACITY AND AGGREGATION
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Susanna Ahola, Petri Myllytie, Monika Österberg, Tuija Teerinen, and Janne Laine
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Adsorption ,Polymer ,Cellulose nanofibril ,MFC ,QCM-D ,SPR ,CLSM ,Biotechnology ,TP248.13-248.65 - Abstract
Polymer adsorption on cellulose nanofibrils and the effect on nanofibril water binding capacity were studied using cellulose nanofibril films together with quartz crystal microbalance with dissipation (QCM-D) and surface plasmon resonance (SPR). The experiments were performed in the immersed state, and special attention was paid to the effect of polymer properties on the water content and viscoelastic properties of the polymer/fibril layer. The dry mass of the adsorbed polymers was determined using SPR. The type of the adsorbed polymer strongly affected the water content and viscoelastic properties of the nanofibril film. The adsorption of a highly charged flocculating polymer, PDADMAC, caused dehydration of the film, which was also detected as nanofibril film stiffening. The adsorption of xyloglucan introduced a dispersing effect to the nanofibril film, which was detected as a loosening and softening of the nanofibril/polymer layer. A dispersing effect was also achieved with carboxymethyl cellulose (CMC), but CMC did not adsorb irreversibly on the nanofibril surfaces. In addition to the nanofibril film studies, the effect of polymer adsorption on cellulose nanofibril suspension aggregation was demonstrated using confocal laser scanning microscopy (CLSM). Xyloglucan was shown to open the nanofibril aggregate structures and act as a dispersing agent, whereas the other polymers studied did not have as significant an effect on aggregation.
- Published
- 2008
16. Hybrid films from cellulose nanomaterials—properties and defined optical patterns
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Ilona Leppänen, Ari Hokkanen, Monika Österberg, Mika Vähä-Nissi, Ali Harlin, Hannes Orelma, VTT Technical Research Centre of Finland, Department of Bioproducts and Biosystems, Aalto-yliopisto, and Aalto University
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Nanocellulose film ,Optical properties ,Polymers and Plastics ,CNF ,Compression ,CNC ,Hybrid - Abstract
Polymer composites with nanocellulose as the reinforcing agent often lack good compatibility between the two components. In this study, we have combined cellulose nanofibrils (CNFs) and cellulose nanocrystals (CNCs) in different ratios to create all-cellulose films consisting of entirely discrete nanocellulose objects that complement each other. Then further, by applying the controlled dissolution concept we were able to create defined optical patterns on the films. The films consisting of 50% CNCs showed equivalent mechanical and barrier properties when compared to the pure CNF film. In addition, the incorporation of CNCs enabled tuning of the films’ optical properties. To modify this film further, we prepared specific patterns on the film by controlled dissolution by impregnating the films with N-methylmorpholine-N-oxide (NMMO) followed by heat treatment and pressure. Mechanical testing and optical measurements of the patterned films showed the effect of the dissolved cellulose regions on the film properties. The controlled dissolution of the films increased the tensile strength of the films, however, the strain was decreased quite significantly. Altogether, the CNF/CNC hybrid films combine both nanomaterials’ good properties. Cellulose nanofibrils have film-forming ability and incorporation of CNCs can further tune the optical, mechanical, and barrier properties, to optimize the films for varying applications such as optical sensors and packaging materials. Graphical abstract
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- 2022
17. Biobased Nanomaterials─The Role of Interfacial Interactions for Advanced Materials
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Muhammad Farooq, Alexander Henn, Monika Österberg, Juan José Valle-Delgado, Bioproduct Chemistry, Department of Bioproducts and Biosystems, Aalto-yliopisto, and Aalto University
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General Chemistry - Abstract
Österberg, Farooq, and Henn acknowledge Academy of Finland’s Flagship Program (project numbers 318890 and 318891, Competence Center for Materials Bioeconomy, FinnCERES), for funding. We thank Dr. Heidi Henrickson for her excellent help with proofreading, list of abbreviations, and guidance. This review presents recent advances regarding biomass-based nanomaterials, focusing on their surface interactions. Plant biomass-based nanoparticles, like nanocellulose and lignin from industry side streams, hold great potential for the development of lightweight, functional, biodegradable, or recyclable material solutions for a sustainable circular bioeconomy. However, to obtain optimal properties of the nanoparticles and materials made thereof, it is crucial to control the interactions both during particle production and in applications. Herein we focus on the current understanding of these interactions. Solvent interactions during particle formation and production, as well as interactions with water, polymers, cells and other components in applications, are addressed. We concentrate on cellulose and lignin nanomaterials and their combination. We demonstrate how the surface chemistry of the nanomaterials affects these interactions and how excellent performance is only achieved when the interactions are controlled. We furthermore introduce suitable methods for probing interactions with nanomaterials, describe their advantages and challenges, and introduce some less commonly used methods and discuss their possible applications to gain a deeper understanding of the interfacial chemistry of biobased nanomaterials. Finally, some gaps in current understanding and interesting emerging research lines are identified.
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- 2023
18. In Situ Adsorption of Red Onion (Allium cepa) Natural Dye on Cellulose Model Films and Fabrics Exploiting Chitosan as a Natural Mordant
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Rafael Grande, Riikka Räisänen, Jinze Dou, Satu Rajala, Kiia Malinen, Paula A. Nousiainen, Monika Österberg, Helsinki Institute of Sustainability Science (HELSUS), The Academic Outreach Network, Maker@STEAM, Department of Education, Maker culture, Design learning and Technology (MaDe), Department of Bioproducts and Biosystems, University of Helsinki, School services, CHEM, Bioproduct Chemistry, Aalto-yliopisto, and Aalto University
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Anthocyanins ,Flavonoids ,Identification ,General Chemical Engineering ,Cultivars ,Nanofibrils ,Wool ,116 Chemical sciences ,516 Educational sciences ,General Chemistry ,Cotton fabrics ,L - Abstract
Funding Information: This work was funded by the BioColour project supported by the Strategic Research Council at the Academy of Finland (Funding Nos. 327178 and 327195). The authors are also grateful for support from the FinnCERES Materials Bioeconomy Ecosystem. Ira Smal is acknowledged for assistance in laboratory work. Publisher Copyright: © 2023 The Authors. Published by American Chemical Society. Synthetic dyes and chemicals create an enormous impact on environmental pollution both in textile manufacturing and after the product’s lifetime. Biobased plant-derived colorants and mordants have great potential for the development of more sustainable textile dyeing processes. Colorants isolated from biomass residues are renewable, biodegradable, and usually less harmful than their synthetic counterparts. Interestingly, they may also bring additional functions to the materials. However, the extraction and purification of the biocolorants from biomass as well as their dyeing efficiency and color fastness properties require a more thorough examination. Here, we extracted red onion (Allium cepa) skins to obtain polyphenolic flavonoids and anthocyanins as biocolorants, characterized the chemical composition of the mixture, and used a quartz crystal microbalance and thin films of cellulose nanofibrils to study the adsorption kinetics of dyes onto cellulose substrates in situ. The effect of different mordants on the adsorption behavior was also investigated. Comparison of these results with conventional dyeing experiments of textiles enabled us to determine the interaction mechanism of the dyes with substrates and mordants. Chitosan showed high potential as a biobased mordant based both on its ability to facilitate fast adsorption of polyphenols to cellulose and its ability to retain the purple color of the red onion dye (ROD) in comparison to the metal mordants FeSO4 and alum. The ROD also showed excellent UV-shielding efficiency at low concentrations, suggesting that biocolorants, due to their more complex composition compared to synthetic ones, can have multiple actions in addition to providing aesthetics.
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- 2023
19. Interfacial catalysis and lignin nanoparticles for strong fire- and water-resistant composite adhesives
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K. Alexander Henn, Susanna Forssell, Antti Pietiläinen, Nina Forsman, Ira Smal, Paula Nousiainen, Rahul Prasad Bangalore Ashok, Pekka Oinas, Monika Österberg, Department of Bioproducts and Biosystems, Department of Chemical and Metallurgical Engineering, Plant design, Aalto-yliopisto, and Aalto University
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Environmental Chemistry ,Pollution - Abstract
openaire: EC/H2020/869993/EU//IMPRESS Wood is increasingly replacing concrete to reduce CO2 emissions in buildings, but fossil-based adhesives are still being used in wood panels. Epoxidized lignin adhesives could be a potential replacement, but their preparation has so far required low-molecular weight lignin and long reaction times. Here we show a new efficient method to produce epoxidized kraft lignin (EKL) from regular kraft lignin by using interfacial catalysis. We demonstrate that EKL combined with biocolloids in the form of lignin nanoparticles (LNPs) produces a strong adhesive comparable to commercially available ones when cross-linked at 130-160 °C for only 3-5 minutes. The adhesive was free of phenol or formaldehyde, had a lignin content of over 80% and still showed impressive wet strength and incredible thermal stability. The process was shown to be scalable and environmentally more sustainable than resins from fossil-based feedstock or currently available ones from renewable resources.
- Published
- 2022
20. Affinity of Keratin Peptides for Cellulose and Lignin:A Fundamental Study toward Advanced Bio-Based Materials
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Emmi-Maria Nuutinen, Juan José Valle-Delgado, Miriam Kellock, Muhammad Farooq, Monika Österberg, School common, CHEM, Department of Bioproducts and Biosystems, VTT Technical Research Centre of Finland, Aalto-yliopisto, and Aalto University
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Surface Properties ,Quartz Crystal Microbalance Techniques ,Electrochemistry ,Keratins ,General Materials Science ,Adsorption ,Surfaces and Interfaces ,Cellulose ,Peptides ,Condensed Matter Physics ,Lignin ,Spectroscopy - Abstract
Publisher Copyright: © 2022 The Authors. Published by American Chemical Society. Keratin is a potential raw material to meet the growing demand for bio-based materials with special properties. Keratin can be obtained from feathers, a by-product from the poultry industry. One approach for keratin valorization is to use the protein to improve the properties of already existing cellulose and lignin-based materials to meet the requirements for replacing fossil-based plastics. To ensure a successful combination of keratin with lignocellulosic building blocks, keratin must have an affinity to these substrates. Hence, we used quartz crystal microbalance with a dissipation monitoring (QCM-D) technique to get a detailed understanding of the adsorption of keratin peptides onto lignocellulosic substrates and how the morphology of the substrate, pH, ionic strength, and keratin properties affected the adsorption. Keratin was fractionated from feathers with a scalable and environmentally friendly deep eutectic solvent process. The keratin fraction used in the adsorption studies consisted of different sized keratin peptides (about 1-4 kDa), which had adopted a random coil conformation as observed by circular dichroism (CD). Measuring keratin adsorption to different lignocellulosic substrates by QCM-D revealed a significant affinity of keratin peptides for lignin, both as smooth films and in the form of nanoparticles but only a weak interaction between cellulose and keratin. Systematic evaluation of the effect of surface, media, and protein properties enabled us to obtain a deeper understanding of the driving force for adsorption. Both the structure and size of the keratin peptides appeared to play an important role in its adsorption. The keratin-lignin combination is an attractive option for advanced material applications. For improved adsorption on cellulose, modifications of either keratin or cellulose would be required.
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- 2022
21. Colloidal Lignin Particles and Epoxies for Bio-Based, Durable, and Multiresistant Nanostructured Coatings
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Nina Forsman, Tao Zou, Karl Alexander Henn, Monika Österberg, Bioproduct Chemistry, Department of Bioproducts and Biosystems, Aalto-yliopisto, and Aalto University
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Diglycidyl ether ,Materials science ,Light ,Surface Properties ,Abrasion (mechanical) ,nanostructured ,lignin ,Glyceryl Ethers ,02 engineering and technology ,engineering.material ,010402 general chemistry ,01 natural sciences ,epoxy ,Contact angle ,chemistry.chemical_compound ,Coating ,Materials Testing ,lignin nanoparticles ,Lignin ,General Materials Science ,Colloids ,chemistry.chemical_classification ,Temperature ,Water ,Polymer ,Epoxy ,Pinus ,021001 nanoscience & nanotechnology ,Wood ,0104 chemical sciences ,Surface coating ,Chemical engineering ,chemistry ,bio-based ,surface coating ,visual_art ,engineering ,visual_art.visual_art_medium ,Epoxy Compounds ,Nanoparticles ,0210 nano-technology ,Hydrophobic and Hydrophilic Interactions ,Research Article - Abstract
Authors Alexander Henn, Nina Forsman, and Monika sterberg declare that they have a financial interest in the development and commercialization of the research presented in this article. Aalto University has filed a provisional patent application (FI 20205555). Funding Information: KAH, NF and TZ thank Business Finland for financing via the LignoSphere project (project number: 2117744). This work was also a part of the Academy of Finland's Flagship Programme under projects No. 318890 and 318891 (Competence Center for Materials Bioeconomy, FinnCERES), financial support for KAH. The authors also thank Dr. Heidi Henrickson for her excellent help with proofreading and guidance, Mr. Rob Hindley for his generous help with linguistic support and proofreading, and Valeria Azovskaya for her helpful advice regarding the graphical material. Publisher Copyright: © 2021 The Authors. Published by American Chemical Society. There is a need for safe and sustainable alternatives in the coating industry. Bio-based coatings are interesting in this perspective. Although various oils and waxes have been used as traditional wood coatings, they often lack sufficient durability. Lignin is an abundant natural polyphenol that can be used to cure epoxies, but its poor water solubility has impeded the use of unmodified lignin in coatings in the past. To address this issue, water-dispersible colloidal lignin particles (CLPs) and an epoxy compound, glycerol diglycidyl ether (GDE), were used to prepare multiprotective bio-based surface coatings. With the GDE/CLP ratios of 0.65 and 0.52 g/g, the cured CLP-GDE films became highly resistant to abrasion and heat. When applied as a coating on wooden substrates, the particulate morphology enabled effective protection against water, stains, and sunlight with very thin layers (less than half the weight of commercial coatings) while retaining the wood's breathability excellently. Optimal hydrophobicity was reached with a coat weight of 6.9 g(CLP)/m2, resulting in water contact angle values of up to 120°. Due to their spherical shape and chemical structure, the CLPs acted as both a hardener and a particulate component in the coating, which removed the need for an underlying binding polymer matrix. Light interferometry measurements showed that while commercial polymeric film-forming coatings smoothened the substrate noticeably, the particulate morphology retained the substrate's roughness in lightweight coatings, allowing for a high water contact angle. This work presents new strategies for lignin applications in durable particulate coatings and their advantages compared to both currently used synthetic and bio-based coatings.
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- 2021
22. Lignin-Based Porous Supraparticles for Carbon Capture
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Tao Zou, Bruno D. Mattos, Mika Henrikki Sipponen, Ling Wang, Maryam Borghei, Bin Zhao, Orlando J. Rojas, Leena-Sisko Johansson, Johanna Majoinen, Monika Österberg, Department of Bioproducts and Biosystems, Stockholm University, Bio-based Colloids and Materials, Aalto-yliopisto, and Aalto University
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Materials science ,Heteroatom ,General Physics and Astronomy ,Nanoparticle ,chemistry.chemical_element ,02 engineering and technology ,carbon supraparticles ,010402 general chemistry ,01 natural sciences ,Article ,chemistry.chemical_compound ,Adsorption ,Desorption ,General Materials Science ,Cellulose ,Carbonization ,cellulose nanofibrils ,General Engineering ,Sorption ,021001 nanoscience & nanotechnology ,CO2 capture ,evaporation-induced self-assembly ,0104 chemical sciences ,chemistry ,Chemical engineering ,lignin particles ,COcapture ,0210 nano-technology ,Carbon - Abstract
openaire: EC/H2020/788489/EU//BioELCell Funding Information: We are thankful for funding support from Commission H2020 program ERC Advanced Grant (No. 788489, BioELCell), the Canada Excellence Research Chair initiative and the Canada Foundation for Innovation (CFI). We are grateful for the support by the FinnCERES Materials Bioeconomy Ecosystem. B. Zhao is grateful for the financial support from the China Scholarship Council (Project #201702640280) and NordForsk Project 82214 “High-Value Products from Lignin”. The authors thank L. Greca for providing the lignin microparticles and for discussions on their oxidative thermostabilization. The authors thank I. Schlapp-Hackl for assisting in the installation of the CO adsorption device. We also acknowledge J. Campbell for XPS measurements. 2 Publisher Copyright: © 2021 The Authors. Published by American Chemical Society. Copyright: Copyright 2021 Elsevier B.V., All rights reserved. Multiscale carbon supraparticles (SPs) are synthesized by soft-templating lignin nano- and microbeads bound with cellulose nanofibrils (CNFs). The interparticle connectivity and nanoscale network in the SPs are studied after oxidative thermostabilization of the lignin/CNF constructs. The carbon SPs are formed by controlled sintering during carbonization and develop high mechanical strength (58 N·mm-3) and surface area (1152 m2·g-1). Given their features, the carbon SPs offer hierarchical access to adsorption sites that are well suited for CO2 capture (77 mg CO2·g-1), while presenting a relatively low pressure drop (∼33 kPa·m-1 calculated for a packed fixed-bed column). The introduced lignin-derived SPs address the limitations associated with mass transport (diffusion of adsorbates within channels) and kinetics of systems that are otherwise based on nanoparticles. Moreover, the carbon SPs do not require doping with heteroatoms (as tested for N) for effective CO2 uptake (at 1 bar CO2 and 40 °C) and are suitablefor regeneration, following multiple adsorption/desorption cycles. Overall, we demonstrate porous SP carbon systems of low cost (precursor, fabrication, and processing) and superior activity (gas sorption and capture).
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- 2021
23. Skin and bubble formation in films made of methyl nanocellulose, hydrophobically modified ethyl(hydroxyethyl)cellulose and microfibrillated cellulose
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Maria Morits, Johanna Lyytikäinen, Isto Heiskanen, Monika Österberg, Kaj Backfolk, LUT University, Department of Bioproducts and Biosystems, Stora Enso, Aalto-yliopisto, and Aalto University
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chemistry.chemical_classification ,Barrier ,Hydrophobically modified ethyl(hydroxyethyl)cellulose ,Materials science ,Polymers and Plastics ,MFC ,02 engineering and technology ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Methyl nanocellulose ,01 natural sciences ,0104 chemical sciences ,Nanomaterials ,Nanocellulose ,Oxygen transmission rate ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,Methyl cellulose ,Amphiphile ,Thin film ,Cellulose ,0210 nano-technology - Abstract
The use of nanomaterials and polymers from renewable resources is important in the search for sustainable alternatives to plastic-based packaging materials and films. In this work, self-supporting thin films prepared from derivatized and non-derivatized nanocellulose and cellulose derivatives were studied. The effect of drying temperature on the film-forming behavior of compositions comprising hydrophobically modified ethyl(hydroxyethyl)cellulose (EHEC), native microfibrillated cellulose (MFC) and nanocellulose made from methyl cellulose was determined. The interaction between the components was assessed from viscosity measurements made at different temperatures, the result being linked to a thermal-dependent association during liquid evaporation, and the subsequent barrier and film-forming properties. The effect of temperature on suspensions was clearly different between the materials, confirming that there were differences in interaction and association between EHEC–MFC and methyl nanocellulose–MFC compositions. The amphiphilic EHEC affected both the suspension homogeneity and the film properties. Air bubbles were formed under certain conditions and composition particularly in MFC films, dependent on the drying procedure. The presence of air bubbles did not affect the oxygen transmission rate or the oil and grease resistance. An increasing amount of MFC improved the oxygen barrier properties of the films.
- Published
- 2020
24. High-resolution 3D printing of xanthan gum/nanocellulose bio-inks
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Hossein Baniasadi, Erfan Kimiaei, Roberta Teixeira Polez, Rubina Ajdary, Orlando J. Rojas, Monika Österberg, Jukka Seppälä, Department of Chemical and Metallurgical Engineering, Bioproduct Chemistry, Bio-based Colloids and Materials, Polymer technology, Department of Bioproducts and Biosystems, Aalto-yliopisto, and Aalto University
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Excipients ,Tissue Engineering ,Tissue Scaffolds ,Structural Biology ,Polysaccharides, Bacterial ,Printing, Three-Dimensional ,Humans ,Hydrogels ,Ink ,General Medicine ,Cellulose ,Molecular Biology ,Biochemistry - Abstract
The authors would like to acknowledge the Academy of Finland funding; No. 327248 (ValueBiomat) and 327865 (Bioeconomy). This work was a part of the Academy of Finland's Flagship Programme under Projects No. 318890 and 318891 (Competence Center for Materials Bioeconomy, FinnCERES). The authors would also like to thank the Biohybrid Materials Research Group (Aalto University) for providing the HepG2 cells. The current study provides a comprehensive rheology study and a survey on direct ink writing of xanthan gum/cellulose nanocrystal (XG/CNC) bio-inks for developing 3D geometries that mimic soft tissue engineering scaffolds' physical and mechanical properties. The presence of CNC was found to be a critical prerequisite for the printability of XG bio-inks; accordingly, the hybrid XG/CNC bio-inks revealed the excellent viscoelastic properties that enabled precise control of hydrogel shaping and printing of lattice structures composed of up to eleven layers with high fidelity and fair resolution without any deformation after printing. The lyophilized 3D scaffolds presented a porous structure with open and interconnected pores and a porosity higher than 70%, vital features for tissue engineering scaffolds. Moreover, they showed a relatively high swelling of approximately 11 g/g, facilitating oxygen and nutrient exchange. Furthermore, the elastic and compressive moduli of the scaffolds that enhanced significantly upon increasing CNC content were in the range of a few kPa, similar to soft tissues. Finally, no significant cell cytotoxicity was observed against human liver cancer cells (HepG2), highlighting the potential of these developed 3D printed scaffolds for soft tissue engineering applications.
- Published
- 2022
25. Lightweight lignocellulosic foams for thermal insulation
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Tia Lohtander, Reima Herrala, Päivi Laaksonen, Sami Franssila, Monika Österberg, Bioproduct Chemistry, Multifunctional Materials Design, Häme University of Applied Sciences, Microfabrication, Department of Bioproducts and Biosystems, Department of Chemistry and Materials Science, Aalto-yliopisto, and Aalto University
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Camouflage ,Polymers and Plastics ,Surfactant ,SDG 7 - Affordable and Clean Energy ,Cellulose ,Foam ,Lignin ,Nanocellulose - Abstract
Lisään tiedoston kun VoR on julkaistu Acknowledgments The authors thank Marja Ka¨rkka¨inen for providing the bleached pulp and Tuyen Nguyen for providing cellulose nanofibrils. We are grateful for the support by the FinnCERES Materials Bioeconomy Ecosystem and this work made use of Aalto University Bioeconomy Facilities. Funding Open Access funding provided by Aalto University. This work was funded by The Scientific Advisory Board for Defence (MATINE, 2500 M-0110). Foams are mainly composed of dispersed gas trapped in a liquid or solid phase making them lightweight and thermally insulating materials. Additionally, they are applicable for large surfaces, which makes them attractive for thermal insulation. State-of-the-art thermally insulating foams are made of synthetic polymeric materials such as polystyrene. This work focuses on generating foam from surfactants and renewable lignocellulosic materials for thermally insulating stealth material. The effect of two surfactants (sodium dodecyl sulphate (SDS) and polysorbate (T80)), two cellulosic materials (bleached pulp and nanocellulose), and lignin on the foaming and stability of foam was investigated using experimental design and response surface methodology. The volume-optimized foams determined using experimental design were further studied with optical microscopy and infrared imaging. The results of experimental design, bubble structure of foams, and observations of their thermal conductivity showed that bleached pulpfoam made using SDS as surfactant produced the highest foam volume, best stability, and good thermal insulation. Lignin did not improve the foaming or thermal insulation properties of the foam, but it was found to improve the structural stability of foam and brought natural brown color to the foam. Both wet and dry lignocellulosic foams provided thermal insulation comparable to dry polystyrene foam.
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- 2022
26. AFM Force Spectroscopy Reveals the Role of Integrins and Their Activation in Cell–Biomaterial Interactions
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Yan-Ru Lou, Riina Harjumäki, Xue Zhang, Marjo Yliperttula, Muhammad Farooq, Robertus Wahyu N. Nugroho, Juan José Valle-Delgado, Monika Österberg, Division of Pharmaceutical Biosciences, Tissue engineering for drug research, Drug Research Program, Biopharmaceutics Group, Department of Bioproducts and Biosystems, Bioproduct Chemistry, Bio-based Colloids and Materials, University of Helsinki, Aalto-yliopisto, and Aalto University
- Subjects
integrin ,Integrin ,FIBRONECTIN ,Biomedical Engineering ,force spectroscopy ,02 engineering and technology ,ADHESION ,Divalent ,Biomaterials ,03 medical and health sciences ,atomic force microscope ,human pluripotent stem cells ,MODULATION ,Cell adhesion ,Induced pluripotent stem cell ,030304 developmental biology ,CALIBRATION ,chemistry.chemical_classification ,laminin-521 ,0303 health sciences ,biology ,SURFACES ,Biochemistry (medical) ,cellulose nanofibrils ,Force spectroscopy ,MICROSCOPY ,General Chemistry ,Adhesion ,colloidal probe microscopy ,QUANTIFICATION ,NANOFIBRILLAR CELLULOSE HYDROGEL ,021001 nanoscience & nanotechnology ,Fibronectin ,human hepatocarcinoma cells ,chemistry ,216 Materials engineering ,LIGAND-BINDING ,biology.protein ,Biophysics ,MORPHOLOGY ,221 Nano-technology ,0210 nano-technology ,Intracellular - Abstract
Transmembrane protein integrins play a key role in cell adhesion. Cell-biomaterial interactions are affected by integrin expression and conformation, which are actively controlled by cells. Although integrin structure and function have been studied in detail, quantitative analyses of integrin-mediated cell-biomaterial interactions are still scarce. Here, we have used atomic force spectroscopy to study how integrin distribution and activation (via intracellular mechanisms in living cells or by divalent cations) affect the interaction of human pluripotent stem cells (WA07) and human hepatocarcinoma cells (HepG2) with promising biomaterials-human recombinant laminin-521 (LN-521) and cellulose nanofibrils (CNF). Cell adhesion to LN-521-coated probes was remarkably influenced by cell viability, divalent cations, and integrin density in WA07 colonies, indicating that specific bonds between LN-521 and activated integrins play a significant role in the interactions between LN-521 and HepG2 and WA07 cells. In contrast, the interactions between CNF and cells were nonspecific and not influenced by cell viability or the presence of divalent cations. These results shed light on the underlying mechanisms of cell adhesion, with direct impact on cell culture and tissue engineering applications.
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- 2020
27. Spherical lignin particles: a review on their sustainability and applications
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Bruno D. Mattos, Orlando J. Rojas, Monika Österberg, Mika Henrikki Sipponen, Bioproduct Chemistry, Bio-based Colloids and Materials, Department of Bioproducts and Biosystems, Aalto-yliopisto, and Aalto University
- Subjects
Materials science ,Nanotechnology ,CONTROLLED-RELEASE ,02 engineering and technology ,SURFACE-ROUGHNESS ,010402 general chemistry ,01 natural sciences ,7. Clean energy ,Dispersant ,COLLOIDAL SPHERES ,KRAFT LIGNIN ,chemistry.chemical_compound ,Environmental Chemistry ,Lignin ,DRUG-DELIVERY ,SUNSCREEN PERFORMANCE ,Spherical shape ,Kraft lignin ,chemistry.chemical_classification ,SODIUM LIGNOSULFONATE ,Biomolecule ,INDUSTRIAL APPLICATIONS ,021001 nanoscience & nanotechnology ,Pollution ,0104 chemical sciences ,chemistry ,13. Climate action ,Sustainability ,PICKERING EMULSIONS ,SLOW-RELEASE ,0210 nano-technology - Abstract
openaire: EC/H2020/788489/EU//BioELCell There is an increased interest in renewable carbon as a source of materials, where lignin is expected to play a prominent role. This stems, partially, from new regulations aiming to achieve a cleaner and safer environment. Lignin, as a polyaromatic plant-derived biomolecule, is not only abundant but widely accessible in industrial streams. Due to recent developments in production scalability as well as promising application prospects, nanoscaled lignin particles have recently generated interest in the research and industrial communities. This review describes the main routes to prepare spherical lignin particles, highlighting aspects associated to their shape and topology as well as performance. We discuss the use of spherical lignin particles as dispersants and in the formulation of coatings, adhesives and composites, focusing on the advantages of the spherical shape and nanoscaled size. The state of the particles is furthermore compared in terms of their applicability in dry and wet forms. Finally, we discuss the sustainability, stability and degradation of lignin particles, which are issues that are critically important for any prospective use.
- Published
- 2020
28. Synthesis of an Azide-and Tetrazine-Functionalized [60]Fullerene and Its Controlled Decoration with Biomolecules
- Author
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Vijay Gulumkar, Ville Tähtinen, Aliaa Ali, Jani Rahkila, Juan José Valle-Delgado, Antti Äärelä, Monika Österberg, Marjo Yliperttula, Pasi Virta, University of Turku, Åbo Akademi University, Department of Bioproducts and Biosystems, University of Helsinki, Aalto-yliopisto, Aalto University, Division of Pharmaceutical Biosciences, Biopharmaceutics Group, and Drug Research Program
- Subjects
CATALYZED ALKYNE-AZIDE ,010405 organic chemistry ,General Chemical Engineering ,MALEIMIDE ,General Chemistry ,HEXAKIS-ADDUCTS ,010402 general chemistry ,01 natural sciences ,SCAFFOLDS ,Article ,0104 chemical sciences ,Chemistry ,317 Pharmacy ,CLICK CHEMISTRY ,CYCLOOCTYNE ,C-60 ,FULLERENE ,QD1-999 - Abstract
Funding Information: V.G. and P.V. acknowledge Academy of Finland’s Project No. 308931. J.J.V.D. and M.Ö. acknowledge Academy of Finland’s Flagship Programme under Project Nos. 318890 and 318891 (Competence Center for Materials Bioeconomy, FinnCERES). M.Y. acknowledges Academy of Finland’s Flagship Programme under Project No. 337430 (Gene, Cell and Nano Therapy Competence Cluster for the Treatment of Chronic Diseases, GeneCellNano). Publisher Copyright: © 2021 The Authors. Published by American Chemical Society. Bingel cyclopropanation between Buckminster fullerene and a heteroarmed malonate was utilized to produce a hexakis-functionalized C60 core, with azide and tetrazine units. This orthogonally bifunctional C60 scaffold can be selectively one-pot functionalized by two pericyclic click reactions, that is, inverse electron-demand Diels-Alder and azide-alkyne cycloaddition, which with appropriate ligands (monosaccharides, a peptide and oligonucleotides tested) allows one to control the assembly of heteroantennary bioconjugates.
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- 2022
29. Lignin Nanoparticles-Based Antibacterial Coatings for Development of Antimicrobial Surfaces
- Author
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Maria Morits, Roberta Teixeira Polez, Satu Salo, Petri Widsten, Kristoffer Meinander, Donika Morina, Stina Grönqvist, Monika Österberg, Virtanen, Atte, Torvinen, Katariina, and Vepsäläinen, Jessica
- Subjects
SDG 3 - Good Health and Well-being - Abstract
Antibiotic resistance development in bacteria is a serious threat to human health all over the world. One of the common ways of transmission of bacteria is contact with contaminated surfaces. Antimicrobial surfaces are promising solution for containment of spread of infection. Use of bio- based and biodegradable materials for antimicrobial coatings of disposable products are of great interest due to their lower environmental impact in comparison with synthetic compounds. In this study filter paper samples were uniformly coated with different amounts of softwood Kraft lignin nanoparticles using spraying or immersion methods. Presence of the particles on the samples’ surfaces were confirmed by Scanning Electron microscopy (SEM). Surface density of the particles on the surface were determined by weighing and by X-ray Photoelectron Spectroscopy (XPS). The Minimum Inhibitory Concentration (MIC) of LNPs dispersions for Staphylococcus aureus was 0.16 wt.-% in 24h contact time. The LNPs’ coatings demonstrated antimicrobial properties against methicillin-resistant Staphylococcus aureus (MRSA) which makes LNPs promising bio- based antimicrobial agent for development of antimicrobial surfaces.
- Published
- 2022
30. 3D printing and properties of cellulose nanofibrils-reinforced quince seed mucilage bio-inks
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Jukka Seppälä, Erfan Kimiaei, Monika Österberg, Zahraalsadat Madani, Orlando J. Rojas, Roberta Teixeira Polez, Hossein Baniasadi, Department of Chemical and Metallurgical Engineering, Bioproduct Chemistry, Multifunctional Materials Design, Bio-based Colloids and Materials, Polymer technology, Department of Bioproducts and Biosystems, Department of Chemistry and Materials Science, Aalto-yliopisto, and Aalto University
- Subjects
Engineering ,Chemical Phenomena ,Nanofibers ,Library science ,Biochemistry ,Plant Mucilage ,chemistry.chemical_compound ,Structural Biology ,Cell Line, Tumor ,Humans ,Cellulose ,Rosaceae ,Molecular Biology ,Tissue Scaffolds ,business.industry ,Spectrum Analysis ,Hydrogels ,General Medicine ,chemistry ,Mucilage ,Hepg2 cells ,Printing, Three-Dimensional ,Rheology ,business ,Porosity - Abstract
The authors would like to acknowledge the Academy of Finland funding; No. 327248 (ValueBiomat) and 327865 (Bioeconomy). This work was a part of the Academy of Finland's Flagship Programme under Projects No. 318890 and 318891 (Competence Center for Materials Bioeconomy, FinnCERES). The authors would also like to thank Ms. Marja Kärkkäinen for providing TEMPO-CNF and the Biohybrid Materials Research Group (Aalto University) for providing the HepG2 cells. Plant-based hydrogels have attracted great attention in biomedical fields since they are biocompatible and based on natural, sustainable, cost-effective, and widely accessible sources. Here, we introduced new viscoelastic bio-inks composed of quince seed mucilage and cellulose nanofibrils (QSM/CNF) easily extruded into 3D lattice structures through direct ink writing in ambient conditions. The QSM/CNF inks enabled precise control on printing fidelity where CNF endowed objects with shape stability after freeze-drying and with suitable porosity, water uptake capacity, and mechanical strength. The compressive and elastic moduli of samples produced at the highest CNF content were both increased by ~100% (from 5.1 ± 0.2 kPa and 32 ± 1 kPa to 10.7 ± 0.5 and 64 ± 2 kPa, respectively). These values ideally matched those reported for soft tissues; accordingly, the cell compatibility of the printed samples was evaluated against HepG2 cells (human liver cancer). The results confirmed the 3D hydrogels as being non-cytotoxic and suitable to support attachment, survival, and proliferation of the cells. All in all, the newly developed inks allowed sustainable 3D bio-hydrogels fitting the requirements as scaffolds for soft tissue engineering.
- Published
- 2021
31. Experimental and Simulation Study of the Solvent Effects on the Intrinsic Properties of Spherical Lignin Nanoparticles
- Author
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Aleksi Zitting, Mikhail Balakshin, Monika Österberg, Anna Maria Elert, Dorothee Silbernagl, Juan José Valle-Delgado, Paavo A. Penttilä, Mohammad Khavani, Maisa Vuorte, Maria Sammalkorpi, Nonappa Nonappa, Tao Zou, Tampere University, Materials Science and Environmental Engineering, Department of Bioproducts and Biosystems, Soft Materials Modelling, Wood Material Science, Bundesanstalt für Materialforschung und -prüfung, Lignin Chemistry, Department of Chemistry and Materials Science, Bioproduct Chemistry, Aalto-yliopisto, and Aalto University
- Subjects
Materials science ,Nanoparticle ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Lignin ,Article ,Nanomaterials ,chemistry.chemical_compound ,Molecular dynamics ,X-Ray Diffraction ,Scattering, Small Angle ,Materials Chemistry ,Physical and Theoretical Chemistry ,Porosity ,Tetrahydrofuran ,Aqueous solution ,Small-angle X-ray scattering ,221 Nanotechnology ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Surfaces, Coatings and Films ,chemistry ,Chemical engineering ,216 Materials engineering ,8. Economic growth ,Solvents ,Nanoparticles ,Solvent effects ,0210 nano-technology - Abstract
This work made use of Aalto University Bioeconomy Facilities and OtaNano─Nanomicroscopy Center Facilities. Bin Zhao is thanked for conducting the N2 adsorption–desorption experiments. T.Z. acknowledges funding from the Novo Nordisk Foundation (SUSCELL project, Reference Number: NNF17OC0027658), M.V. acknowledges funding from Fortum and Neste Foundation (grant no. 20200079), P.P. acknowledges funding from the Academy of Finland (grant no. 315768), and M.S. acknowledges funding from the Academy of Finland (grant no. 309324). Computational resources by CSC IT Centre for Science, Finland, and RAMI─RawMatTERS Finland Infrastructure are gratefully acknowledged. The authors are also grateful for the support by the FinnCERES Materials Bioeconomy Ecosystem and Photonics Research and Innovation (PREIN) flagship. Spherical lignin nanoparticles (LNPs) fabricated via nanoprecipitation of dissolved lignin are among the most attractive biomass-derived nanomaterials. Despite various studies exploring the methods to improve the uniformity of LNPs or seeking more application opportunities for LNPs, little attention has been given to the fundamental aspects of the solvent effects on the intrinsic properties of LNPs. In this study, we employed a variety of experimental techniques and molecular dynamics (MD) simulations to investigate the solvent effects on the intrinsic properties of LNPs. The LNPs were prepared from softwood Kraft lignin (SKL) using the binary solvents of aqueous acetone or aqueous tetrahydrofuran (THF) via nanoprecipitation. The internal morphology, porosity, and mechanical properties of the LNPs were analyzed with electron tomography (ET), small-angle X-ray scattering (SAXS), atomic force microscopy (AFM), and intermodulation AFM (ImAFM). We found that aqueous acetone resulted in smaller LNPs with higher uniformity compared to aqueous THF, mainly ascribing to stronger solvent–lignin interactions as suggested by MD simulation results and confirmed with aqueous 1,4-dioxane (DXN) and aqueous dimethyl sulfoxide (DMSO). More importantly, we report that both LNPs were compact particles with relatively homogeneous density distribution and very low porosity in the internal structure. The stiffness of the particles was independent of the size, and the Young’s modulus was in the range of 0.3–4 GPa. Overall, the fundamental understandings of LNPs gained in this study are essential for the design of LNPs with optimal performance in applications.
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- 2021
32. Lignin Nanoparticles as an Interfacial Modulator in Tough and Multi‐Resistant Cellulose–Polycaprolactone Nanocomposites Based on a Pickering Emulsions Strategy (Adv. Mater. Interfaces 27/2022)
- Author
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Erfan Kimiaei, Muhammad Farooq, Rafael Grande, Kristoffer Meinander, and Monika Österberg
- Subjects
Mechanics of Materials ,Mechanical Engineering - Published
- 2022
33. Model Cellulosic Surfaces
- Author
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Maren Roman, Maren Roman, Eero Kontturi, Monika Österberg, Emily D. Cranston, Derek G. Gray, Emily D. Cranston, Derek G. Gray, Véronique Aguié-Béghin, Michaël Molinari, Arayik Hambardzumyan, Laurence Foulon, Youssef Habibi, Thomas Heim, Ralph Blossey, Roger Douillard, Ufuk Karabiyik, Min Mao, Maren and Maren Roman, Maren Roman, Eero Kontturi, Monika Österberg, Emily D. Cranston, Derek G. Gray, Emily D. Cranston, Derek G. Gray, Véronique Aguié-Béghin, Michaël Molinari, Arayik Hambardzumyan, Laurence Foulon, Youssef Habibi, Thomas Heim, Ralph Blossey, Roger Douillard, Ufuk Karabiyik, Min Mao, Maren
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- 2010
34. Toward waste valorization by converting bioethanol production residues into nanoparticles and nanocomposite films
- Author
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Guillaume Riviere, Pascal Pandard, Xun Liao, Stéphanie Baumberger, Florian Pion, Guy Marlair, Hanna Koivula, Thangavelu Jayabalan, Muhammad Farooq, Monika Österberg, Mika Henrikki Sipponen, Department of Food and Nutrition, Helsinki Institute of Sustainability Science (HELSUS), Aalto University, Institut Jean-Pierre Bourgin (IJPB), AgroParisTech-Université Paris-Saclay-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), University of Helsinki, Institut National de l'Environnement Industriel et des Risques (INERIS), Ecole Polytechnique Fédérale de Lausanne (EPFL), Quantis, H2020 BBI-JU, FinnCERES Materials Bioeconomy Ecosystem, Aalto University Bioeconomy Facilities, European Project: 720303,Zelcor, Helsingin yliopisto = Helsingfors universitet = University of Helsinki, Bioproduct Chemistry, Université Paris-Saclay, Institut national de l'environnement industriel et des risques, Department of Bioproducts and Biosystems, and Aalto-yliopisto
- Subjects
[SDV.BIO]Life Sciences [q-bio]/Biotechnology ,LIGNIN NANOPARTICLES ,FABRICATION ,Nanoparticle ,02 engineering and technology ,Raw material ,010402 general chemistry ,7. Clean energy ,01 natural sciences ,NANOSTRUCTURES ,Industrial and Manufacturing Engineering ,Nanomaterials ,[SPI.MAT]Engineering Sciences [physics]/Materials ,BIOMASS ,MECHANISMS ,CUO ,chemistry.chemical_compound ,Hydrolysis ,Life cycle assessment ,lifecycle assessment ,ANTIOXIDANT ,ZNO ,Lignin ,lignin nanoparticles ,WATER ,General Materials Science ,Ecotoxicity ,Cellulose ,[SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics ,Waste Management and Disposal ,biorefinery ,Nanocomposite ,Renewable Energy, Sustainability and the Environment ,ecotoxicity ,cellulose nanofibrils ,Lignocellulosic nanofibrils ,CELLULOSE NANOFIBRILS ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,lignocellulosic nanofibrils ,Biorefinery ,Cellulose fiber ,chemistry ,Chemical engineering ,13. Climate action ,221 Nano-technology ,0210 nano-technology - Abstract
A “waste-valorization” approach was developed to transform recalcitrant hydrolysis lignin (HL) from second-generationbioethanol productioninto multifunctional bio-based products. The hydrolysis lignin (HL) was extracted with aqueousacetone, yielding two fractions enriched in lignin and cellulose, respectively. The soluble hydrolysis lignin (SHL) was converted into anionic and cationic colloidal lignin particles (CLPs and c-CLPs). The insoluble cellulose-rich fraction was transformed intolignocellulosicnanofibrils that were further combined with CLPs or c-CLPs to obtainnanocomposite filmswithtailored mechanical properties,oxygen permeabilityand antioxidant properties. To enable prospective applications of lignin in nanocomposite films and beyond, CLPs and c-CLPs were also produced from a soda lignin (SL) and the influence of the lignin type on the particle size and ecotoxicity was evaluated. Finally, the carbon footprint of the entire process from hydrolysis lignin to films was assessed and an integration to industrial scale was considered to reduce the energy consumption. While most previous work utilizes purified lignin and pristine and often purified cellulose fibers to produce nanomaterials, this work provides aproof of conceptfor utilizing the recalcitrant lignin-rich side stream of thebioethanolprocess as raw material for functional nanomaterials and renewable composites.
- Published
- 2021
35. Towards sustainable production and utilization of plant-biomass-based nanomaterials: a review and analysis of recent developments
- Author
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Peter N. Ciesielski, Michael E. Himmel, Junyong Zhu, Runan Gao, Yulin Deng, Maria Morits, Umesh P. Agarwal, and Monika Österberg
- Subjects
Engineering ,Biomass ,Lignocellulosic biomass ,Nanotechnology ,02 engineering and technology ,Review ,Management, Monitoring, Policy and Law ,010402 general chemistry ,01 natural sciences ,Applied Microbiology and Biotechnology ,Commercialization ,chemistry.chemical_compound ,TP315-360 ,Cellulose ,Lignin nanoparticles (LNPs) ,Cellulosic nano-whiskers (CNWs) ,Flexibility (engineering) ,Renewable Energy, Sustainability and the Environment ,business.industry ,021001 nanoscience & nanotechnology ,Fuel ,0104 chemical sciences ,Cell wall deconstruction ,General Energy ,Deconstruction (building) ,chemistry ,Cellulosic ethanol ,Sustainability ,Fibrillation ,Cellulosic nanomaterials (CNMs) ,0210 nano-technology ,business ,TP248.13-248.65 ,Biotechnology - Abstract
Plant-biomass-based nanomaterials have attracted great interest recently for their potential to replace petroleum-sourced polymeric materials for sustained economic development. However, challenges associated with sustainable production of lignocellulosic nanoscale polymeric materials (NPMs) need to be addressed. Producing materials from lignocellulosic biomass is a value-added proposition compared with fuel-centric approach. This report focuses on recent progress made in understanding NPMs—specifically lignin nanoparticles (LNPs) and cellulosic nanomaterials (CNMs)—and their sustainable production. Special attention is focused on understanding key issues in nano-level deconstruction of cell walls and utilization of key properties of the resultant NPMs to allow flexibility in production to promote sustainability. Specifically, suitable processes for producing LNPs and their potential for scaled-up production, along with the resultant LNP properties and prospective applications, are discussed. In the case of CNMs, terminologies such as cellulose nanocrystals (CNCs) and cellulose nanofibrils (CNFs) used in the literature are examined. The term cellulose nano-whiskers (CNWs) is used here to describe a class of CNMs that has a morphology similar to CNCs but without specifying its crystallinity, because most applications of CNCs do not need its crystalline characteristic. Additionally, progress in enzymatic processing and drying of NPMs is also summarized. Finally, the report provides some perspective of future research that is likely to result in commercialization of plant-based NPMs.
- Published
- 2021
36. Lignin nanoparticles modified with tall oil fatty acid for cellulose functionalization
- Author
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Monika Österberg, Géza R. Szilvay, Arja Paananen, Ville Liljeström, Eva-Lena Hult, Hanna-Leena Alakomi, Kalle Lintinen, Miriam Kellock, Miikka Lievonen, Mauri A. Kostiainen, Harri Setälä, VTT Technical Research Centre of Finland, Department of Applied Physics, Department of Bioproducts and Biosystems, Bioproduct Chemistry, Biohybrid Materials, Aalto-yliopisto, and Aalto University
- Subjects
ADSORPTION ,Polymers and Plastics ,Starch ,lignin ,METHYL-METHACRYLATE ,chemistry.chemical_compound ,ALKYD RESINS ,ANTIOXIDANT ,Lignin ,SOFTWOOD ,Cellulose ,allylation ,chemistry.chemical_classification ,DERIVATIVES ,Tall oil ,FRACTIONATION ,Fatty acid ,KRAFT ,Antimicrobial ,cellulose ,chemistry ,STARCH ,Surface modification ,nanoparticles ,GRAFTING EFFICIENCY ,fatty acid ,Kraft paper ,Nuclear chemistry - Abstract
In this study, tall oil fatty acid ester of softwood kraft lignin (TOFA-L) was used to prepare TOFA lignin nanoparticles (TLNP) in water. The average diameters for two prepared TLNPs in 0.1 mg/ml concentration were 140 nm and 160 nm. TLNPs were attached covalently onto modified and unmodified cellulose fibres to form an antimicrobial composite material. The modified cellulose fibres contained reactive allylic double bonds with a degree of substitution of 0.05. The antimicrobial properties of both TLNPs and TLNP coated fibres (TLNP-C) were studied against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa using silver nanospheres (average size 10 nm) and Lignoboost lignin particles with 300 and 400 nm sizes as references. Antimicrobial activity of the samples was stronger against Gram-positive S. aureus cells than against Gram-negative target microbes E. coli and P. aeruginosa.
- Published
- 2019
37. Surface Engineered Biomimetic Inks Based on UV Cross-Linkable Wood Biopolymers for 3D Printing
- Author
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Yongchao Zhang, Xue Zhang, Fang Cheng, Xiaoju Wang, Monika Österberg, Chunlin Xu, Peiru Yang, Otto Långvik, Stefan Willför, Wenyang Xu, Materials Chemistry of Cellulose, Department of Bioproducts and Biosystems, Åbo Akademi University, Aalto-yliopisto, and Aalto University
- Subjects
biomedical applications ,Materials science ,Ultraviolet Rays ,Nanofibers ,3D printing ,Context (language use) ,Nanotechnology ,02 engineering and technology ,mechanical properties ,010402 general chemistry ,Methacrylate ,01 natural sciences ,Mannans ,galactoglucomannan methacrylate (GGMMA) ,chemistry.chemical_compound ,Tissue engineering ,Biomimetic Materials ,General Materials Science ,Hemicellulose ,Cellulose ,ta216 ,business.industry ,UV cross-linking ,Adhesion ,021001 nanoscience & nanotechnology ,Wood ,0104 chemical sciences ,chemistry ,Printing, Three-Dimensional ,Self-healing hydrogels ,Methacrylates ,Ink ,0210 nano-technology ,business ,cellulose nanofibrils (CNFs) ,Research Article - Abstract
Owing to their superior mechanical strength and structure similarity to the extracellular matrix, nanocelluloses as a class of emerging biomaterials have attracted great attention in three-dimensional (3D) bioprinting to fabricate various tissue mimics. Yet, when printing complex geometries, the desired ink performance in terms of shape fidelity and object resolution demands a wide catalogue of tunability on the material property. This paper describes surface engineered biomimetic inks based on cellulose nanofibrils (CNFs) and cross-linkable hemicellulose derivatives for UV-aided extrusion printing, being inspired by the biomimetic aspect of intrinsic affinity of heteropolysaccharides to cellulose in providing the ultrastrong but flexible plant cell wall structure. A facile aqueous-based approach was established for the synthesis of a series of UV cross-linkable galactoglucomannan methacrylates (GGMMAs) with tunable substitution degrees. The rapid gelation window of the formulated inks facilitates the utilization of these wood-based biopolymers as the feeding ink for extrusion-based 3D printing. Most importantly, a wide and tunable spectrum ranging from 2.5 to 22.5 kPa of different hydrogels with different mechanical properties could be achieved by varying the substitution degree in GGMMA and the compositional ratio between GGMMA and CNFs. Used as the seeding matrices in the cultures of human dermal fibroblasts and pancreatic tumor cells, the scaffolds printed with the CNF/GGMMA inks showed great cytocompatibility as well as supported the matrix adhesion and proliferative behaviors of the studied cell lines. As a new family of 3D printing feedstock materials, the CNF/GGMMA ink will broaden the map of bioinks, which potentially meets the requirements for a variety of in vitro cell-matrix and cell-cell interaction studies in the context of tissue engineering, cancer cell research, and high-throughput drug screening.
- Published
- 2019
38. A fast method to prepare mechanically strong and water resistant lignocellulosic nanopapers
- Author
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Monika Österberg, Miikka Visanko, Jatin Sethi, Juho Antti Sirviö, University of Oulu, Department of Bioproducts and Biosystems, Aalto-yliopisto, and Aalto University
- Subjects
Thermal properties ,Materials science ,Polymers and Plastics ,HIGH TOUGHNESS ,Modulus ,FIBER ,Dewatering ,02 engineering and technology ,FILMS ,010402 general chemistry ,Water resistance ,01 natural sciences ,Contact angle ,chemistry.chemical_compound ,Materials Chemistry ,Lignin ,Fiber ,Cellulose ,Composite material ,ta216 ,CRYSTALLITE SIZE ,Organic Chemistry ,Hybrid nanopapers ,CELLULOSE NANOFIBRILS ,BARRIER ,021001 nanoscience & nanotechnology ,Environmentally friendly ,THERMAL-DECOMPOSITION ,TRANSPARENT ,0104 chemical sciences ,Membrane ,Wood nanofibres ,chemistry ,HYDROPHOBIC CELLULOSE ,0210 nano-technology ,Cellulose nanofibres ,LIGNIN - Abstract
This study covers a green method to prepare hybrid lignocellulosic nanopapers by combining wood nanofibres (WNFs) and cellulose nanofibres (CNFs). The WNFs and CNFs behave synergistically to compensate for the drawbacks of each other resulting in enhanced hybrid nanopapers. The draining time of hybrid nanopapers was improved by up to 75% over CNF nanopaper, and the mechanical properties, modulus, strength and elongation, were respectively improved up to 35%, 90% and 180% over WNF nanopaper. Additionally, the water resistance of hybrid nanopapers was considerably improved with a water contact angle of 95°; the neat CNF nanopaper had a contact angle of 52°. The morphology of nanopapers, studied by electron microscopy, indicated that lignin acts as a matrix, which binds the nanofibres together and makes them impervious to external environmental factors, such as high humidity. The reported hybrid nanopapers are 100% bio-based, prepared by a simple and environmentally friendly processing route. Reported hybrid nanopapers can be used in novel applications such as gas barrier membranes and printable electronics.
- Published
- 2019
39. Quantifying the interactions between biomimetic biomaterials – collagen I, collagen IV, laminin 521 and cellulose nanofibrils – by colloidal probe microscopy
- Author
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Marjo Yliperttula, Xue Zhang, Robertus Wahyu N. Nugroho, Monika Österberg, Yan-Ru Lou, Riina Harjumäki, Juan José Valle-Delgado, Tissue engineering for drug research, Division of Pharmaceutical Biosciences, Faculty of Pharmacy, Drug Research Program, Biopharmaceutics Group, Department of Bioproducts and Biosystems, University of Helsinki, Aalto-yliopisto, and Aalto University
- Subjects
PROTEOGLYCAN ,116 Chemical sciences ,Composite number ,Nanofibers ,MICROENVIRONMENT ,Biocompatible Materials ,02 engineering and technology ,01 natural sciences ,MOLECULES ,3D cell culture ,Colloid and Surface Chemistry ,Tissue engineering ,Microscopy ,010304 chemical physics ,HYDROGEL ,Biomaterial ,MECHANICAL-PROPERTIES ,Surfaces and Interfaces ,General Medicine ,Adhesion ,021001 nanoscience & nanotechnology ,Colloidal probe technique ,317 Pharmacy ,Collagen ,AFM-colloidal probe technique ,0210 nano-technology ,Biotechnology ,Collagen Type IV ,Materials science ,Surface forces ,Surface Properties ,ta221 ,Nanotechnology ,ORGANIZATION ,FILMS ,Collagen Type I ,Adsorption ,0103 physical sciences ,Humans ,CELL ,Physical and Theoretical Chemistry ,Cellulose ,Tissue Engineering ,Surface force ,MODEL ,ATOMIC-FORCE MICROSCOPE ,216 Materials engineering ,Cellulose nanofibrils ,Laminin - Abstract
Biomaterials of different nature have been and are widely studied for various biomedical applications. In many cases, biomaterial assemblies are designed to mimic biological systems. Although biomaterials have been thoroughly characterized in many aspects, not much quantitative information on the molecular level interactions between different biomaterials is available. That information is very important, on the one hand, to understand the properties of biological systems and, on the other hand, to develop new composite biomaterials for special applications. This work presents a systematic, quantitative analysis of self- and cross-interactions between films of collagen I (Col I), collagen IV (Col IV), laminin (LN-521), and cellulose nanofibrils (CNF), that is, biomaterials of different nature and structure that either exist in biological systems (e.g., extracellular matrices) or have shown potential for 3D cell culture and tissue engineering. Direct surface forces and adhesion between biomaterials-coated spherical micro-particles and flat substrates were measured in phosphate-buffered saline using an atomic force microscope and the colloidal probe technique. Different methods (Langmuir-Schaefer deposition, spin-coating, or adsorption) were applied to completely coat the flat substrates and the spherical micro particles with homogeneous biomaterial films. The adhesion between biomaterials films increased with the time that the films were kept in contact. The strongest adhesion was observed between Col IV films, and between Col IV and LN-521 films after 30 s contact time. In contrast, low adhesion was measured between CNF films, as well as between CNF and LN-521 films. Nevertheless, a good adhesion between CNF and collagen films (especially Col I) was observed. These results increase our understanding of the structure of biological systems and can support the design of new matrices or scaffolds where different biomaterials are combined for diverse biological or medical applications.
- Published
- 2019
40. Tuning the functional properties of lignocellulosic films by controlling the molecular and supramolecular structure of lignin
- Author
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Stéphanie Baumberger, Amel Majira, Laurence Foulon, Miguel Pernes, Elise Gerbin, Monika Österberg, Carlos Marcuello, Bernard Kurek, A Gainvors-Claisse, David Crônier, Blandine Godon, Yves-Michel Frapart, Betty Cottyn, Véronique Aguié-Béghin, Guillaume Riviere, Université de Reims Champagne-Ardenne, Bioproduct Chemistry, Université de Paris, Université Paris-Saclay, Department of Bioproducts and Biosystems, Aalto-yliopisto, Aalto University, Fractionnement des AgroRessources et Environnement (FARE), Université de Reims Champagne-Ardenne (URCA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Aalto University School of Science and Technology [Aalto, Finland], Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques (LCBPT - UMR 8601), Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Institut Jean-Pierre Bourgin (IJPB), AgroParisTech-Université Paris-Saclay-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), European Project: 720303,Zelcor, Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), H2020 BBI-JU, ANR Institut Carnot 3BCar, European FEDER Programme, and Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)
- Subjects
[SDV.BIO]Life Sciences [q-bio]/Biotechnology ,[SDV]Life Sciences [q-bio] ,Composite number ,02 engineering and technology ,Microscopy, Atomic Force ,Biochemistry ,Oligomer ,Lignin ,Antioxidants ,law.invention ,[SPI.MAT]Engineering Sciences [physics]/Materials ,chemistry.chemical_compound ,Structural Biology ,law ,Spectroscopy, Fourier Transform Infrared ,Electron paramagnetic resonance ,0303 health sciences ,Antioxidant and antibacterial properties ,General Medicine ,Free Radical Scavengers ,Phenoxy radicals ,021001 nanoscience & nanotechnology ,Anti-Bacterial Agents ,Intercellular Signaling Peptides and Proteins ,0210 nano-technology ,Staphylococcus aureus ,Radical ,Supramolecular chemistry ,Microbial Sensitivity Tests ,complex mixtures ,Cellulose nanocomposite ,Protobind 1000 ,03 medical and health sciences ,Phenols ,Suspensions ,Escherichia coli ,Cellulose ,Molecular Biology ,030304 developmental biology ,technology, industry, and agriculture ,Water ,Colloid lignin particles (CLP) ,Biodegradable polymer ,[CHIM.POLY]Chemical Sciences/Polymers ,chemistry ,Chemical engineering ,Nanoparticles ,Colloid lignin particles - Abstract
openaire: EC/H2020/720303/EU//Zelcor Funding Information: This work was funded by the Bio Based Industry Joint Undertaking under the European Union's Horizon 2020 research and innovation programme within the Zelcor project (under the grant number No 720303 ), part of the COFILI project (grant number D201550245 ) for AFM measurements funded by the Grand Est Region and the European FEDER Programme and the Lignoxyl project for EPR measurements supported by the Agence Nationale de la Recherche (ANR) through the Carnot Institutes 3BCAR ( www.3bcar.fr ) and Qualiment ( https://qualiment.fr/ ) (no. 3 no. 19-CARN-001-01 and no. 16-CARN 001-01). The EPR data in this manuscript were obtained using equipment supported jointly by the French National Ministry of Research (PPF IRPE), the “Fondation pour la Recherche Médicale” (FRM DGE20061007745), and the CNRS (Department of Chemistry and Life Sciences). The IJPB benefits from the support of the LabEx Saclay Plant Sciences-SPS (ANR-10-LABX-552 0040-SPS). Funding Information: This work was funded by the Bio Based Industry Joint Undertaking under the European Union's Horizon 2020 research and innovation programme within the Zelcor project (under the grant number No 720303), part of the COFILI project (grant number D201550245) for AFM measurements funded by the Grand Est Region and the European FEDER Programme and the Lignoxyl project for EPR measurements supported by the Agence Nationale de la Recherche (ANR) through the Carnot Institutes 3BCAR (www.3bcar.fr) and Qualiment (https://qualiment.fr/) (no. 3 no. 19-CARN-001-01 and no. 16-CARN 001-01). The EPR data in this manuscript were obtained using equipment supported jointly by the French National Ministry of Research (PPF IRPE), the ?Fondation pour la Recherche M?dicale? (FRM DGE20061007745), and the CNRS (Department of Chemistry and Life Sciences). The IJPB benefits from the support of the LabEx Saclay Plant Sciences-SPS (ANR-10-LABX-552 0040-SPS). Publisher Copyright: © 2021 The Authors Copyright: Copyright2021 Elsevier B.V., All rights reserved. This study investigated the relationships between lignin molecular and supramolecular structures and their functional properties within cellulose-based solid matrix, used as a model biodegradable polymer carrier. Two types of derivatives corresponding to distinct structuration levels were prepared from a single technical lignin sample (PB1000): phenol-enriched oligomer fractions and colloidal nanoparticles (CLP). The raw lignin and its derivatives were formulated with cellulose nanocrystals or nanofibrils to prepare films by chemical oxidation or pressure-assisted filtration. The films were tested for their water and lignin retention capacities, radical scavenging capacity (RSC) and antimicrobial properties. A structural investigation was performed by infrared, electron paramagnetic resonance spectroscopy and microscopy. The composite morphology and performance were controlled by both the composition and structuration level of lignin. Phenol-enriched oligomers were the compounds most likely to interact with cellulose, leading to the smoothest film surface. Their RSC in film was 4- to 6-fold higher than that of the other samples. The organization in CLP led to the lowest RSC but showed capacity to trap and stabilize phenoxy radicals. All films were effective against S. aureus (gram negative) whatever the lignin structure. The results show the possibility to tune the performances of these composites by exploiting lignin multi-scale structure.
- Published
- 2021
41. Well-Defined Lignin Model Films from Colloidal Lignin Particles
- Author
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Muhammad Farooq, Juan José Valle-Delgado, Monika Österberg, Tao Zou, Maria Morits, and Mika Henrikki Sipponen
- Subjects
chemistry.chemical_classification ,Aqueous solution ,Nanoparticle ,02 engineering and technology ,Surfaces and Interfaces ,Polymer ,Quartz crystal microbalance ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,Adsorption ,chemistry ,Chemical engineering ,Electrochemistry ,Particle ,General Materials Science ,Particle size ,0210 nano-technology ,Dissolution ,Spectroscopy - Abstract
The transformation of a molecularly complex and irregularly shaped lignin into a nanoscale spherical architecture is anticipated to play a pivotal role in the promotion of lignin valorization. From the standpoint of using colloidal lignin particles (CLPs) as building blocks for a diverse range of applications, it has become essential to study their interactions with soluble compounds of varied origin. However, the lack of model films with well-defined surface properties similar to those of CLPs has hindered fundamental studies using surface-sensitive techniques. Here, we report well-defined and stable thin films prepared from CLPs and demonstrate their suitability for investigation of surface phenomena. Direct adsorption on substrates coated with a cationic anchoring polymer resulted in uniform distribution of CLPs as shown with atomic force microscopy (AFM). Quartz crystal microbalance with dissipation monitoring (QCM-D) experiments revealed higher adsorbed mass of cationic lignin onto the CLP-coated substrate in comparison to the film prepared from dissolved lignin, suggesting preferential adsorption via the carboxylic acid enriched surfaces of CLPs. QCM-D further enabled detection of small changes such as particle swelling or partial dissolution not detectable via bulk methods such as light scattering. The CLP thin films remained stable until pH 8 and displayed only a low degree of swelling. Increasing the pH to 10 led to some instability, but their spherical geometry remained intact until complete dissolution was observed at pH 12. Particles prepared from aqueous acetone or aqueous tetrahydrofuran solution followed similar trends regarding adsorption, pH stability, and wetting, although the particle size affected the magnitude of adsorption. Overall, our results present a practical way to prepare well-defined CLP thin films that will be useful not only for fundamental studies but also as a platform for testing stability and interactions of lignin nanoparticles with materials of technical and biomedical relevance.
- Published
- 2020
42. Bundling of cellulose microfibrils in native and polyethylene glycol-containing wood cell walls revealed by small-angle neutron scattering
- Author
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Paavo A, Penttilä, Michael, Altgen, Muhammad, Awais, Monika, Österberg, Lauri, Rautkari, and Ralf, Schweins
- Subjects
Biopolymers ,Polymers ,technology, industry, and agriculture ,Structure determination ,Characterization and analytical techniques ,Article - Abstract
Wood and other plant-based resources provide abundant, renewable raw materials for a variety of applications. Nevertheless, their utilization would greatly benefit from more efficient and accurate methods to characterize the detailed nanoscale architecture of plant cell walls. Non-invasive techniques such as neutron and X-ray scattering hold a promise for elucidating the hierarchical cell wall structure and any changes in its morphology, but their use is hindered by challenges in interpreting the experimental data. We used small-angle neutron scattering in combination with contrast variation by poly(ethylene glycol) (PEG) to identify the scattering contribution from cellulose microfibril bundles in native wood cell walls. Using this method, mean diameters for the microfibril bundles from 12 to 19 nm were determined, without the necessity of cutting, drying or freezing the cell wall. The packing distance of the individual microfibrils inside the bundles can be obtained from the same data. This finding opens up possibilities for further utilization of small-angle scattering in characterizing the plant cell wall nanostructure and its response to chemical, physical and biological modifications or even in situ treatments. Moreover, our results give new insights into the interaction between PEG and the wood nanostructure, which may be helpful for preservation of archaeological woods.
- Published
- 2020
43. Effect of laminin, polylysine and cell medium components on the attachment of human hepatocellular carcinoma cells to cellulose nanofibrils analyzed by surface plasmon resonance
- Author
-
Xue, Zhang, Tapani, Viitala, Riina, Harjumäki, Alma, Kartal-Hodzic, Juan José, Valle-Delgado, and Monika, Österberg
- Subjects
Carcinoma, Hepatocellular ,Liver Neoplasms ,Nanofibers ,Humans ,Polylysine ,Laminin ,Surface Plasmon Resonance ,Cellulose - Abstract
The development of in vitro cell models that mimic cell behavior in organs and tissues is an approach that may have remarkable impact on drug testing and tissue engineering applications in the future. Plant-based, chemically unmodified cellulose nanofibrils (CNF) hydrogel is a natural, abundant, and biocompatible material that has attracted great attention for biomedical applications, in particular for three-dimensional cell cultures. However, the mechanisms of cell-CNF interactions and factors that affect these interactions are not yet fully understood. In this work, multi-parametric surface plasmon resonance (SPR) was used to study how the adsorption of human hepatocellular carcinoma (HepG2) cells on CNF films is affected by the different proteins and components of the cell medium. Both human recombinant laminin-521 (LN-521, a natural protein of the extracellular matrix) and poly-l-lysine (PLL) adsorbed on CNF films and enhanced the attachment of HepG2 cells. Cell medium components (glucose and amino acids) and serum proteins (fetal bovine serum, FBS) also adsorbed on both bare CNF and on protein-coated CNF substrates. However, the adsorption of FBS hindered the attachment of HepG2 cells to LN-521- and PLL-coated CNF substrates, suggesting that serum proteins blocked the formation of laminin-integrin bonds and decreased favorable PLL-cell electrostatic interactions. This work sheds light on the effect of different factors on cell attachment to CNF, paving the way for the utilization and optimization of CNF-based materials for different tissue engineering applications.
- Published
- 2020
44. Non-leaching, highly biocompatible nanocellulose surfaces that efficiently resist fouling by bacteria in an artificial dermis model
- Author
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Tom Coenye, Nina Forsman, Declan C. Mullen, Per E. J. Saris, Blair F. Johnston, Susanne Stehl, Vânia M. Moreira, Leena-Sisko Johansson, Michael Chrubasik, Xing Wan, Monika Österberg, Frits van Charante, Luis M. Bimbo, Jari Yli-Kauhaluoma, Leena Keurulainen, Ralf Zimmermann, Carsten Werner, Ghada S. Hassan, Aruna S. Prakash, Division of Pharmaceutical Chemistry and Technology, Drug Research Program, Department of Microbiology, Antimicrobials, probiotics and fermented food, Pharmaceutical Design and Discovery group, Jari Yli-Kauhaluoma / Principal Investigator, University of Helsinki, Department of Bioproducts and Biosystems, University of Strathclyde, Leibniz-Institut für Polymerforschung Dresden, Ghent University, Bioproduct Chemistry, Aalto-yliopisto, and Aalto University
- Subjects
education ,116 Chemical sciences ,Biomedical Engineering ,cellulose nanofibril ,Nanotechnology ,02 engineering and technology ,010402 general chemistry ,medicine.disease_cause ,01 natural sciences ,biofilm ,RS ,Nanocellulose ,Biomaterials ,medicine ,NANOPARTICLES ,surface ,STAPHYLOCOCCUS-AUREUS ,11832 Microbiology and virology ,Fouling ,biology ,Chemistry ,DERIVATIVES ,Biochemistry (medical) ,NANOFIBRILLATED CELLULOSE ,Biofilm ,General Chemistry ,MASS-SPECTROMETRY ,ELECTROKINETICS ,021001 nanoscience & nanotechnology ,Antimicrobial ,biology.organism_classification ,0104 chemical sciences ,3. Good health ,dehydroabietic ,Leaching (chemistry) ,Staphylococcus aureus ,DISCOVERY ,ACID ,Surface modification ,FUNCTIONALIZATION ,antimicrobial ,dehydroabietic acid ,0210 nano-technology ,ANTIBIOTICS ,Bacteria - Abstract
Bacterial biofilm infections incur massive costs on healthcare systems worldwide. Particularly worrisome are the infections associated with pressure ulcers and prosthetic, plastic, and reconstructive surgeries, where staphylococci are the major biofilm-forming pathogens. Non-leaching antimicrobial surfaces offer great promise for the design of bioactive coatings to be used in medical devices. However, the vast majority are cationic, which brings about undesirable toxicity. To circumvent this issue, we have developed antimicrobial nanocellulose films by direct functionalization of the surface with dehydroabietic acid derivatives. Our conceptually unique design generates non-leaching anionic surfaces that reduce the number of viable staphylococci in suspension, including drug-resistant Staphylococcus aureus, by an impressive 4-5 log units, upon contact. Moreover, the films clearly prevent bacterial colonization of the surface in a model mimicking the physiological environment in chronic wounds. Their activity is not hampered by high protein content, and they nurture fibroblast growth at the surface without causing significant hemolysis. In this work, we have generated nanocellulose films with indisputable antimicrobial activity demonstrated using state-of-the-art models that best depict an "in vivo scenario". Our approach is to use fully renewable polymers and find suitable alternatives to silver and cationic antimicrobials.
- Published
- 2020
45. Author Correction: Quantified forces between HepG2 hepatocarcinoma and WA07 pluripotent stem cells with natural biomaterials correlate with in vitro cell behavior
- Author
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Yan-Ru Lou, Robertus Wahyu N. Nugroho, Xue Zhang, Marjo Yliperttula, Riina Harjumäki, Monika Österberg, and Juan José Valle-Delgado
- Subjects
Multidisciplinary ,medicine.anatomical_structure ,Chemistry ,lcsh:R ,Cell ,medicine ,lcsh:Medicine ,lcsh:Q ,lcsh:Science ,Induced pluripotent stem cell ,In vitro ,Cell biology - Abstract
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
- Published
- 2020
46. Three-Dimensional Printed Cell Culture Model Based on Spherical Colloidal Lignin Particles and Cellulose Nanofibril-Alginate Hydrogel
- Author
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Siqi Huan, Monika Österberg, Xue Zhang, Ari Ora, Rubina Ajdary, Muhammad Farooq, Orlando J. Rojas, Mika Henrikki Sipponen, Juan José Valle-Delgado, Markus Linder, Maria Morits, Christopher Jonkergouw, Department of Bioproducts and Biosystems, Department of Applied Physics, Biohybrid Materials, School services, CHEM, Aalto-yliopisto, and Aalto University
- Subjects
Materials science ,Polymers and Plastics ,Alginates ,Cell Culture Techniques ,Nanoparticle ,Bioengineering ,02 engineering and technology ,010402 general chemistry ,Lignin ,01 natural sciences ,Article ,Biomaterials ,Colloid ,chemistry.chemical_compound ,Materials Chemistry ,Cellulose ,Shear thinning ,Nanocomposite ,Tissue Engineering ,Tissue Scaffolds ,Hydrogels ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Shear rate ,Chemical engineering ,chemistry ,Printing, Three-Dimensional ,Self-healing hydrogels ,0210 nano-technology - Abstract
Three-dimensional (3D) printing has been an emerging technique to fabricate precise scaffolds for biomedical applications. Cellulose nanofibril (CNF) hydrogels have attracted considerable attention as a material for 3D printing because of their shear-thinning properties. Combining cellulose nanofibril hydrogels with alginate is an effective method to enable cross-linking of the printed scaffolds in the presence of Ca2+ ions. In this work, spherical colloidal lignin particles (CLPs, also known as spherical lignin nanoparticles) were used to prepare CNF-alginate-CLP nanocomposite scaffolds. High-resolution images obtained by atomic force microscopy (AFM) showed that CLPs were homogeneously mixed with the CNF hydrogel. CLPs brought antioxidant properties to the CNF-alginate-CLP scaffolds in a concentration-dependent manner and increased the viscosity of the hydrogels at a low shear rate, which correspondingly provide better shape fidelity and printing resolution to the scaffolds. Interestingly, the CLPs did not affect the viscosity at high shear rates, showing that the shear thinning behavior typical for CNF hydrogels was retained, enabling easy printing. The CNF-alginate-CLP scaffolds demonstrated shape stability after printing, cross-linking, and storage in Dulbecco's phosphate buffer solution (DPBS +) containing Ca2+ and Mg2+ ions, up to 7 days. The 3D-printed scaffolds showed relative rehydration ratio values above 80% after freeze-drying, demonstrating a high water-retaining capability. Cell viability tests using hepatocellular carcinoma cell line HepG2 showed no negative effect of CLPs on cell proliferation. Fluorescence microscopy indicated that HepG2 cells grew not only on the surfaces but also inside the porous scaffolds. Overall, our results demonstrate that nanocomposite CNF-alginate-CLP scaffolds have high potential in soft-tissue engineering and regenerative-medicine applications.
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- 2020
47. Cytokeratin 5 determines maturation of the mammary myoepithelium
- Author
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Vivi Deckwirth, Antti Sukura, Ramaswamy Krishnan, Eeva Kaisa Rajakylä, Monika Österberg, Anna Acheva, Juan José Valle-Delgado, Pia Björkenheim, Sandhanakrishnan Cattavarayane, Sari Tojkander, Niccole Schaible, University of Helsinki, Harvard Medical School, Department of Bioproducts and Biosystems, Aalto-yliopisto, Aalto University, Departments of Faculty of Veterinary Medicine, Veterinary Biosciences, Soluvälitteiset voimat syöpäsolujen invaasiossa, Veterinary Pathology and Parasitology, Equine and Small Animal Medicine, Faculty of Veterinary Medicine, Helsinki One Health (HOH), Antti Sukura / Principal Investigator, Biosciences, and Tampere University
- Subjects
EXPRESSION ,0301 basic medicine ,Science ,Biophysics ,TRANSITIONS ,02 engineering and technology ,413 Veterinary science ,Article ,PHENOTYPIC ALTERATIONS ,03 medical and health sciences ,Cytokeratin ,Stroma ,medicine ,Progenitor cell ,HUMAN BREAST ,Basement membrane ,318 Medical biotechnology ,Multidisciplinary ,PROGENITORS ,Chemistry ,IN-SITU ,Myoepithelial cell ,Cell Biology ,021001 nanoscience & nanotechnology ,CANCER ,Epithelium ,3. Good health ,Cell biology ,SELF-RENEWAL ,SNAI2 ,030104 developmental biology ,medicine.anatomical_structure ,Stem cell ,DUCTAL CARCINOMA ,0210 nano-technology ,STEM-CELLS ,Developmental Biology - Abstract
Summary At invasion, transformed mammary epithelial cells expand into the stroma through a disrupted myoepithelial (ME) cell layer and basement membrane (BM). The intact ME cell layer has thus been suggested to act as a barrier against invasion. Here, we investigate the mechanisms behind the disruption of ME cell layer. We show that the expression of basal/ME proteins CK5, CK14, and α-SMA altered along increasing grade of malignancy, and their loss affected the maintenance of organotypic 3D mammary architecture. Furthermore, our data suggests that loss of CK5 prior to invasive stage causes decreased levels of Zinc finger protein SNAI2 (SLUG), a key regulator of the mammary epithelial cell lineage determination. Consequently, a differentiation bias toward luminal epithelial cell type was detected with loss of mature, α-SMA-expressing ME cells and reduced deposition of basement membrane protein laminin-5. Therefore, our data discloses the central role of CK5 in mammary epithelial differentiation and maintenance of normal ME layer., Graphical abstract, Highlights • Cytokeratin 5 (CK5) impacts mammary epithelial cell lineage differentiation • CK5 loss at pre-invasive stage causes impaired maturation of myoepithelial cells • CK5 loss causes SLUG downregulation and differentiation bias in mammary progenitors, Cell Biology; Developmental Biology; Biophysics
- Published
- 2020
48. Eco-friendly surface hydrophobization of all-cellulose composites using layer-by-layer deposition
- Author
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Tatiana Budtova, Oona Korhonen, Monika Österberg, Nina Forsman, Centre de Mise en Forme des Matériaux (CEMEF), MINES ParisTech - École nationale supérieure des mines de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Aalto University (A?), Biorefineries, Department of Bioproducts and Biosystems, Aalto-yliopisto, and Aalto University
- Subjects
010407 polymers ,Materials science ,Polymers and Plastics ,Tensile properties ,General Chemical Engineering ,Carnauba wax ,lcsh:Chemical technology ,01 natural sciences ,chemistry.chemical_compound ,[SPI]Engineering Sciences [physics] ,carnauba wax ,Biopolymers ,lcsh:TA401-492 ,Materials Chemistry ,lcsh:TP1-1185 ,Physical and Theoretical Chemistry ,Cellulose ,Composite material ,ComputingMilieux_MISCELLANEOUS ,tensile properties ,Biocomposites ,Organic Chemistry ,Layer by layer ,Environmentally friendly ,cellulose ,0104 chemical sciences ,Hydrophobization ,[CHIM.POLY]Chemical Sciences/Polymers ,chemistry ,hydrophobisation ,lcsh:Materials of engineering and construction. Mechanics of materials ,biopolymers, biocomposites - Abstract
All-cellulose composites were prepared by dispersing kraft fibers in a matrix made from pulp dissolved in NaOH-water. To hydrophobize the composite surface while maintaining the material fully bio-based and biodegradable, layer-by-layer deposition of cationic starch and carnauba wax was performed. Various options of surface coating, drying, and curing were tested, including partial and complete melting of the wax. The composite surface was characterized by water contact angle, roughness and scanning electron microscopy, and material properties by adsorption and absorption of water (in vapor and liquid form) and tensile testing. The highest water contact angle was obtained when the layer-by-layer deposition was performed by dipping the dry composite into cationic starch solution, then in wax dispersion, and partially melting the wax after coating. However, it was demonstrated that the dipping approach was detrimental to material tensile properties, due to heterogeneous swelling of cellulose during the treatment and multiple drying sequences. Process optimization via spraying resulted in composites with Young's modulus of 6 GPa and hydrophobic surface with water contact angle 122 degrees C.
- Published
- 2020
49. Spatially confined lignin nanospheres for biocatalytic ester synthesis in aqueous media
- Author
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Muhammad Farooq, Mika Henrikki Sipponen, Monika Österberg, Jani Seitsonen, Jari Koivisto, Alessandro Pellis, Department of Bioproducts and Biosystems, Department of Chemistry and Materials Science, University of York, Department of Applied Physics, Aalto-yliopisto, and Aalto University
- Subjects
Cutinase ,Green chemistry ,Magnetic Resonance Spectroscopy ,Calcium alginate ,General Physics and Astronomy ,Biocompatible Materials ,02 engineering and technology ,Microscopy, Atomic Force ,Lignin ,01 natural sciences ,chemistry.chemical_compound ,lcsh:Science ,Candida ,Multidisciplinary ,Aqueous solution ,biology ,Chemistry ,Hydrolysis ,Esters ,Hydrogels ,021001 nanoscience & nanotechnology ,0210 nano-technology ,Nanospheres ,Alginates ,Science ,010402 general chemistry ,Catalysis ,Article ,General Biochemistry, Genetics and Molecular Biology ,Fungal Proteins ,Microscopy, Electron, Transmission ,Colloids ,Lipase ,Water ,General Chemistry ,Enzymes, Immobilized ,biology.organism_classification ,equipment and supplies ,Nanostructures ,0104 chemical sciences ,Chemical engineering ,Biocatalysis ,biology.protein ,lcsh:Q ,Candida antarctica ,Adsorption - Abstract
Dehydration reactions proceed readily in water-filled biological cells. Development of biocatalysts that mimic such compartmentalized reactions has been cumbersome due to the lack of low-cost nanomaterials and associated technologies. Here we show that cationic lignin nanospheres function as activating anchors for hydrolases, and enable aqueous ester synthesis by forming spatially confined biocatalysts upon self-assembly and drying-driven aggregation in calcium alginate hydrogel. Spatially confined microbial cutinase and lipase retain 97% and 70% of their respective synthetic activities when the volume ratio of water to hexane increases from 1:1 to 9:1 in the reaction medium. The activity retention of industrially most frequently used acrylic resin-immobilized Candida antarctica lipase B is only 51% under similar test conditions. Overall, our findings enable fabrication of robust renewable biocatalysts for aqueous ester synthesis, and provide insight into the compartmentalization of diverse heterogeneous catalysts., Development of biocatalysts that mimic compartmentalized reactions in cells has been cumbersome due to the lack of low-cost materials and associated technologies. Here the authors show that cationic lignin nanospheres function as activating anchors for hydrolases, and enable aqueous ester synthesis by forming spatially confined biocatalysts.
- Published
- 2018
50. Aggregation response of triglyceride hydrolysis products in cyclohexane and triolein
- Author
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Maria Sammalkorpi, Monika Österberg, Sampsa Vierros, Department of Chemistry and Materials Science, Bioproduct Chemistry, Department of Bioproducts and Biosystems, Aalto-yliopisto, and Aalto University
- Subjects
010304 chemical physics ,Cyclohexane ,Hydrogen bond ,General Physics and Astronomy ,02 engineering and technology ,Monoglyceride ,021001 nanoscience & nanotechnology ,01 natural sciences ,Micelle ,Hydrolysis ,chemistry.chemical_compound ,Molecular dynamics ,chemistry ,Pulmonary surfactant ,Chemical engineering ,0103 physical sciences ,Triolein ,Physical and Theoretical Chemistry ,0210 nano-technology ,ta116 - Abstract
Here, we examine the aggregation response of a series of triglyceride-based biosurfactants in cyclohexane and triglyceride solvents via all-atom molecular dynamics simulations and supporting experiments. The surfactant aggregation follows in all systems, with only minor deviations, a multiple equilibrium, i.e. open association, model. Monoglyceride aggregation in cyclohexane exhibits a critical micellization concentration, cmc, showing a cmc can exist even in a system following open association. However, the cmc is associated with a change in balance with oligomeric and larger aggregates in the solution, not an onset of aggregate formation. It is demonstrated that reverse micelles can form in the absence of water stabilized by intersurfactant hydrogen bonds alone, and that the polarity and hydrogen bonding capability of triolein systematically reduces surfactant aggregation in comparison to cyclohexane. A comparison between CHARMM27 and CHARMM36 simulation models reveals that while trends are preserved, the models differ in quantitative prediction. Finally, consolidation of the general aggregation response trends predicted by the modelling are obtained via 7,7,8,8-tetracyanoquinodimethane dye (TCNQ) solubilization experiments on the corresponding model plant oil systems. The findings provide guidelines for predicting and controlling surfactant aggregation response in organic solvents via tuning the solvent polarity and hydrogen bonding ability, and a critical assessment of simulation and aggregation models for surfactant systems in organic solvents.
- Published
- 2018
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