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The utilization of biopolymer hydrogels has been challenging due to the lack of controllability, actuation, and quick-response properties. Herein, we report a strategic nanoparticle-free approach toward magnetoresponsive biocomposite hydrogels by combining a biopolymer (gelatin) and vesicles of essential amino acid (valine)-based magnetic ionic liquid surfactant [ValC16][FeCl4], and explored their potency as drug delivery nanocarriers. Self-assembly characteristics of [ValC16][FeCl4] have been investigated using surface tension, pyrene fluorescence, specific conductivity, DLS, and TEM measurements. The biocompatible nature of [ValC16][FeCl4] was confirmed by investigating its physiochemical interaction with animal DNA using circular dichroism, zeta potential, agarose gel electrophoresis, and ethidium bromide exclusion assay test. The gel strength and magnetic behavior of the prepared biocomposite magnetoresponsive hydrogels were measured using rheology and vibrating sample magnetometry techniques, respectively. The constructed biocomposite hydrogel has been employed as drug delivery carriers for an antibiotic drug (ornidazole) and an anticancer drug (5-fluorouracil). The encapsulation efficiency of ornidazole and 5-fluorouracil in the magnetic biocomposite gel was found to be 69 ± 0.6% and 78 ± 0.3%, respectively. Since magnetoresponsive biomaterials can be manipulated spatiotemporally via an external magnetic field, the prepared nanoparticle-free magnetoresponsive hydrogels can be promising candidates as active scaffolds for advanced drug delivery and tissue regeneration applications.

The lack of the required mechanical strength and adequate biodegradation rate of calcium phosphate materials constitutes the most relevant drawback prohibiting their use for orthopaedic applications. One of the promising strategies to overcome this intrinsic limitation is the functionalization of these materials through the combination with specific functional groups. In this study, we investigated APTES (3-aminopropyl-triethoxy-silane) functionalization of a poorly crystalline apatite (PCA) and its further combination for the first time to chitosan (CS) to elaborate PCA-APTES-CS functionalized composite material. XRD patterns of the elaborated materials exhibit broad peaks typical of poorly crystalline apatite. FTIR spectroscopy showed, in addition to the PCA characteristic bands, bands assigned to silane alkyl groups and evidenced the success of functionalization process. The TGA analysis confirmed the attachment of 8 wt% of APTES and 3 wt% of chitosan within the composite. SEM microscopy and EDX silicon mapping demonstrated a homogeneous silane presence on functionalized apatite surface and showed that chitosan enveloped the functionalized apatite particles surface. The elaborated PCA-APTES-CS functionalized composites exhibited compressive strength similar to the spongy bone. The functionalized biocomposite will be investigated as potential biomaterial for orthopedic application.

Purpose This paper aims to address the production of biocomposite nanofibers using luffa natural fibers and polyaniline conductive polymer/polyethylene oxides (PANI/PEO). Design/methodology/approach In this study, luffa natural fibers are extracted by chemical method. After mixing the treated luffa (TL) with the PANI/PEO solution, TL/PANI/PEO nanofibers were produced by electrospinning (ES) method under different ES parameters to examine the optimal conditions for nanofiber production. Then TL/PANI/PEO biocomposite nanofibers prepared in different weight ratios were produced to analyze the effects of luffa in the morphology and thermal properties of the biocomposite nanofibers. The characterization analysis of TL/PANI/PEO biocomposite nanofibers was performed by scanning electron microscopy, Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) analysis methods. Findings The analysis shows that different weight ratios of TL to PANI/PEO changed the morphology of the membrane. When increasing the weight ratio of TL, the morphological structure of TL/PANI/PEO transformed from nanofiber structure to thin film structure. The appearance of O—H peaks in the FTIR results proved the existence of TL in PANI/PEO nanofibers (membrane). Moreover, an increase in the weight ratio of luffa from 2% to 7.5% leads to an increase in the peak intensity of the O—H group. Regarding DSC analysis, biocomposite nanofibers improved the thermal properties. According to all results, 2%wt TL/PANI/PEO showed optimal morphological properties. Originality/value Plant cellulose was extracted from the luffa, one of the natural fibers, by method of alkali treatment. A new type of biocomposite nanofibers was produced using TL blend with PANI via electrospinning method.

The development of biodegradable materials as food packaging material is important not only due to the reduction in environmental pollution but also because of an improvement in the functionality. Rice husk-reinforced biopolymers have offered a possible solution to waste-disposal problems associated with traditional petroleum-derived plastics. Rice husk-reinforced low density polyethylene (LDPE)-based biocomposites have been of great interest for their use as food packaging material. In this work, the LDPE/RH biocomposites with different rice husk (RH) content (10, 20, 30, 40 and 50 wt.%) were prepared by the melt mixing process in a laboratory Brabender mixer. The effect of RH content on the physical, thermal and mechanical properties of LDPE was investigated. More importantly, this work aimed to research the biodegradation of the LDPE/RH biocomposites as well as their effect on ‘Granny Smith’ apples’ respiration. The results showed that the incorporation of RH into the LDPE decreased the thermal stability of LDPE, increased water vapour permeability and water absorption, and increased the degree of crystallinity. The incorporation of RH increased the biodegradability of LDPE as well as the postharvest quality of ‘Granny Smith’ apples. The addition of RH in LDPE film significantly decreased fruit respiration and increased firmness as compared to LDPE film. The composting results showed that after the LDPE/RH biocomposite films were biodegraded for 21 days, the biocomposite films with the highest content of rice husks were the most degraded.

Aiming to adds value to agricultural products and develop environmental-friendly and cost-effective materials, the present work investigates the influence of babassu mesocarp (BM) flour extractives and the addition of maleic anhydride-modified polyethylene (MAPE), as a coupling agent, on the properties of additivated polyhydroxybutyrate (PHBad)/BM biocomposites. The extractives were partially and completely removed from BM flour by detergent and soxhlet extraction, respectively, before biocomposites melt processing. The thermal, mechanical, structural, morphological, and flow properties of biocomposites with extracted BM flours were determined and compared to the properties of biocomposite with BM flour in natura. In addition, the influences of MAPE incorporation in the properties of each biocomposite were also studied, in order to understand their role in biocomposite compatibilization. The particle treatments resulted in biocomposites with lower tensile strength than biocomposites with BM in natura. Despite the low compatibility of MAPE with PHB, the addition of MAPE increased the tensile strength of the respective PHB biocomposite, reaching values of tensile strength similar or slightly higher than the PHBad-MAPE matrix. Therefore, MAPE acted as an effective additive for BM flour, probably, due to reactive processing with the starch polar surface groups. Since BM was abundantly and cheaply available, its use with PHB and MAPE resulted in biodegradable material with similar mechanical properties of neat PHB and concomitant reduction in cost.

Use of agricultural waste for biocomposite is one of the main concerns of researchers because the waste is an abundant, economic, and eco-friendly source. Agro wastes of Cymbopogon flexuosus plant shoot (CFPS) from an oil extraction industry was analyzed for its feasibility as reinforcement in a metal matrix composite and as a lignocellulosic filler in a polymer matrix composite. In this study, non-carbonized and carbonized CFPS wastes were characterized by using a combination of spectroscopic and chemical techniques. The carbonized CFPS is rich in SiO2 along with other traces of hard ceramic particles as authenticated by X-ray fluorescence, X-ray diffraction, and Energy Dispersive X-Ray Spectroscopy. The presence of siloxane and silanol elemental groups was also confirmed by Fourier transform infrared spectroscopy data. Similarly, Fourier transform infrared and the X-ray diffraction spectroscopy analysis on powdered non-carbonized CFPS waste confirmed the semi-crystalline nature of the CFPS with a higher crystallinity index. Moreover, the non-carbonized CFPS had a rough surface, as confirmed by atomic force microscope and scanning electron microscope analyses. Hence, the experimental data highlighted the feasibility of the CFPS waste as filler and a substitute for silica-based inorganic fillers/reinforcement for composites in enhancing its properties.

The rGO/hemoglobin/CdS biocomposite (rGO/Hb/CdS) were prepared via a simple route. The water-soluble rGO/CdS composite was synthesized in aqueous solution with a facile hydrothermal route. CdS nano...

The present work reported the preparation of biocomposites based on poly(3-hydroxybutyrate) (PHB), plasticizer, and bacterial cellulose (BC) by melt processing and their testing by means of thermal properties (DSC), water absorption, and in vitro degradation. The surface of the biocomposites was analyzed via atomic force microscopy (AFM). In vitro degradation of the biocomposites was evaluated by weight loss and thermal properties (DSC) assessment after the immersion of the specimens in phosphate-buffered saline solution (PBS of pH 7.4) over 20 days. The results showed that the BC can reduce the PHB crystallinity and promote its degradation under PBS medium. Moreover, it was found that the water absorption increased as the percentage of BC increased.

This study presents a method for synthesizing hydroxyapatite (HA) with high crystallinity at low temperatures using a small amount of graphene oxide (GO), and the characters of produced GO/crystalline HA complex was investigated. The morphology and components of the synthesized HA (i.e., HA/GO) were analyzed through scanning electron microscopy, X-ray diffraction and transmission electron microscopy; additionally, the yield of the HA/GO was assessed. The HA/GO results were analyzed by comparing them with those obtained using HA synthesized without GO as a control group. A yield of ~4 mg of HA/GO was attained by the use of 100 μg of GO, demonstrating 20% improvement over the control group. The crystal phase analysis confirmed that crystalline HA of fine quality with nano-size was simply synthesized without intermediate phases using adding a small amount of GO, and the synthesized HA without GO is consist of intermediate phases (brushite and octacalcium phosphate) and hydroxyapatite. Biological characteristics of HA/GO were assessed through the behavioral analysis of mesenchymal stem cell attachment, proliferation, differentiation, and its protein adhesion capacity. HA/GO exhibited excellent biocompatibility and osteogenic differentiation behavior together with better protein adhesion ability than HA. These results demonstrate potential of HA/GO for application in bone tissue engineering. Thus, HA/GO can be developed as a biomimic biocomposite by combining it with bioactive molecules such as growth factors.

In this study, we reported the development of Prussian blue (PB), poly(pyrrole-2-carboxylic acid) (PPCA), and glucose oxidase (GOx) biocomposite modified graphite rod (GR) electrode as a potential biocathode for single enzyme biofuel cell fuelled by glucose. In order to design the biocathode, the GR electrode was coated with a composite of PB particles embedded in the PPCA shell and an additional layer of PPCA by cyclic voltammetry. Meanwhile, GOx molecules were covalently attached to the carboxyl groups of PPCA by an amide bond. The optimal conditions for the biocathode preparation were elaborated experimentally. After optimization, the developed biocathode showed excellent electrocatalytic activity toward the reduction of H2O2 formed during GOx catalyzed glucose oxidation at a low potential of 0.1 V vs Ag/AgCl, as well as good electrochemical performance. An electrocatalytic current density of 31.68 ± 2.70 μA/cm2 and open-circuit potential (OCP) of 293.34 ± 15.70 mV in O2-saturated 10 mM glucose solution at pH 6.0 were recorded. A maximal OCP of 430.15 ± 15.10 mV was recorded at 98.86 mM of glucose. In addition, the biocathode showed good operational stability, maintaining 95.53 ± 0.15% of the initial response after 14 days. These results suggest that this simply designed biocathode can be applied to the construction of a glucose-powered single enzyme biofuel cell.

Fibrous scaffold along with seed cells are essential players for engineered tissue regeneration. Recently, PLGA/epoxidized poly(isoprene) dense membranes have been evaluated for cell growth and have shown satisfactory results. However, porous and fibrous structures suitable for obtaining 3D supports have not yet been evaluated for the PLGA/epoxidized poly(isoprene). The present work aimed to establish the electrospinning conditions for obtaining electrospun membranes with a smaller diameter of fibers and adequate morphology, which were characterized in vitro by their physical, chemical and biological properties. The best electrospun fibers were obtained from the following conditions: an applied voltage of 15 kV, a needle-collector distance of 20 cm and, a flow rate of 5 mL/h. The functional groups of the polymers involved in the blend did not show any changes. The mechanical properties of the electrospun membranes are within the lower limits known to human skin and some soft tissues. The in vitro degradation test showed a loss of mass of approximately 20% in 28 days. Significant adhesion and proliferation of human adipose–derived mesenchymal stem cells were demonstrated, indicating that there was cellular penetration into the scaffold and proliferation. Therefore, the preliminary results suggest that the electrospun PLGA/epoxidized poly(isoprene) membranes have high potential for application as a 3D tissue engineering scaffold.

The aim of this study is to evaluate the biodegradable packaging materials which will be an alternative to traditional synthetic packaging materials. For this purpose, packaging films containing polycaprolactone (PCL), montmorillonite (MMT), and organically modified montmorillonite (OMMT) were prepared by solution casting method, and the mechanical, physical, structural, antimicrobial, and antifungal properties of these films were examined. Cetyl trimethyl ammonium bromide (CTAB) was used for the modification of montmorillonite. The structural properties of the prepared films were characterized by attenuated total reflection-Fourier transform infrared, X-ray powder diffraction, thermogravimetric analysis, and scanning electron microscopy. The PCL/OMMT structure was found to be thermally more stable than the PCL/MMT structure. The addition of OMMT to PCL improved the thermal and mechanical properties of the films compared with the pure PCL and PCL/MMT films. In addition, adding MMT/OMMT to the PCL caused an increase in the hardness of the films. In the antimicrobial analysis, while no inhibition effect was observed in PCL/MMT films, PCL/OMMT films showed inhibition effect against Staphylococcus aureus. Antifungal tests performed with the prepared films showed that the film-wrapped bread did not deteriorate for 40 days. It is thought that PCL/MMT and PCL/OMMT films prepared in this study will provide an advantage in applications as packaging material.

The current work mainly focuses on the innovative nature of nano-gallium-substituted hydroxyapatite (nGa-HAp)/Pergularia daemia fiber extract (PDFE)/poly(N-vinylcarbazole) (PVK) biocomposite coating on titanium (Ti) metal in an eco-friendly and low-cost way through electrophoretic deposition for metallic implant applications. Detailed analysis of this nGa-HAp/PDFE/PVK biocomposite coating revealed many encouraging functional properties like structure and uniformity of the coating. Furthermore, gallium and fruit extract of PDFE-incorporated biocomposite enhance the in vitro antimicrobial, cell viability, and bioactivity studies. In addition, the mechanical and anticorrosion tests of the biocomposite material proved improved adhesion, hardness, and corrosion resistance properties, which were found to be attributed to the presence of PDFE and PVK. Also, the swelling and degradation behaviors of the as-developed material were evaluated in simulated body fluids (SBF) solution. The results revealed that the as-developed composite exhibited superior swelling and lower degradation properties, which evidences the stability of composite in the SBF solution. Overall, the results of the present study indicate that these nGa-HAp/PDFE/PVK biocomposite materials with improved mechanical, corrosion resistance, antibacterial, cell viability, and bioactivity properties appear as promising materials for biomedical applications.

A biocompatible hydrogel is ideal for tissue engineering and regeneration. In this study, methacrylated keratin (KerMA) was synthesized for the first time and then blended with poly(ethylene glycol dimethacrylate) (PEGDMA) to form hydrogel through photocrosslinking. The chemical structure, gelation time, swelling behavior, hydrophilicity, cytotoxicity, and 3D printability of PEGDMA/KerMA hydrogels were characterized and exploited. The PEGDMA/KerMA hydrogels performed good cytocompatibility, providing potential applications for tissue engineering and regenerative medicine.

The polymeric scaffolds are one of the most studied systems for biomedical applications. Yet, their enzymatic degradation and non-antibacterial ability are the major challenges for the researchers. In this regard, we designed Fe(III) doped ZnO integrated hydroxyapatite ZFHAp nanoparticles and prepared the natural biopolymer-based chitosan- carboxymethyl cellulose-ZFHAp scaffolds suitable for bone tissue engineering. The nanoparticles were successfully characterized with XRD and RAMAN spectroscopy and were found to be in hexagonal wurtzite HAp phase with Ca + Zn + Fe/P ratio of 1.7. The prepared nano-biocomposite scaffolds were microporous in structure (25–123 µm), and their biochemical behaviours such as porosity (60–80%), swelling, and enzymatic degradation (21–50%) were dependent on the concentrations of ZFHAp. The swelling and degradation of the prepared scaffolds were linearly related. The presence of 5% ZFHAp in the scaffolds (SCA-5) resulted in pore size of 92 ± 10 µm and 50% degradation time of 42 days. This scaffolds SCA-5 also showed self-antibacterial activities along with excellent cell proliferation ability. The present study designates the SCA-5 as plausible scaffolds for bone tissue engineering.

Mango seed husks were fractionated to obtain hemicellulose extracts with varied xyloglucan (XGN) and xylan (XLN) ratios that suit the formulation of thermally stable and self-supporting films. A strategy for obtaining the suitable XGN/XLN composition involved optimizing extraction temperatures (40–90 °C), NaOH concentrations (1–2 M), and time (2–4 h) in central composite design experiments, based on the yield, XGN/XLN ratio, uronic acid, and lignin contents. Through desirability analysis, the optimal process conditions (1.92 M NaOH, 86.0 °C, and 3.84 h) for suitable XGN/XLN composition were achieved, which gave hemicellulose yield, XGN/XLN ratio, uronic acids, lignin, and Zeta potential of 46.24%, 0.13, 12.02%, 16.73%, and − 16.1 mV, respectively. Permethylation analysis and Gas chromatography/Mass spectroscopy confirmed the presence of 1,4 linked glucan backbone for xyloglucan in the hemicellulose, with xylose residues branching at the non-reducing end. The molecular weight and maximum degradation temperature of the hemicellulose extract were higher (70,189 g mol−1 & ≈ 330 °C, respectively) than of beechwood XLN (27,235 g mol−1 & 290 °C, respectively). The hemicellulose extract formed self-supporting thermally stable (290 °C) biocomposite films, with potential application in food packaging. Customizing extraction of the hemicellulose with tunable functional properties, from the mango seed husk, is a novel approach for value addition to food waste that can be integrated into a biorefinery set-up.

Nowadays, there is a need to obtain eco-friendly materials, especially plastics that are responsible for most of the environmental pollution. In this regard, poly(ɛ-caprolactone) PCL biocomposites with 10wt% of the oil (O) and/or 10wt% of the flour (F) extracted from the macaiba almond were produced in order to carry out a study of this polymer biodegradation acceleration. Mechanical properties (impact, traction and flexural), differential scanning calorimetry (DSC), thermogravimetric (TGA), water absorption, contact angle and analysis by optical microscopy (OM) and scanning electronics (SEM) were evaluated. Through these analyzes, it was noted that in the PCL–O biocomposite, the oil acted as a plasticizer in the PCL and in the PCL–FO biocomposite, there was an interaction among both phases. The samples biodegradation took place in accordance with ASTM G160-03 by burying impact specimens in compost for 60 days. The PCL–F biocomposite showed a mass loss of approximately 45%, followed by PCL–FO, with a loss of approximately 25%, both compositions also presented a rough morphology, with cracks and pores presence due to biodegradation from the microorganism action. These results have shown that the flour obtained from the macaiba almond is a promising agent for accelerating the PCL biodegradation.

Antibacterials have been used to treat infectious diseases in both humans and animals since 1929. Along with their use, there is resistance to some antibacterials. 43% of Escherichia coli is resistant to various types of antibiotics. Therefore, research on the development of antibacterial ingredients is always being developed. Nanocellulose has received a lot of attention on its application of antibacterial material support. Meanwhile, chitosan is an antibacterial biopolymer with a brittle structure, hence nanocellulose is added to chitosan film to increase its structural stability. In this study, nanocellulose was extracted from sugarcane bagasse through a combination method of sulfuric acid hydrolysis with ultrasonic waves. The effect of addition of nanocellulose to chitosan mechanical properties was investigated. Scanning Electron Microscopy (SEM) characterization showed that there were differences in morphology between nanocellulose, chitosan, and nanocellulose-chitosan biocomposites. The result of X-Ray Diffraction and Fourier-transformed infrared spectroscopy analysis showed that biocomposites was successfully formed. The average size of nanocellulose particle was 132.67 nm. Nanocellulose-chitosan biocomposites with a ratio of 10:2 have the best antibacterial activity against Escherichia coli than other biocomposite ratios.

Concerns about environmental problems have led to the development of biodegradable packaging. Food wastes as a byproduct could be a good source for biopolymers. This study aimed to describe the physical and antimicrobial features of nano biocomposite films based on orange waste powder (OWP) with different concentrations of nettle essential oil (NEO) (1.5 and 3%) as an antibacterial agent and cellulose nanofiber (CNF) (3 and 6%) as a structural reinforcement. Thus, Field emission scanning electron microscopy (FE-SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and differential scanning calorimetry analysis (DSC) were performed. Further, tensile strength, elongation at break, water vapor permeability, and antimicrobial properties were investigated. As a result, the addition of CNF improved the tensile strength and water barrier properties of the samples. Compared to the control film, adding NEO (3%) decreased the tensile strength but increased water vapor permeability and melting temperature. Moreover, the OWP-based film samples had an antimicrobial effect against five foodborne pathogens; this effect was increased considerably by enhancing the NEO concentration. In this regard, the maximum and minimum susceptibility was related to the Staphylococcus aureus and Salmonella enterica, respectively. In conclusion, orange waste could be used to produce an active film with improved physicomechanical and antibacterial properties by incorporating CNF and NEO.

We developed a novel BW-CS/ZnHA biocomposite utilizing Beeswax-Chitosan and Zinc-hydroxyapatite nanoparticles (ZnHAP). The uniformed mixture of beeswax-chitosan and ZnHAP was freeze-dried to get a porous biocomposite. The fabricated biocomposite was characterized using FTIR, XRD, and SEM. Moreover, the antibacterial, swelling, biodegradations, viability, and cell proliferation capacity of the fabricated biocomposite was assessed. The biocomposite demonstrated upgraded swelling and antibacterial activity. The addition of ZnHAP accomplished the antibacterial activity. Biocompatibility studies were carried out using osteoblast cells and thus we proved the non-toxic nature of the biocomposite. Osteoblast cell adhesion investigations demonstrated that the cells were appended and infiltrated into the inside of the biocomposite. The obtained results encourage the use of these bandages for various types of wounds with infection and exudates.

Golden glittering biocomposite fibers from poly(lactic acid) (PLA) and nanosilver-coated titanium dioxide (Ag/TiO2) were successfully prepared via a melt spinning process. Various contents of 10% Ag/TiO2/PLA masterbatch were diluted with PLA in concentrations of 5, 10, 15, 20, 25, and 30 phr, respectively. The physical, mechanical, thermal, and antibacterial properties of the obtained fibers were investigated. The results indicated that the glittering biocomposite fiber had a light, yellow-gold color and a slightly rough surface. Tenacity and elongation at break of the glittering biocomposite fibers were lower than those of the pristine PLA fiber. The thermal properties of the glittering composite fibers also decreased with increasing masterbatch content. The PLA/PEG-10 biocomposite fiber with good spinnability and mechanical properties was suitably used for preparing the golden glittering composite fabric by the knitting process. Moreover, the golden glittering biocomposite fabrics exhibited antibacterial activity against certain microbes, for example, Staphylococcus aureus, Bacillus subtilis, and Candida albicans. The prepared fabric has significant potential for use in eco-friendly textile products and antibacterial fabrics. Besides, our novel textiles showed not only the photocatalytic property needed to degrade organic dyes such as methylene blue in water but also the ion-sensing property for mercury(II) ions by changing the textile color from yellow to colorless.

Thermoplastic starch (TPS), as a natural based polymer, is known to have the capability to be used in biological applications due to its biocompatibility and biodegradability. In this study, mechanical properties of TPS are enhanced by incorporating bioactive β-tricalcium phosphate (β-TCP) particles for bone tissue engineering applications. Starch-based nanocomposites containing 3, 5, and 10 wt% of β-TCP nanoparticles (TT3, TT5, TT10) were made using a co-rotating twin-screw extruder. Dynamic light scattering (DLS) and X-ray diffraction (XRD) techniques were employed to analyze the nanocomposites. Moreover, degradability, swelling degree, and biomineralization in a simulated body fluid (SBF) were studied. To investigate the dispersion of β-TCP nanoparticles in the composite and biomineralization of the nanocomposites after incubation in SBF, scanning electron microscopy (SEM) and energy dispersive X-Ray analysis (EDX) were performed. Evaluation of mechanical properties of TPS and nanocomposites demonstrated that increase in β-TCP content enhanced mechanical properties. Besides, the bioactivity of these three nanocomposite materials was proven by nucleation of hydroxyapatite on the samples’ surface after incubation in simulated body fluid (SBF). Cytotoxicity test was done as well. Results of the current study have paved the way for the application of TPS/β-TCP composite as bone tissue engineering material.

Supported metal catalysts, for instance, palladium, are one of the foundations of chemical reactions, especially in C–C bond formation. The present study reports preparation of a magnetically separable palladium-supported nano-biocomposite with a low cost and easy immobilization technique. Fibroin, a natural biodegradable polymer, was used through an in situ method to cover the Fe3O4 nanoparticles to make a nano-biocomposite followed by anchoring palladium on the fibroin surface. The morphology and the structure of palladium-supported nano-biocomposite Fe3O4@fibroin-Pd were characterized by FT-IR, XRD, TGA, SEM, EDX, and TEM techniques. Consequently, the nanocatalyst activity was evaluated in the Heck coupling reactions. Only a very small amount of the nanocatalyst was employed in the reaction, and it showed excellent catalytic activity; in most cases more than 90% efficiency. The significant advantages of employing this nanocatalyst include high catalytic activity, short reaction times, easy separation of the nanocatalyst with an external magnet and great reusability. The results demonstrated that the used nanocatalysts were very active for four consecutive reaction rounds.

In this study, a light cross-linkable biocomposite scaffold based on a photo-cross-linkable poly (propylene fumarate) (PPF)-co-polycaprolactone (PCL) tri-block copolymer was synthesized and characterized. The developed biodegradable scaffold was further modified with β-tricalcium phosphate (β-TCP) bioceramic for bone tissue engineering applications. The developed biocomposite was characterized using H nuclear magnetic resonance and Fourier transform infrared spectroscopy. Moreover, the bioceramic particle size distribution and morphology were evaluated using Brunauer-Emmett-Teller method, X-ray diffraction, and scanning electron microscopy. The mechanical properties and biodegradation of the scaffolds were also evaluated. Cytotoxicity and mineralization assays were performed to analyze the biocompatibility and bioactivity capacity of the developed biocomposite. The characterization data confirmed the development of a biodegradable and photo-cross-linkable PCL-based biocomposite reinforced with β-TCP bioceramic. In vitro analyses demonstrated the biocompatibility and mineralization potential of the synthesized bioceramic. Altogether, the results of the present study suggest that the photo-cross-linkable PCL-PPF-PCL tri-block copolymer reinforced with β-TCP is a promising biocomposite for bone tissue engineering applications. According to the results, this newly synthesized material has a proper chemical composition for further clinically-relevant studies in tissue engineering.

2,2,6,6-Tetramethylpiperidin-1-yl oxyl (TEMPO)-oxidized beta-chitin nanofibrils (T-ChNF) are novel nanofibrils of high strength and stiffness and can also enhance the adsorption of chitosan in mate ...

The ultimate goal of this paper is to develop novel ceramic-polymer-based biocomposite orthopedic scaffolds with the help of additive manufacturing. Specifically, we incorporate a bioceramic known as amorphous magnesium phosphate (AMP) into polylactic acid (PLA) with the help of the melt-blending technique. Magnesium phosphate (MgP) was chosen as the bioactive component as previous studies have confirmed its favorable biomaterial properties, especially in orthopedics. Special care was taken to develop constant diameter AMP-PLA composite filaments, which would serve as feedstock for a fused filament fabrication (FFF)-based three-dimensional (3D) printer. Before the filaments were used for FFF, a thorough set of characterization protocols comprising of phase analysis, microstructure evaluations, thermal analysis, rheological analysis, and

The effect of silane A-174 (3-(trimethoxysilyl)propyl methacrylate (methacryloxypropyl trimethoxysilane)) modifications of the ceramic surface on the structural characteristics and mechanical perfo...

This paper reports the effect of lignocellulosic flour and talc powder on the thermal degradation behavior of poly (lactic acid) (PLA) by thermogravimetric analysis (TGA). Lignocellulosic flour was obtained by grinding Opuntia Ficus Indica cladodes. PLA/talc/ Opuntia Ficus Indica flour (OFI-F) biocomposites were prepared by melt processing and characterized using Wide-angle X-ray scattering (WAXS) and Scanning Electron Microscope (SEM). The thermal degradation of neat PLA and its biocomposites can be identified quantitatively by solid-state kinetics models. Thermal degradation results on biocomposites compared to neat PLA show that talc particles at 10 wt % into the PLA matrix have a minor impact on the thermal stability of biocomposites. Loading OFI-F and Talc/OFI-F mixture into the PLA matrix results in a decrease in the maximum degradation temperature, which means that the biocomposites have lower thermal stability. The activation energies (Ea) calculated by the Flynn Wall Ozawa (FWO) and Kissinger Akahira Sunose (KAS) model-free approaches and by model-fitting (Kissinger method and Coats-Redfern method) are in good agreement with one another. In addition, in this work, the degradation mechanism of biocomposites is proposed using Coats-Redfern and Criado methods.

Agricultural crop residues are known to be a renewable source of value-added products, and their application as a bio-based production chain type in the circular bioeconomy system is considered efficient in minimizing environmental problems. Value-added products, such as cellulose nanofibers (CNFs) from lignocellulose in agriculture residues, have been widely applied in the production of membranes that have desirable physicochemical characteristics. In this work, orange bagasse residue was used to obtain cellulose nanofiber and then applied to starch membranes as a mechanical reinforcement. The 1-methylimidazolium ionic liquid was used as biomass treatment for cellulose nanofiber isolation, and then two starch membranes were prepared with 5% (v/v) of cellulose nanofiber solution at 70 °C and 90 °C by the casting method. The cellulose nanofibers and membranes were characterized by scanning electron microscopy, fourier transform infrared spectroscopy, thermogravimetric analysis, and X-ray diffraction. Thickness and tensile tests were applied to the membranes. Cellulose nanofibers less than 100 nm in diameter were obtained by the 1-methylimidazolium treatment, and the characterization analyses showed that the CNFs were incorporated into the membranes, which improved their mechanical resistance and thermal degradation capacity. However, membrane 1, which was prepared at 70 °C, showed a particularly significant gain in tensile strength.

In this prelude study, the gellan gum/kenaf core fiber (KCF) biocomposite films were fabricated with the addition of imidazolium-based ionic liquids such as 1-butyl-3-methylimidazolium chloride (Bmim Cl), 1,3-dimethylimidazolium methylsulphate (Dmim MeSO4), 1-ethyl-3-methylimidazolium acetate (Emim Ac), and 1-ethyl-3-methylimidazolium trifluoromethanesulfonate (Emim OTf). The fabrication of the biocomposite films was carried out by mixing KCF and the ionic liquids in an aqueous solution, followed by dissolution of gellan gum in the same solution at a temperature of 90°C. The mixed solution was gelled at room temperature, and the formed gel was dried in an oven at 40°C for 48 hours to obtain a freestanding biocomposite film. The fabricated films were characterized by using a universal testing machine to acquire tensile properties. The tensile test results indicated that the biocomposite film added with Emim Ac possesses a higher tensile extension at maximum (up to 24%) than the biocomposite film without ionic liquid (added with glycerol). In addition, the biocomposite film added with Emim OTf has a higher tensile modulus at maximum (up to 758%) compared to the biocomposite film without ionic liquid. In conclusion, the tensile properties of the gellan gum/KCF biocomposite films can be improved with the addition of Emim-based ionic liquids with different counter anions.

The use of nanostructured materials is already well-known as a powerful tool in the development of electrochemical sensors. Among several immobilization strategies of nanomaterials in the development of electrochemical sensors, the use of low-cost and environmentally friendly polymeric materials is highlighted. In this context, a new nanostructured biocomposite electrode is proposed as an electrochemical sensor for the analysis and determination of tetracycline. The composite electrode consists of a modified glassy carbon electrode (GCE) with a nanodiamond-based (ND) and manioc starch biofilm (MS), called ND-MS/GCE. The proposed sensor showed better electrochemical performance in the presence of tetracycline in comparison to the unmodified electrode, which was attributed to the increase in the electroactive surface area due to the presence of nanodiamonds. A linear dynamic range from 5.0 × 10 − 6 to 1.8 × 10 − 4 mol L−1 and a limit of detection of 2.0 × 10 − 6 mol L−1 were obtained for the proposed sensor. ND-MS/GCE exhibited high repeatability and reproducibility for successive measurements with a relative standard deviation (RSD) of 6.3% and 1.5%, respectively. The proposed electrode was successfully applied for the detection of tetracycline in different kinds of water samples, presenting recoveries ranging from 86 to 112%.

Urea–formaldehyde (UF) resins are often reinforced with natural fibers or nanostructures such as cellulose microfibrils (CMFs) to improve their mechanical and physical properties in wood panels. However, the high-water content in these suspensions is a limitation on applications in thermosetting resins. The innovative technology investigated here consists of the in-situ production of a methanediol-based suspension of CMFs through a mechanical process and its incorporation during resin synthesis. We sought to maintain the physicochemical properties and the basic chemical composition of the resin. The synergy between the resin and CMFs provided a shielding effect and a greater storage modulus (E’). We demonstrate that this approach is robust through standard viscoelastic, physical, and mechanical tests. Likewise, a methanediol-based CMF suspension used to synthesize UF resin was effective to reduce formaldehyde emission during the resin cure reactions. Finally, the bio-based composites manufactured with this UF resin containing CMF had better performance due to increased internal bond strength by up to 15%, reduced water absorption by up to 8%, and reduced formaldehyde emission by 30% at environmental temperature.

Clove essential oil (CEO) was immobilized in mesoporous silica nanoparticles (MSN) (0, 1, 2, and 3 wt%) and incorporated into poly(lactic acid) (PLA) matrix via a casting method. The functional properties including mechanical property, thermal property, antimicrobial property, and CEO release behavior of the PLA nanocomposite film were investigated. The compatibility of CEO-loading MSN with PLA was verified by scanning electron microscopy analysis. The tensile strength, tensile module, and glass transition temperature of the MSN/CEO/PLA composite film was improved with the increase in MSN content. The release study indicated that the MSN/CEO/PLA composite films exhibited sustained release profile of CEO. The MSN/CEO/PLA films demonstrated efficient antimicrobial activity. The results indicated that CEO immobilized MSN incorporated PLA nanocomposite film showed promising features for active food packaging material.

In the present communication, an anionic surfactant, sodium dodecylbenzenesulfonate (SDBS) and a cationic surfactant tetradecyltrimethylammonium bromide (TTAB) were employed as soft templates for t...

In this study we have recycled two types of waste papers, newspapers and magazines, to prepare paperboard sheets for multipurpose applications. The recycling procedure succeeded in removing most of inorganic contaminants via de-inking process. To enhance the flame retardant ability of paperboard sheets, treatment with varying concentrations (1, 3 and 5 % wt/vol) of organophosphorus-silane compound in the absence and presence of starch (0.2 % wt/vol) was done. The thermal proofing properties of paperboard sheets have been modified after treatment with organophosphorus-silane compound and starch/organophosphorus-silane biocomposite. The results showed that, 3 % (wt/vol) was the minimum concentration to accomplish fire retardancy of paperboard sheets. The addition of starch to the organophosphorus-silane compound enhances the physicomechanical properties of modified paperboard sheets. The paperboard sheets treated organophosphorus-silane compound and starch/organophosphorus-silane biocomposite showed dissimilar activities against Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. Various analyses were performed to study the physical, chemical, mechanical and thermal properties of the prepared paperboard sheets.

Sustainable biocomposites have been developed from poly (3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) by solution-casting using montmorillonite (MMT) and acetylated cellulose nanocrystals (ACNs) as reinforcing agents. The morphological, thermal, crystallization behavior, tensile and barrier properties of biocomposites (A@MP) were evaluated. The morphological characterizations revealed the improved dispersion of ACNs in A@MP matrix. The ternary biocomposite showed up to 63.4% and 49 °C improvements in tensile strength and the maximum thermal decomposition temperature, respectively, compared to those of neat PHBH. Furthermore, the oxygen permeability (OP) and water vapor permeability (WVP) of A@MP with 2.5wt% ACN loading reached 0.60 × 103 mL·μm/m2·d·atm and 1.06 × 10–8 g/m·d·Pa, respectively. Overall, the research results have demonstrated the high potential of PHBH ternary biocomposite for food packaging applications.

In the present study, the potential use of cellulosic microfibers (CMFs) extracted from hemp fiber (HF) and pulp and paper solid waste (mixed sludge (MS), deinked sludge (DS)) as a reinforcing agent in novel bio composite materials produced from recycled Polylactic acid (rPLA) was investigated. CMFs were extracted and treated using physicochemical method followed by enzymatic treatment with laccase and cellulase. The effects of CMFs concentrations (1.5, 3 and 6% w/w) and fiber size (75 μm–1.7 mm) on the mechanical properties (impact and tensile) and biodegradability of the biocomposite samples were investigated. A modified interfacial adhesion between rPLA matrix and the three fibers used, was clearly observed through mechanical tests due to alkali and enzymatic treatments. The use of different types of enzymatically treated cellulosic fibers for polylactic acid (PLA) recycling was assessed by Scaning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The combined physicochemical and enzymatic treatments led to a considerable size reduction of the cellulosic fibers (HF, MS and DS) resulting in the enhanced interfacial adhesion between rPLA matrix and fibers. The biocomposite obtained with rPLA with HF gave the most favorable values for Young’s modulus (324.53 ± 3.10 MPa, p-value 0.03), impact strength (27.61 ± 2.94 kJ/m2, p-value 0.01) and biodegradation rate (1.97%).

Fabric dyeing produces high amounts of wastewater containing organic and inorganic pollutants such as reactive dyes that are the most common textile dyes employed by the industry. Three vinylsulfonic reactive dyes, blue 19 (B-19), red 198 (R-198), and yellow 15 (Y-15), were removed from effluents of industrial-like dyeing processes employing three adsorbents: (1) magnetite nanoparticles (MNP), (2) yeast waste obtained after β-glucan removal from yeast biomass (YW), and (3) nanomagnetic composite produced from YW and MNP (YW-MNP). The non-linear kinetic pseudo-second-order and two-stage models best explained the experimental phenomena for the majority of adsorbate:adsorbent systems. The theoretical isotherm models were fitted to experimental isotherms obtained from experiments conducted with appropriated dilutions of effluents, which have a specific condition, limited by the maximum dye concentration established by the dye recipe. Thus, the saturation of adsorbents was not reached for all adsorbate:adsorbent systems. In this way, the best conditional sorption capacities (SCcond) were obtained by YW (1.7, 2.3, and 2.5 g/kg for B-19, R-198, and Y-15, respectively). The SIPS model best described all dyes adsorbed by YW, while the D-R model best described the phenomena for MNP and YW-MNP.