23 results on '"Lanti Yang"'
Search Results
2. Unprecedented Adhesive Performance of Propylene-Based Hydroxyl-Functionalized Terpolymers
- Author
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Jakub Kruszynski, Weronika Nowicka, Miloud Bouyahyi, Yingxin Liu, Lanti Yang, Artur Rozanski, Nithish Anbuchezhian, Lidia Jasinska-Walc, and Rob Duchateau
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Polymers and Plastics ,Process Chemistry and Technology ,Organic Chemistry - Published
- 2023
3. Self-Organization of Graft Copolymers and Retortable iPP-Based Nanoporous Films Thereof
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Thomas Defize, Miloud Bouyahyi, Artur Rozanski, Lanti Yang, Bhaskar Patham, Teun Sweere, Sebastian Hochstädt, Michael Ryan Hansen, Katrien V. Bernaerts, Lidia Jasinska-Walc, Rob Duchateau, Product Technology, RS: FSE AMIBM, and AMIBM
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MECHANISM ,POLYETHYLENE ,Polymers and Plastics ,nanoporous films ,ELECTROLYTES ,Process Chemistry and Technology ,Organic Chemistry ,FUNCTIONAL SILYL GROUPS ,RESOLUTION C-13 NMR ,POLY(ETHER IMIDE) ,self-assembling ,POROUS MEMBRANES ,POLYMERIZATION ,THIN-FILMS ,BLOCK-COPOLYMER ,graft copolymers ,morphology ,polypropylene - Abstract
Polyolefins might become inexpensive alternatives to the existing membranes based on polyethersulfone. Here, we disclose the production of retortable, well-defined polypropylene (PP)-based nanoporous films derived from amphiphilic graft copolymer precursors. The graft copolymers, containing a polypropylene backbone and polyester grafts, were obtained by grafting lactones, specifically delta-valerolactone and epsilon- caprolactone, from well-defined randomly functionalized poly(propylene-co-10-undecen-1-ol) as a macroinitiator. Depending on the composition, the graft copolymers self-assemble into droplet, cylindrical, lamellar, or interconnected two-phase morphologies. Functional mesoporous iPP-based films were fabricated by the selective degradation of the polyester blocks of the copolymers. Their structure and morphology were studied using atomic force microscopy (AFM), scanning electron microscopy (SEM), small-angle X-ray scattering (SAXS), and solid-state NMR, while the mesoporosity was assessed by nitrogen sorption experiments. The pore size of the films is strongly influenced not only by the volume fraction of the copolymer blocks but unexpectedly also by the topology (i.e., number of grafts) of the graft copolymer, as was confirmed by computational modeling studies using the dynamic density functional theory (DDFT) engine within the Culgi software. This work provides a conclusive answer on how the morphology of iPP-based graft copolymers is tuned by the copolymer composition and the amount and length of the grafted polyester blocks. Filtration tests and flux determination demonstrated that such structurally well-defined mesoporous products could be considered for the development of ultrafiltration membranes while the chemical resistance and sterilization tests revealed their robust performance and suitability for water purification applications.
- Published
- 2022
4. Ink-Deposited Transparent Electrochromic Structural Colored Foils
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Arne A. F. Froyen, Nadia Grossiord, Jos de Heer, Toob Meerman, Lanti Yang, Johan Lub, Albert P. H. J. Schenning, and Stimuli-responsive Funct. Materials & Dev.
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cholesteric liquid crystal ,silver nanowire ,photonic coating ,General Materials Science ,structural color ,transparent heater ,electrochromic - Abstract
Despite progress in the field of electrochromic devices, developing structural color-tunable photonic systems having both high transparency and flexibility remains challenging. Here, an ink-deposited transparent electrochromic structural colored foil displaying reflective colors, tuned by an integrated heater, is prepared in a single-substrate method. Efficient and homogeneous heating is induced by a gravure printed silver nanowire-based substrate, delivering an electrothermal response upon applying an electrical potential. On top of this flexible, transparent heater, a cholesteric liquid crystal ink is bar-coated and subsequently photopolymerized, yielding a structural colored film that exhibits temperature-responsive color changes. The transparent electrochromic foils appear colorless at room temperature but demonstrate structural color tuning with high optical quality when modifying the electrical potential. Both optical and electrothermal performances were preserved when deforming the foils. Applying the conductive and structural colored inks via the easy processable, continuous methods of gravure printing and bar-coating highlights the potential for scaling up to large-scale stimuli-responsive, transparent optical foils. These transparent structural colored foils can be potentially used for a wide range of photonic devices including smart windows, displays, and sensors and can be directly installed on top of curved, flexible surfaces.
- Published
- 2022
5. Structurally well-defined functionalized polyolefins and graft copolymers thereof as bitumen modifiers
- Author
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Mateusz Malus, Joanna Bojda, Maciej Sienkiewicz, Miloud Bouyahyi, Lanti Yang, Francisco Javier Navarro, Maria Soliman, Rob Duchateau, and Lidia Jasinska-Walc
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General Materials Science ,Building and Construction ,Civil and Structural Engineering - Published
- 2023
6. Silicon Oxide Barrier Films Deposited on Polycarbonate Substrates in Pulsed Plasmas
- Author
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Marcel Rudolph, Lanti Yang, Shaham Shafaei, and Peter Awakowicz
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010302 applied physics ,Hexamethyldisiloxane ,Materials science ,Silicon ,General Chemical Engineering ,chemistry.chemical_element ,General Chemistry ,Surface finish ,Substrate (electronics) ,engineering.material ,Condensed Matter Physics ,01 natural sciences ,010305 fluids & plasmas ,Surfaces, Coatings and Films ,chemistry.chemical_compound ,Coating ,chemistry ,Plasma-enhanced chemical vapor deposition ,0103 physical sciences ,engineering ,Thin film ,Composite material ,Silicon oxide - Abstract
For many applications of polycarbonate (PC) from packaging to micro-electronics improved barrier properties are necessary. In this contribution, silica thin films were deposited from hexamethyldisiloxane/oxygen (HMDSO/O2) on polycarbonate substrate in three step plasma processes by combining a microwave (MW) surface wave discharge of 2.45 GHz with an optional radio-frequency (RF) bias of 13.56 MHz. The influence of interlayer thickness, HMDSO flow and oxygen to HMDSO ratio on barrier performance for three step-coating processes was investigated. The morphology and surface properties of the coated surface of PC were studied by atomic force microscopy (AFM). The surface topography showed a silica particles distribution on the PC substrate with relatively smooth surface roughness. AFM-QNM provides more insight into the surface morphology and stiffness. The results identify the coating structure for PC film coated with and without bias. High barrier improvement of the deposited films on PC substrates was obtained after plasma silicon coating process with a barrier improvement factor up to 337. It was found that the deposition process is optimal for food packaging applications by using combined MW-RF PECVD technology.
- Published
- 2019
7. Anisotropic iridescence and polarization patterns in a direct ink written chiral photonic polymer
- Author
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Lanti Yang, Michael G. Debije, Nadia Grossiord, Henk Sentjens, Jeroen A. H. P. Sol, Albertus P. H. J. Schenning, Stimuli-responsive Funct. Materials & Dev., Institute for Complex Molecular Systems, ICMS Core, and EIRES Chem. for Sustainable Energy Systems
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chemistry.chemical_classification ,Materials science ,tunable dichroism ,Inkwell ,photonic inks ,business.industry ,Mechanical Engineering ,Polymer ,Polarization (waves) ,Elastomer ,photonic structures ,Iridescence ,chiral nematic liquid crystals ,chemistry ,chiroptical materials ,Mechanics of Materials ,Optoelectronics ,General Materials Science ,Photonics ,Anisotropy ,business ,direct ink writing ,Structural coloration - Abstract
The iridescence of structural color and its polarization characteristics originate from the nanoscale organization of materials. A major challenge in materials science is generating the bright, lustrous hues seen in nature through nanoscale engineering, while simultaneously controlling interaction of the material with different light polarizations. In this work, a suitable chiral nematic liquid crystal elastomer ink is synthesized for direct ink writing, which self-assembles into a chiral photonic structure. Tuning the writing direction and speed leads to the programmed formation of a slanted photonic axis, which exhibits atypical iridescence and polarization selectivity. After crosslinking, a freely programmable, chiroptical photonic polymer material is obtained. The strongly perspective-dependent appearance of the material can function as specialized anticounterfeit markers, as optical elements in decorative iridescent coatings, or, as demonstrated here, in optically based signaling features.
- Published
- 2021
8. Characterizations of Responsive Photonic Liquid Crystal Network Coatings on Flexible Plastic Substrates by Atomic Force Microscopy
- Author
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Lanti Yang
- Subjects
Materials science ,business.industry ,Liquid crystal ,Atomic force microscopy ,Optoelectronics ,Photonics ,business - Published
- 2021
9. The re-usability of heat-exposed poly (ethylene terephthalate) powder for laser sintering
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Zahir Bashir, Hao Gu, and Lanti Yang
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0209 industrial biotechnology ,Materials science ,Ethylene ,Manufacturing process ,Biomedical Engineering ,Re usability ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Industrial and Manufacturing Engineering ,law.invention ,Selective laser sintering ,chemistry.chemical_compound ,020901 industrial engineering & automation ,Chemical engineering ,chemistry ,law ,Polyamide ,Degradation (geology) ,General Materials Science ,0210 nano-technology ,Engineering (miscellaneous) ,Poly ethylene - Abstract
Selective laser sintering, also called laser sintering (LS), is an additive manufacturing process that requires micronized plastic powder. Recently, we showed poly (ethylene terephthalate (PET) powder is a suitable material for LS, with a comparable printing performance as the current front-runner, polyamide 12 (PA12). However, the LS process, by its nature, leaves unused powder that has been exposed to heat for prolonged time, and this powder may not be fully re-usable due to degradation. In this work, the re-use potential of heat-exposed PET powder is established. This is a matter of crucial importance as powders suitable for LS are very expensive, and the powder left after a building episode has to be re-used. Heat-exposed PA12 has to be blended or refreshed with virgin powder, to avoid printing defects. In contrast, heat-exposed PET powder, after 96 h at 210 °C, could be used, without refreshing with a portion of virgin powder. The printed articles from heat-exposed powders were as good as those from the fresh powder. There was no cross-linking and there was only a minor increase in the molecular weight of the powder after 96 h, at 210 °C.
- Published
- 2019
10. Powder bed fusion of aluminum –poly(ethylene terephthalate) hybrid powder: Process behavior and characterization of printed parts
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Hao Gu, Fayez AlFayez, Lanti Yang, Toseef Ahmed, and Zahir Bashir
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Biomedical Engineering ,General Materials Science ,Engineering (miscellaneous) ,Industrial and Manufacturing Engineering - Published
- 2022
11. Tunable photonic materials via monitoring step-growth polymerization kinetics by structural colors
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Ellen P. A. van Heeswijk, Albertus P. H. J. Schenning, Lanti Yang, Nadia Grossiord, Stimuli-responsive Funct. Materials & Dev., Institute for Complex Molecular Systems, ICMS Core, and EIRES Chem. for Sustainable Energy Systems
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Materials science ,photonics ,02 engineering and technology ,engineering.material ,010402 general chemistry ,Elastomer ,01 natural sciences ,Photonic metamaterial ,Biomaterials ,liquid crystals ,Coating ,Liquid crystal ,Michael addition ,Electrochemistry ,in situ characterization ,stimuli-responsive coatings ,chemistry.chemical_classification ,Polymer ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,0104 chemical sciences ,Electronic, Optical and Magnetic Materials ,Step-growth polymerization ,Photopolymer ,chemistry ,Chemical engineering ,Polymerization ,engineering ,0210 nano-technology - Abstract
The functional and responsive properties of elastomeric materials highly depend on crosslink density and molecular weight between crosslinks. However, tedious analytical steps are needed to obtain polymer network structure–property relationships. In this article, an in situ structure–property characterization method is reported by monitoring the structural color change in a photonic elastomeric material. The photonic materials are prepared in a two-step polymerization process. First, linear chain extension occurs via Michael addition. Second, photopolymerization ensures crosslinking, resulting in the formation of an elastomeric photonic network. During the first step, the step-growth polymer process can be monitored by following the photonic reflection band redshift, allowing to program the molecular weight between the crosslinks. During network formation, the crosslink density, chain length between crosslinks, and the colors are “frozen in.” These processes can be locally controlled creating both single-layered multicolor patterned and broadband reflective coatings at room temperature. The scalability of the coating process is further demonstrated by using a gravure printing technique. Additionally, the final coatings are made responsive toward specific solvents and temperature. Here the modulus, response, and color of the coating are controlled by tuning the crosslink density and molecular weight between crosslinks of the elastomeric material.
- Published
- 2020
12. Evaluation of poly(ethylene terephthalate) powder as a material for selective laser sintering, and characterization of printed part
- Author
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Zahir Bashir, Hao Gu, and Lanti Yang
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Materials science ,Polymers and Plastics ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,law.invention ,Characterization (materials science) ,Selective laser sintering ,Chemical engineering ,law ,Materials Chemistry ,0210 nano-technology ,Poly ethylene - Published
- 2017
13. Strong and Reversible Monovalent Supramolecular Protein Immobilization
- Author
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Lanti Yang, Hoang Duc Nguyen, Jurriaan Huskens, Luc Brunsveld, Pascal Jonkheijm, Jacqui F. Young, Chemical Biology, Molecular Nanofabrication, and Faculty of Science and Technology
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Macrocyclic Compounds ,Metallocenes ,Inorganic chemistry ,Supramolecular chemistry ,Biochemistry ,Supramolecular Chemistry ,chemistry.chemical_compound ,protein ligation ,Bacterial Proteins ,IR-72762 ,Cucurbituril ,Spectroscopy, Fourier Transform Infrared ,Monolayer ,Molecule ,Ferrous Compounds ,protein immobilization ,Surface plasmon resonance ,Molecular Biology ,Ligand ,host–guest systems ,Organic Chemistry ,food and beverages ,Surface Plasmon Resonance ,Combinatorial chemistry ,Fluorescence ,Luminescent Proteins ,Immobilized Proteins ,Microscopy, Fluorescence ,Ferrocene ,chemistry ,METIS-274009 ,Molecular Medicine - Abstract
Proteins with an iron clasp: Site-selective incorporation of a ferrocene molecule into a protein allows for easy, strong, and reversible supramolecular protein immobilization through a selective monovalent interaction of the ferrocene with a cucurbit[7]uril immobilized on a gold surface. The proteins can be printed in a uniform monolayer that is resistant to washing conditions, but can be removed through competition with an excess of ferrocene ligand.
- Published
- 2009
14. Microscale mechanical properties of single elastic fibers: the role of fibrillin-microfibrils
- Author
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Willeke F. Daamen, Dieter P. Reinhardt, Martin L. Bennink, Jan Feijen, Mieke M J F Koenders, Toin H. van Kuppevelt, Lanti Yang, Pieter J. Dijkstra, Ronnie G. Wismans, Kees van der Werf, Faculty of Science and Technology, Biomaterials Science and Technology, and Nanobiophysics
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musculoskeletal diseases ,Materials science ,Cantilever ,Nano-indentation ,Biophysics ,Mechanical properties ,Bioengineering ,Nanotechnology ,Bending ,macromolecular substances ,METIS-262783 ,Fibrillins ,Microscopy, Atomic Force ,Biomaterials ,Fibrillin Microfibrils ,Indentation ,medicine.ligament ,medicine ,Composite material ,AFM (atomic force microscopy) ,Microscale chemistry ,Microfilament Proteins ,technology, industry, and agriculture ,Nanoindentation ,Tissue engineering and pathology [NCMLS 3] ,Elastic Tissue ,Elastin ,Mechanics of Materials ,Microfibrils ,Microscopy, Electron, Scanning ,Ceramics and Composites ,Ligamentum nuchae ,Mechanical test ,Stress, Mechanical ,IR-60757 ,Displacement (fluid) - Abstract
Contains fulltext : 79597.pdf (Publisher’s version ) (Closed access) Micromechanical properties of single elastic fibers and fibrillin-microfibrils, isolated from equine ligamentum nuchae using chemical and enzymatic methods, were determined with atomic force microscopy (AFM). Young's moduli of single elastic fibers immersed in water, devoid of or containing fibrillin-microfibrils, were determined using bending tests. Bending freely suspended elastic fibers on a micro-channeled substrate by a tip-less AFM cantilever generated a force versus displacement curve from which Young's moduli were calculated. For single elastic fibers, Young's moduli in the range of 0.3-1.5 MPa were determined, values not significantly affected by the presence of fibrillin-microfibrils. To further understand the role of fibrillin-microfibrils in vertebrate elastic fibers, layers of fibrillin-microfibrils were subjected to nano-indentation tests. From the slope of the force versus indentation curves, Young's moduli ranging between 0.56 and 0.74 MPa were calculated. The results suggest that fibrillin-microfibrils are not essential for the mechanical properties of single vertebrate elastic fibers.
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- 2009
15. Micromechanical bending of single collagen fibrils using atomic force microscopy
- Author
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Bart F.J.M. Koopman, Pieter J. Dijkstra, Vinod Subramaniam, Lanti Yang, Martin L. Bennink, Jan Feijen, Kees van der Werf, Executive board Vrije Universiteit, Faculty of Engineering Technology, Faculty of Science and Technology, Biomaterials Science and Technology, and Nanobiophysics
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Materials science ,Biomedical Engineering ,Modulus ,Biocompatible Materials ,Young's modulus ,macromolecular substances ,Bending ,In Vitro Techniques ,Research Support ,Microscopy, Atomic Force ,Fibril ,Electron ,IR-71104 ,Collagen Type I ,Biomaterials ,symbols.namesake ,chemistry.chemical_compound ,Materials Testing ,Microscopy ,Journal Article ,Animals ,Scanning ,Dimethylpolysiloxanes ,Composite material ,Non-U.S. Gov't ,Research Support, Non-U.S. Gov't ,Linear elasticity ,Isotropy ,Metals and Alloys ,Atomic Force ,Biomechanical Phenomena ,chemistry ,Microscopy, Electron, Scanning ,Ceramics and Composites ,symbols ,METIS-244617 ,Cattle ,Glutaraldehyde - Abstract
A new micromechanical technique was developed to study the mechanical properties of single collagen fibrils. Single collagen fibrils, the basic components of the collagen fiber, have a characteristic highly organized structure. Fibrils were isolated from collagenous materials and their mechanical properties were studied with atomic force microscopy (AFM). In this study, we determined the Young's modulus of single collagen fibrils at ambient conditions from bending tests after depositing the fibrils on a poly(dimethyl siloxane) (PDMS) substrate containing micro-channels. Force-indentation relationships of freely suspended collagen fibrils were determined by loading them with a tip-less cantilever. From the deflection-piezo displacement curve, force-indentation curves could be deduced. With the assumption that the behavior of collagen fibrils can be described by the linear elastic theory of isotropic materials and that the fibrils are freely supported at the rims, a Young's modulus of 5.4 +/- 1.2 GPa was determined. After cross-linking with glutaraldehyde, the Young's modulus of a single fibril increases to 14.7 +/- 2.7 GPa. When it is assumed that the fibril would be fixed at the ends of the channel the Young's moduli of native and cross-linked collagen fibrils are calculated to be 1.4 +/- 0.3 GPa and 3.8 +/- 0.8 GPa, respectively. The minimum and maximum values determined for native and glutaraldehyde cross-linked collagen fibrils represent the boundaries of the Young's modulus.
- Published
- 2007
16. Supramolecularly oriented immobilization of proteins using cucurbit[8]uril
- Author
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Alberto Gomez-Casado, Jurriaan Huskens, Luc Brunsveld, Lanti Yang, M. Brasch, Pascal Jonkheijm, DA Dana Uhlenheuer, Arántzazu González-Campo, Molecular Nanofabrication, Biomolecular Nanotechnology, Faculty of Science and Technology, and Chemical Biology
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Yellow fluorescent protein ,Bridged-Ring Compounds ,Models, Molecular ,Protein Conformation ,Surface Properties ,Supramolecular chemistry ,IR-85054 ,Naphthols ,010402 general chemistry ,Photochemistry ,METIS-293809 ,01 natural sciences ,Polymer chemistry ,Electrochemistry ,medicine ,Moiety ,Molecule ,General Materials Science ,Surface plasmon resonance ,Spectroscopy ,Binding Sites ,biology ,010405 organic chemistry ,Chemistry ,Imidazoles ,Viologen ,Surfaces and Interfaces ,Condensed Matter Physics ,Fluorescence ,0104 chemical sciences ,Quaternary Ammonium Compounds ,Luminescent Proteins ,Immobilized Proteins ,Microcontact printing ,biology.protein ,medicine.drug - Abstract
A supramolecular strategy is used for oriented positioning of proteins on surfaces. A viologen-based guest molecule is attached to the surface, while a naphthol guest moiety is chemoselectively ligated to a yellow fluorescent protein. Cucurbit[8]uril (CB[8]) is used to link the proteins onto surfaces through specific charge-transfer interactions between naphthol and viologen inside the CB cavity. The assembly process is characterized using fluorescence and atomic force microscopy, surface plasmon resonance, IR-reflective absorption, and X-ray photoelectron spectroscopy measurements. Two different immobilization routes are followed to form patterns of the protein ternary complexes on the surfaces. Each immobilization route consists of three steps: (i) attaching the viologen to the glass using microcontact chemistry, (ii) blocking, and (iii) either incubation or microcontact printing of CB[8] and naphthol guests. In both cases uniform and stable fluorescent patterns are fabricated with a high signal-to-noise ratio. Control experiments confirm that CB[8] serves as a selective linking unit to form stable and homogeneous ternary surface-bound complexes as envisioned. The attachment of the yellow fluorescent protein complexes is shown to be reversible and reusable for assembly as studied using fluorescence microscopy.
- Published
- 2012
17. Reversible and oriented immobilization of ferrocene-modified proteins
- Author
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Jordi Cabanas-Danés, Alberto Gomez-Casado, Lanti Yang, Pascal Jonkheijm, Jacqui F. Young, Jurriaan Huskens, Hoang Duc Nguyen, Luc Brunsveld, Chemical Biology, Molecular Nanofabrication, Physics of Complex Fluids, and Faculty of Science and Technology
- Subjects
Metallocenes ,Supramolecular chemistry ,Analytical chemistry ,IR-85057 ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Catalysis ,Divalent ,chemistry.chemical_compound ,Colloid and Surface Chemistry ,Ferrous Compounds ,Surface plasmon resonance ,chemistry.chemical_classification ,010405 organic chemistry ,Proteins ,METIS-293815 ,General Chemistry ,Surface Plasmon Resonance ,Binding constant ,Fluorescence ,Combinatorial chemistry ,0104 chemical sciences ,Microscopy, Fluorescence ,Ferrocene ,chemistry ,Covalent bond ,Micropatterning - Abstract
Adopting supramolecular chemistry for immobilization of proteins is an attractive strategy that entails reversibility and responsiveness to stimuli. The reversible and oriented immobilization and micropatterning of ferrocene-tagged yellow fluorescent proteins (Fc-YFPs) onto β-cyclodextrin (βCD) molecular printboards was characterized using surface plasmon resonance (SPR) spectroscopy and fluorescence microscopy in combination with electrochemistry. The proteins were assembled on the surface through the specific supramolecular host-guest interaction between βCD and ferrocene. Application of a dynamic covalent disulfide lock between two YFP proteins resulted in a switch from monovalent to divalent ferrocene interactions with the βCD surface, yielding a more stable protein immobilization. The SPR titration data for the protein immobilization were fitted to a 1:1 Langmuir-type model, yielding K(LM) = 2.5 × 10(5) M(-1) and K(i,s) = 1.2 × 10(3) M(-1), which compares favorably to the intrinsic binding constant presented in the literature for the monovalent interaction of ferrocene with βCD self-assembled monolayers. In addition, the SPR binding experiments were qualitatively simulated, confirming the binding of Fc-YFP in both divalent and monovalent fashion to the βCD monolayers. The Fc-YFPs could be patterned on βCD surfaces in uniform monolayers, as revealed using fluorescence microscopy and atomic force microscopy measurements. Both fluorescence microscopy imaging and SPR measurements were carried out with the in situ capability to perform cyclic voltammetry and chronoamperometry. These studies emphasize the repetitive desorption and adsorption of the ferrocene-tagged proteins from the βCD surface upon electrochemical oxidation and reduction, respectively.
- Published
- 2012
- Full Text
- View/download PDF
18. Micromechanical analysis of native and cross-linked collagen type I fibrils supports the existence of microfibrils
- Author
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Pieter J. Dijkstra, K.O. van der Werf, Martin L. Bennink, Lanti Yang, and Jan Feijen
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Models, Molecular ,Materials science ,Surface Properties ,Biomedical Engineering ,macromolecular substances ,Buffers ,Fibril ,Microscopy, Atomic Force ,Viscoelasticity ,Collagen Type I ,Biomaterials ,Stress (mechanics) ,Tensile Strength ,Ultimate tensile strength ,Stress relaxation ,Animals ,Composite material ,Mechanical Phenomena ,Strain (chemistry) ,Viscosity ,Microstructure ,Elasticity ,Hysteresis ,Cross-Linking Reagents ,Mechanics of Materials ,Cattle ,Glass ,Stress, Mechanical - Abstract
The mechanical properties of individual collagen fibrils of approximately 200 nm in diameter were determined using a slightly adapted AFM system. Single collagen fibrils immersed in PBS buffer were attached between an AFM cantilever and a glass surface to perform tensile tests at different strain rates and stress relaxation measurements. The stress-strain behavior of collagen fibrils immersed in PBS buffer comprises a toe region up to a stress of 5 MPa, followed by the heel and linear region at higher stresses. Hysteresis and strain-rate dependent stress-strain behavior of collagen fibrils were observed, which suggest that single collagen fibrils have viscoelastic properties. The stress relaxation process of individual collagen fibrils could be best fitted using a two-term Prony series. Furthermore, the influence of different cross-linking agents on the mechanical properties of single collagen fibrils was investigated. Based on these results, we propose that sliding of microfibrils with respect to each other plays a role in the viscoelastic behavior of collagen fibrils in addition to the sliding of collagen molecules with respect to each other. Our finding provides a better insight into the relationship between the structure and mechanical properties of collagen and the micro-mechanical behavior of tissues.
- Published
- 2011
19. Quantitative Morphology Characterization of New PC-siloxane Copolymer Blends
- Author
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Ramon Groote, Lanti Yang, Robert Dirk Van De Grampel, and O Guise
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chemistry.chemical_compound ,Materials science ,chemistry ,Chemical engineering ,Siloxane ,Quantitative morphology ,Copolymer ,Instrumentation ,Characterization (materials science) - Published
- 2014
20. Mechanical properties of native and cross-linked type I collagen fibrils
- Author
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Kees van der Werf, Martin L. Bennink, Carel F.C. Fitié, Pieter J. Dijkstra, Lanti Yang, Jan Feijen, Molecular Nanofabrication, Faculty of Science and Technology, Biomaterials Science and Technology, and Nanobiophysics
- Subjects
Materials science ,Fibrillar Collagens ,Biophysics ,Modulus ,Bending ,macromolecular substances ,Microscopy, Atomic Force ,Fibril ,Collagen Type I ,Stress (mechanics) ,Shear modulus ,stomatognathic system ,Pressure ,Animals ,Composite material ,Anisotropy ,Models, Statistical ,Flexural modulus ,Temperature ,Proteins ,Equipment Design ,Extracellular Matrix ,Cross-Linking Reagents ,Cattle ,Collagen ,Stress, Mechanical ,Type I collagen - Abstract
Micromechanical bending experiments using atomic force microscopy were performed to study the mechanical properties of native and carbodiimide-cross-linked single collagen fibrils. Fibrils obtained from a suspension of insoluble collagen type I isolated from bovine Achilles tendon were deposited on a glass substrate containing microchannels. Force-displacement curves recorded at multiple positions along the collagen fibril were used to assess the bending modulus. By fitting the slope of the force-displacement curves recorded at ambient conditions to a model describing the bending of a rod, bending moduli ranging from 1.0 GPa to 3.9 GPa were determined. From a model for anisotropic materials, the shear modulus of the fibril is calculated to be 33 +/- 2 MPa at ambient conditions. When fibrils are immersed in phosphate-buffered saline, their bending and shear modulus decrease to 0.07-0.17 GPa and 2.9 +/- 0.3 MPa, respectively. The two orders of magnitude lower shear modulus compared with the Young's modulus confirms the mechanical anisotropy of the collagen single fibrils. Cross-linking the collagen fibrils with a water-soluble carbodiimide did not significantly affect the bending modulus. The shear modulus of these fibrils, however, changed to 74 +/- 7 MPa at ambient conditions and to 3.4 +/- 0.2 MPa in phosphate-buffered saline.
- Published
- 2008
21. iPP/HDPE blends compatibilized by a polyester: An unconventional concept to valuable products.
- Author
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Kruszynski, Jakub, Nowicka, Weronika, Rozanski, Artur, Yingxin Liu, Parisi, Daniele, Lanti Yang, Pasha, Farhan Ahmad, Bouyahyi, Miloud, Jasinska-Walc, Lidia, and Duchateau, Rob
- Subjects
- *
HIGH density polyethylene , *POLYESTERS , *COMPATIBILIZERS , *POLYPROPYLENE , *CHEMICAL structure - Abstract
Polyolefins are the most widely used plastics accounting for a large fraction of the polymer waste stream. Although reusing polyolefins seems to be a logical choice, their recycling level remains disappointingly low. This is mainly due to the lack of large-scale availability of efficient and inexpensive compatibilizers for mixed polyolefin waste, typically consisting of high-density polyethylene (HDPE) and isotactic polypropylene (iPP) that, despite their similar chemical hydrocarbon structure, are immiscible. Here, we describe an unconventional approach of using polypentadecalactone, a straightforward and simple-to-produce aliphatic polyester, as a compatibilizer for iPP/HDPE blends, especially the brittle iPP-rich ones. The unexpectedly effective compatibilizer transforms brittle iPP/HDPE blends into unexpectedly tough materials that even outperform the reference HDPE and iPP materials. This simple approach creates opportunities for upcycling polymer waste into valuable products. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
22. Supramolecular Protein Immobilization Strategies
- Author
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Dorothee Wasserberg, An, Q., Cabanes-Danes, J., Stoffelen, C., Lanti Yang, Gonzalez Campo, A., Brasch, M., Vinod Subramaniam, Jurriaan Huskens, Pascal Jonkheijm, Molecular Nanofabrication, Nanobiophysics, and Biomolecular Nanotechnology
- Subjects
METIS-271306
23. Micromechanical bending of single collagen fibril using AFM
- Author
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Lanti Yang, Kees van der Werf, Martin Bennink, Pieter Dijkstra, Bart Koopman, Jan Feijen, and Vinod Subramaniam
Catalog
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