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Biodegradable bioplastics provide a promising solution to mitigate environmental harm from petroleum-based plastics. This study focuses on optimizing bioplastic films made from oil palm trunk starch (OPTS), using glycerol (10, 20, and 30 % v/w) as a plasticizer and modified with citric-acid epoxidized palm oil (CEPO). The bioplastics were formed using the solution casting method and analyzed for morphology, functional groups, diffraction peaks, thermal and mechanical properties, degradation time, and compostability. The optimal conditions were achieved with 30 % glycerol (Sample ST-CEPO-GLY30). The addition of glycerol enhances the thermal and mechanical properties, improves the biodegradability, and compostability of the bioplastics.

This study aimed to examine the changes in the structural characterization of cross-linked tapioca treated with sodium trimetaphosphate(STMP). The degree of substitution in the cross-linked starch was determined by the iodine absorption method. Scanning electron microscopy, particle size measurement, Fourier-transform infrared spectroscopy (FT-IR), and x-ray diffraction (XRD) were used to characterize the structure of modified tapioca starch at different substitution degrees. The results demonstrated that the degree of substitution of cross-linked starch increased with the increase in the amount of the cross-linking agent. The modified starch particles aggregated to form a mass structure, but the average particle size did not change with the cross-linker content and was about 17 μm. FT-IR and XRD experiments showed that the cross-linking esterification of starch with sodium trimetaphosphate generated new phosphate groups, increasing the content of phosphoric acid in starch, and the A-type crystalline structure of starch was not changed.

Although electrolytes prepared from natural substances have taken up research towards a greener future, practical difficulties in their mechanical and water resistive properties are yet to be addressed by many. In this current paper, a natural gum tragacanth is graft copolymerized with tertiary butyl acrylate utilising glutaraldehyde as the crosslinker and ascorbic acid and potassium persulfate as the initiators. From the TGA analysis, enhanced thermal stability is observed in the crosslinked membrane. The DSC analysis reveals that the crosslinked gum exhibits a glass transition temperature (Tg) of 66 °C and a melting temperature (Tm) of 86 °C. The water uptake of the crosslinked membrane was found to be lower than the pure non-crosslinked membrane. The stress-strain curves of the crosslinked electrolyte showed a tensile strength of 3.58Mpa and a percent elongation of 302%. The effect of the crosslinker glutaraldehyde and the ionic salt lithium nitrate is studied with the help of XRD and FTIR. The electrolyte is characterised to be a good ionic conductive membrane as its conductivity value is found to be 4.72 ×10−4 Scm−1 through EIS measurements. The Arrhenius behaviour of temperature-dependent conductivity was studied and the activation energy values for all the films were calculated.

Lignin is a biomacromolecule with multiple functional groups, which can be used as feedstocks for various functional materials. Lignin microcapsules with the crosslinked shell of lignin have potential applications in various fields. However, the use of toxic organic solvents for preparing lignin microcapsules poses a challenge. In this study, a green solvent called Deep Eutectic Solvent (DES, ChCl-LA) was employed for lignin dissolution. An emulsion of lignin was prepared using soybean oil with the DES dissolving lignin, and crosslinkers like PEGDE or epichlorohydrin facilitated the crosslinking of lignin at the emulsion interface. The resulting lignin microcapsules, with a size of ∼2 μm, were characterized using techniques such as optical microscopy, fluorescence microscopy, scanning electron microscopy, FT-IR, etc. For both NIR imaging and controlled release, the organic molecule BODPY was used as the template. The results demonstrate the successful preparation of size-controlled lignin microcapsules that can serve as nanocarriers for targeted organic molecules

This study examines the development of composite bacterial cellulose (BC) sheets with antimicrobial properties for potential application in face masks. Branched polyethylenimine (PEI) is employed as the antimicrobial agent, effective against both gram-positive and gram-negative bacteria. Various concentrations of PEI are crosslinked into BC via epichlorohydrin under moderate conditions. The thermal and morphological properties of dried BC-PEI samples are comprehensively characterized. Results reveal that introducing PEI via crosslinking minimally impacts the thermal stability of BC, without any discernible physical disruption. Nevertheless, BC-PEI matrices present lower water evaporation enthalpies than BC, based on dynamic scanning calorimetry, caused by alteration of hydrogen bonding interactions (amine groups versus hydroxyl groups). Moreover, dried BC-PEI samples exhibit an improved efficacy against gram-positive bacteria as compared to gram-negative bacteria; S. aureus and P. aeruginosa, respectively. Indeed, a 2.5% (wt/v% of Milli-Q water) PEI concentration completely inhibits the growth of S. aureus after 6 h, while a 7.5% PEI concentration achieves similar effects on P. aeruginosa. Despite the notable antibacterial efficacy of BC-PEI matrices, their antiviral efficacy is less pronounced. This difference in antibacterial and antiviral efficacies could be attributed to variations in microorganism characteristics, mechanisms of action, and structures of PEI.

In this study, Ti3C2Tx/PVA microgels were assembled through the introduction of glutaraldehyde and PVA into Ti3C2Tx colloids. Subsequently, the microgels underwent vacuum-assisted filtration (VAF) and drying processes to fabricate Ti3C2Tx/PVA self-assembled films (MPGF). This research effectively reduced VAF time by introducing a small amount of glutaraldehyde. The findings demonstrate that glutaraldehyde's chemical crosslinking prompts the formation of temporary microgel frameworks between Ti3C2Tx and PVA, enhancing water molecule transfer during VAF and improving film formation efficiency. Further analysis links VAF time is related to the particle size distribution of the microgels. Adjusting crosslinking and PVA quantity alters microgel crystalline structure and –OH hydrogen bonds, affecting particle size and VAF time. Additionally, films produced via rapid VAF exhibit promising mechanical properties for practical applications.

Heavy metals in water bodies pose a significant threat to both ecology and human well-being. Therefore, the development of green and sustainable adsorbents for water remediation is essential. This study presents a crosslinked chitosan composite structure with multiple layers, which was generated by adjusting the ratio of chitosan to wheat straw–derived magnetic biochar in the composite. The adsorption behavior of the composite under different conditions was revealed by varying the Cr(VI) concentration, pH, and temperature. The composite exhibited a maximum adsorption of 121.8 mg g−1 for Cr(VI) in water, which was 11.9 times higher than that of magnetic biochar. It maintained a residual performance of 78.6 % after seven cycles, higher than most chitosan-based composites. The reusability was improved via hydrochloric acid protonation of functional groups and layer-by-layer exposure of the composite structure. This study provides new insights into the application of composites derived from chitosan and wheat straw, an agricultural waste, as sustainable adsorbents.

Pectin hydrogels have emerged as a highly promising medium for the controlled release of pharmaceuticals in the dynamic field of drug delivery. The present review sheds light on the broad range of applications and potential of pectin-based hydrogels in pharmaceutical formulations. Pectin, as a biopolymer, is a versatile candidate for various drug delivery systems because of its wide range of properties and characteristics. The information provided on formulation strategies and crosslinking techniques provides researchers with tools to improve drug entrapment and controlled release. Furthermore, this review provides a more in-depth understanding of the complex factors influencing drug release from pectin hydrogels, such as the impact of environmental conditions and drug-specific characteristics. Pectin hydrogels demonstrate adaptability across diverse domains, ranging from applications in oral and transdermal drug delivery to contributions in wound healing, tissue engineering, and ongoing clinical trials. While standardization and regulatory compliance remain significant challenges, the future of pectin hydrogels appears to be bright, opening up new possibilities for advanced drug delivery systems.

The aim of this study is to analyze the use of vitamin E to enhance fabric's hand feel, moisture management and fabric strength which are affected due to flame retardant finish. Flame retardant treated fabrics typically become stiff, but the addition of Vitamin E along with emulsifier and binding agent through a vertical padding mangle by two times dipping and nipping results a soft fabric without impairing the flammability properties as determined by 45-degree flammability test. The samples were characterized by FTIR spectra, SEM images, and water contact angle. A new characteristics band is appeared at 1455 cm−1 for skeletal vibration of phenyl ring system of alpha tocopherol for Vitamin E measured by Fourier transform infrared spectroscopy (FTIR) that proves the effective attachment of vitamin E with fabric. Hydrophilicity of vitamin E containing sample is discovered after showing 37.629° as a water contact angle at optical tensiometer (Attension theta lite). Additionally, fabric comfort properties, moisture management properties, and mechanical properties were measured by fabric touch tester (FTT), moisture management tester (MMT) machine and tensile strength tester respectively that demonstrate significant affirmative change in almost all indexes of FTT, 43.5 % increase of overall moisture management capacity by MMT and 23 % increase of tear strength by tensile strength tester due to use of vitamin E that effectively compensate lower strength, poor fabric comfort, and low moisture management capability of flame retardant treated fabric.

Pectinolytic enzymes are among the important group of industrial enzymes that have wide applications in different food industries. In this study, pectinase-based silica nanocarriers were synthesized using co-precipitation and cross-linking techniques. The resulting silica nanoparticles were investigated using scanning electron microscopy (SEM), energy-dispersive electron microscopy (EDEX), and X-ray diffraction (XRD) for determination of its morphology, elemental composition, and crystalline pattern. Under the optimal immobilization conditions like 1.5 % glutaraldehyde, 3000 IU/mg pectinase concentration, 90 min immobilization time and 40 °C immobilization temperature, pectinase showed maximum immobilization yield. The immobilization of pectinase onto the silica nanocarriers led to enhanced catalytic characteristics, displaying higher enzymatic activity across various temperature and pH levels compared to soluble pectinase. Moreover, the immobilization substantially improved the temperature stability of pectinase, exhibiting 100 % of its initial activity even after 120 h of pre-incubation at 50 °C. Additionally, the silica nanocarrier pectinase retained 100 % of its original activity even after being reused 10 times in a single batch of reactions. These findings indicate that the immobilization of silica nanocarriers effectively enhances pectinase's industrial capabilities, making it economically feasible for industrial use and an efficient system for various biotechnological applications.

The complicated chemical reactions involved in the production of the newer drug delivery systems have mainly impeded efforts to build successful targeted drug delivery systems for a prolonged duration of time. Nanosponges, a recently created colloidal system, have the potential to overcome issues with medication toxicity, decreased bioavailability, and drug release over a wide area because they can be modified to work with both hydrophilic and hydrophobic types of drugs. Nanosponges are small sized with a three-dimensional network having a porous cavity. They can be prepared easily by crosslinking cyclodextrins with different compounds. Due to Cyclodextrin's outstanding biocompatibility, stability, and safety, a number of Cyclodextrin-based drug delivery systems have been developed promptly. The nanosponge drug delivery system possesses various applications in various ailments such as cancer, autoimmune diseases, theranostic applications, enhanced bioavailability, stability, etc. This review elaborates on benefits and drawbacks, preparation techniques, factors affecting their preparation, characterization techniques, applications, and most current developments in nanosponges.

Extrusion-based 3D bioprinting (EBBP) prints tissues, including nerve guide conduits, bone tissue engineering, skin tissue repair, cartilage repair, and muscle repair. The EBBP demands optimized parameters for obtaining good printability and cell viability. However, finding optimal process parameters is always essential for the researcher. The biological, mechanical, and rheological parameters all together need to be evaluated to enhance the printability of tissue. A degree of simplicity may be required to interpret each parameter's effect. However, overcoming complexity with a multiparameter is quite tricky through conventional methods. It can be overcome with the implementation of machine learning. This article concisely delineates the application of machine learning algorithms for modeling printability as a function of influential parameters was elaborately discussed. Additionally, indispensable challenges and futuristic aspects were briefed concerning tissue regeneration applications.

Among the possible ionic crosslinkers Ca2+ is the most widely used. However, due to its numerous physiological functions, other cations such as Sr2+ may be more suitable depending on the application. Because a systematic comparison is currently lacking, this work aims to compare solutions of CaCl2 and SrCl2 as ionic crosslinkers of alginate- and cellulose-based materials and to investigate their effects on the structural and biological properties of 3D bioprinted scaffolds. In particular, swelling and degradation under cell culture conditions, mechanical properties (with quasi-static compression tests), surface topology (with scanning electron microscopy and atomic force microscopy) and elemental composition were investigated. In addition, cytotoxicity on pancreatic islet cells was assessed by measuring viability, metabolic activity and morphology. The obtained results show that Sr2+-crosslinked scaffolds have higher compressive strength, swell faster and degrade more slowly under cell culture conditions and have a rougher surface. Both crosslinking agents were gentle on the cells, either when directly embedded into scaffolds or in contact with scaffold extracts, and allowed stable culture for 30 days. However, Sr2+-crosslinked scaffolds elicited higher metabolic activity. Overall, Sr2+ are a viable crosslinking alternative to Ca2+ and allow expanding the range of scaffold properties by adjusting the concentration or ratio in a mixed solution.

In this study, we optimized the melt polycondensation of 10-hydroxy-2-decenoic acid (10-HDA) to produce poly(10-hydroxy-2-decenoate) (PHDA) and used it to form crosslinked polyester films of PHDA via thermal- or photocuring. The physical properties of PHDA depended greatly on the polymerization conditions, particularly the temperature. The reaction conditions were optimized to achieve polymers with high weight- and number-average molecular weights of 4.182 × 104 (±0.324%) and 1.588 × 104 (±1.737%) Da. Structural, thermomechanical, and mechanical characterization revealed that the crosslinked polyester films exhibited comparable tensile properties to existing biobased plastics, with a maximum tensile strength of 29.3 MPa and an elongation at break of 331.0%. The films also demonstrated excellent thermal stability, making PHDA a promising alternative to traditional petrochemically derived polymers.

From its physicochemical characteristics, graphene oxide (GO) is a promising versatile next generation membrane material. Its unique characteristics like ultrafast permeation and hydrophilicity makes it a favourable separation membrane nanomaterial in water purification. However, a fundamental problem in the use of GO in nanofiltration is decreased performance overtime due to the pore size widening phenomenon. This paper explored the use of an amine group containing compound, 1,3,5 triazine, 2,4,6 triamine (melamine) to covalently interlink the GO nanosheets to counteract this swelling phenomenon. Prior to membrane fabrication, covalent interactions between GO and the crosslinker, melamine were successfully confirmed through thermogravimetric analysis (TGA), x-ray photoelectron spectroscopy (XPS), X-ray Diffraction (XRD) and Fourier Transform Infra-Red (FTIR) spectroscopy characterisations. Following these characterisations, crosslinked membranes were successfully fabricated and enhanced nanofiltration performance was confirmed. Resultantly, the surface morphology of the membranes was recorded via Scanning Electron Microscopy (SEM) characterisations while a lab-scale nanofiltration device was constructed for flux and rejection analysis. Evidently, performance improvement with covalent crosslinking was imminent as an up to a 100% rejection of methylene blue was achieved for the crosslinked membranes. Structural integrity of GO membranes has indeed been improved through crosslinking.

Synthetic materials cause considerable damage over long-term usage. Therefore, the multiple benefits of naturally-derived polymers are being acknowledged for sustainable material fabrication. We prepared hybrid hydrogel sheets of polysaccharides, sacran and nanocellulose as soothing wound dressings. Antibacterial activity was purveyed by introducing silver nanoparticles in the polysaccharide blend; it was further dried to a film and subsequently crosslinked via thermal annealing. This step provided physical-crosslink junctions in the matrix and firm lodging of the nanoparticles. At the same time, use of harmful chemicals was circumvented. The silver nanoparticle–polysaccharide hydrogels significantly reduce the viability of different bacteria and can potentially be applied as on-demand dressings.

The rheological and mechanical properties of elastomers are defined by their different networks: The crosslink network and the filler network. The crosslink network is influenced by the polymer structure. The filler network – particularly in case of silica as filler – depends on the interaction between the filler particles and the polymer. Liquid polymers can affect these networks by their lower molecular weight and with certain types by their functional groups. The goal of the present work is to gain a better understanding of the network formation: 1. During the sulfur curing of pure liquid polybutadienes with different concentrations of sulfur and curatives, and 2. Through differently added liquid polymer-silica-masterbatches in sulfur cured silica/SSBR mixtures. For the first point, the pre-cured liquid polymer samples were analyzed by gel permeation chromatography. The results indicate an association between weight concentration and the polymer chain length. For the second point, stress-strain analysis according to Mooney-Rivlin provides information about the interaction of liquid polymers with silica and the main polymer when it is added differently throughout the masterbatch approach.

Polymer dielectric materials operating at high temperatures are widely needed for advanced electrical and electronic systems. However, currently commercial polymer dielectrics are limited to relatively low operating temperatures. Here, a series of polyether ether ketone (PEEK)-based blends with self-crosslinkable polyetherimide (c-PEI) has been prepared as high temperature dielectrics by melt blending. The obtained polymer blends maintain stable dielectric properties over a wide frequency and temperature range. At 160 °C，the dissipation factor of the blend film is only 0.0019 which is only 14% of the pristine PEEK. Crosslinked networks in polymer blends could efficiently restrict the movement of polymer segments which suppress the dielectric loss and enhance high temperature performance. Furthermore, the introducing of Al2O3 improve the dielectric constant of the polymer blend, which compensated for the decreased dielectric constant due to crosslinking. In addition, the c-PEI/PEEK blends could be produced by industrial-grade continuous production process. This work presents a feasible strategy to large-scale fabrication of high-temperature dielectric materials by melt blending with self-crosslinkable polymers.

Both high-cycle fatigue life and fatigue crack propagation resistance of human cortical bone allograft are radiation dose-dependent between 0 and 25 kGy such that higher doses exhibit progressively shorter lifetimes. Recently, we have shown that collagen chain fragmentation and stable crosslink accumulation may contribute to the radiation dose-dependent loss in fatigue crack propagation resistance of human cortical bone. To our knowledge, the influence of these mechanisms on high-cycle fatigue life of cortical bone have not been established. Sequential irradiation has also been shown to mitigate the loss of fatigue life of tendons, however, whether this mitigates losses in fatigue life of cortical bone has not been explored. Our objectives were to evaluate the influence of radiation-induced collagen chain fragmentation and crosslinking on the high-cycle fatigue life of cortical bone in the dose range of 0-15 kGy, and to evaluate the capability of sequential irradiation at 15 kGy to mitigate the loss of high-cycle fatigue life and radiation-induced collagen damage. High-cycle fatigue life specimens from four male donor femoral pairs were divided into 5 treatment groups (0 kGy, 5 kGy, 10 kGy, 15 kGy, and 15 kGy sequentially irradiated) and subjected to high-cycle fatigue life testing with a custom rotating-bending apparatus at a cyclic stress of 35 MPa. Following fatigue testing, collagen was isolated from fatigue specimens, and collagen chain fragmentation and crosslink accumulation were quantified using SDS-PAGE and a fluorometric assay, respectively. Both collagen chain fragmentation (p = 0.006) and non-enzymatic crosslinking (p < 0.001) influenced high-cycle fatigue life, which decreased with increasing radiation dose from 0 to 15 kGy (p = 0.016). Sequential irradiation at 15 kGy did not offer any mitigation in high-cycle fatigue life (p = 0.93), collagen chain fragmentation (p = 0.99), or non-enzymatic crosslinking (p ≥ 0.10) compared to a single radiation dose of 15 kGy. Taken together with our previous findings on the influence of collagen damage on fatigue crack propagation resistance, collagen chain fragmentation and crosslink accumulation both contribute to radiation-induced losses in notched and unnotched fatigue life of cortical bone. To maximize the functional lifetime of radiation sterilized structural cortical bone allografts, pathways other than sequential radiation should be explored to mitigate collagen matrix damage., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Dylan Crocker reports financial support was provided by National Institute of Arthritis and Musculoskeletal and Skin Diseases. Megan Oest reports financial support was provided by National Institute of Arthritis and Musculoskeletal and Skin Diseases. Clare Rimnac reports financial support was provided by Musculoskeletal Transplant Foundation Inc. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The feasibility and technical capacity for producing crosslinked sub-micron gels with a nano spray-dryer were studied with variable pH systems incorporating alginate, pectin, and pullulan. The obtained powders were characterized for their morphology, particle size distribution, and their toxicological safety profile using genotoxicity and cytotoxicity assays. Additionally, quercetin was added to the encapsulation system to study the potential of the system to encapsulate this material. The produced powders exhibited morphologies and particle size distributions characteristic for nano spray-drying. The addition of pullulan and pectin to the feed solutions resulted in a particle size increase, with crosslinked alginate particles having a mean value of 1.43 μm, while particles with added pectin and pullulan had a mean particle size of 1.70 and 1.75 μm, respectively. The inclusion of quercetin proved to be problematic with this encapsulation system. Extremely high degradation rates and extremely low encapsulation efficiencies were observed due to the alkaline pH (~10) of the system that is needed to keep the feed dispersion in a liquid state and prevent premature crosslinking of the alginate. Although pectin and pullulan provided some protection for quercetin in the alkaline dispersion, the absolute quercetin content in the final product remained very low, with a maximum achieved encapsulation efficiency of 2.06 %. The safety profile of most produced powders was favourable, as they did not exhibit any significant cytotoxic and genotoxic activity in the HepG2 cell line, except in the case of Alginate/Pullulan which showed a 43 % decrease in cell viability at 500 μg/mL. Samples where quercetin was added did not show any increased toxicological effect., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

A recent elegant cryo-electron tomography study of the populations of different GroEL-GroES chaperonins complexes in whole bacterial cells (Wagner, Carvajal et al. 2024) contributes to the resolution of a long-standing debate about their mechanism, and reconciles three-decade-old results from in vitro biochemical studies, with new, refined in situ observations. Biochemists working with purified proteins often wonder if their findings faithfully reflect the situation in the crowded environment of cells, when their proteins mingle with concentrated metabolites and bump into membranes and thousands of different unrelated proteins. Here, cryo-electron tomography confirmed that careful in vitro protein biochemistry research still has a bright future., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

The fructosan levan was synthesized in vitro using a recombinant levansucrase. The levan was oxidized with sodium periodate to prepare oxidized levan (OLevan) with three oxidation degrees. OLevan, gelatin (Gel), and gallic acid (GA) were used to prepare the composite films by the method of plate pouring. The analytical results of FT-IR and XPS indicated that OLevan and gelatin were covalently crosslinked through a Schiff base reaction. The crosslinked films had better properties compared to the non-crosslinked films, especially the Gel/GA/50%OLevan film. The film had the lowest swelling degree (44.4 %), while that of Gel/GA/Levan film was 352.6 %. Gel/GA/50%OLevan film also had the highest tensile strength (25.48 MPa), while that of Gel/GA film was 9.48 MPa. Also, Gel/GA/50%OLevan film was used as a packaging material of Mozzarella cheese. The film effectively slowed down changes in the texture and color of the cheese. On the first day, the coliform in the control and PE groups had already exceeded the maximum acceptable limit of cheese (2.0 Log CFU/g). However, that of Gel/GA/50%OLevan group reached the limit on the fifth day. The results show that the new film prepared by crosslinking and composite of natural edible materials has good potential as a safe food packaging material., Competing Interests: Declaration of competing interest The authors declared that they have no conflicts of interest to this work. We declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted., (Copyright © 2024. Published by Elsevier B.V.)

Bioprinted hydrogels are extensively studied to provide an artificial matrix for 3D cell culture. The success of bioprinting hydrogels relies on fine-tuning their rheology and composition to achieve shear-thinning behavior. However, a challenge arises from the limited viscoelastic and stiffness range accessible from a single hydrogel formulation. Nevertheless, hydrogel mechanical properties are recognized as essential cues influencing cell phenotype, migration, and differentiation. Thus, it is crucial to develop a system to easily modulate bioprinted hydrogels' mechanical behaviors. In this work, we modulated the viscoelastic properties and stiffness of bioprinted hydrogels composed of fibrinogen, alginate, and gelatin by tuning the crosslinking bath solution. Various concentrations of calcium ionically crosslinked alginate, while transglutaminase crosslinked gelatin. Subsequently, we characterized the mechanical behavior of our bioprinted hydrogels from the nanoscale to the macroscale. This approach enabled the production of diverse bioprinted constructs, either with similar elastic behavior but different elastic moduli or with similar elastic moduli but different viscoelastic behavior from the same hydrogel formulation. Culturing fibroblasts in the hydrogels for 33 days revealed a preference for cell growth and matrix secretion in the viscoelastic hydrogels. This work demonstrates the suitability of the method to decouple the effects of material mechanical from biochemical composition cues on 3D cultured cells., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The increasing presence of uranium as a radionuclide contaminant in water is a threat to human health and the environment. Sonication-assisted crosslinking of guar gum, a biopolymer, is carried out with zirconium phosphate to form an adsorbent (GG@ZrP) for the removal of uranium from water. The surface characteristics, functionalities, and thermal stability of the composite were established using various analytical and spectral tools. Langmuir, Freundlich, and Sips models were used to evaluate the batch adsorption parameters. The adsorbent exhibited an excellent Langmuir adsorption capacity of 500 mg g -1 towards adsorption of uranium at pH 6. The adsorption was endothermic (ΔH, 22.63 kJ mol -1 ) and followed pseudo-second order kinetics. The synergistic influence of hydroxyl-rich guar gum and phosphate moieties resulted in efficient binding of uranium. With a high selectivity towards interfering cations and anions and applicability over a good range of pH, this adsorbent is a promising candidate for uranium remediation from water., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

There is an abrupt increase in the multiscale mechanical properties and load-bearing capabilities of tendon during development. While prior work has identified numerous changes that occur within the collagenous structure during this developmental period, the primary structural elements that give rise to this abrupt increase in mechanical functionality, and their mechanobiological sensitivity, remain unclear. To address this knowledge gap, we used a shear lag model along with ultrastructural imaging, biochemical/thermodynamic assays, and multiscale mechanical testing to investigate the dynamic structure-function relationships during late-stage embryonic chick development and to establish their sensitivity to mechanical stimulation. Mechanical testing and modeling suggested that the rapid increase in multiscale mechanics can be explained by increases in fibril length, intrafibrillar crosslinking, and fibril area fraction. To partially test this, we inhibited collagen crosslinking during development and observed a drastic reduction in multiscale mechanical behavior that was explained by a reduction in both fibril modulus and length. Using muscle paralysis to investigate mechanosensitivity, we observed a significantly impaired multiscale mechanical response despite minimal changes in fibril diameter and fibril area fraction. Additionally, the shear lag model found a trend toward lower fibril lengths with paralysis and experimental data found decreased crosslinking and fibril modulus values following flaccid paralysis. Together, these data suggest that both intrafibrillar crosslink formation and fibril elongation are critical to the formation of load-bearing capabilities in tenogenesis and are sensitive to mechanical loading. These findings provide critical insights into the biological and structural mechanisms that give rise to tensile load-bearing soft tissue. STATEMENT OF SIGNIFICANCE: Despite prior work investigating the structural and mechanical changes that occur during tendon development, there has not been a comprehensive analysis of how these simultaneous changes in structure and function are connected. In this study, we performed a comprehensive battery of mechanical and structural assessments of embryonic chick tendons and input these data into a shear lag model to estimate the individual importance of each structural change to the tendon mechanical properties. Additionally, we inhibited muscle activity in the embryos to evaluate the impact of mechanical stimulation on these evolving structure-function relationships during tendon development. These data provide insight into the primary structural elements that produce the tensile load-bearing capabilities of tendon, which will inform efforts to produce tissue engineered tendon replacements., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Aquaporin-0 (AQP0) constitutes 50 % of the lens membrane proteome and plays important roles in lens fiber cell adhesion, water permeability, and lens transparency. Previous work has shown that specific proteins, such as calmodulin (CaM), interact with AQP0 to modulate its water permeability; however, these studies often used AQP0 peptides, rather than full-length protein, to probe these interactions. Furthermore, the specific regions of interaction of several known AQP0 interacting partners, i.e. αA and αB-crystallins, and phakinin (CP49) remain unknown. The purpose of this study was to use crosslinking mass spectrometry (XL-MS) to identify interacting proteins with full-length AQP0 in crude lens cortical membrane fractions and to determine the specific protein regions of interaction. Our results demonstrate, for the first time, that the AQP0 N-terminus can engage in protein interactions. Specific regions of interaction are elucidated for several AQP0 interacting partners including phakinin, α-crystallin, connexin-46, and connexin-50. In addition, two new interacting partners, vimentin and connexin-46, were identified., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Kevin L. Schey reports financial support was provided by National Institutes of Health. Carla O'Neale reports financial support was provided by National Institutes of Health. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

In recent years, polymeric hydrogels have been employed to investigate cancer cell-extracellular matrix (ECM) interactions in vitro. In the context of breast cancer, cancer cells are known to degrade the ECM using matrix-metalloproteinases (MMPs) to support invasion resulting in disease progression. Polymeric hydrogels incorporating MMP-cleavable peptides have been employed to study cancer cell invasion, however, the approaches employed to incorporate these peptides often change other hydrogel properties. This underscores the need for decoupling hydrogel properties while incorporating MMP-cleavable peptides. Herein, we report structurally decoupled hyaluronic acid (HA) hydrogels formulated using varying ratios of a biologically sensitive MMP-cleavable peptide and an insensitive counterpart (Dithiothreitol (DTT) or polyethylene glycol dithiol (PEGDT)) to study MMP-mediated metastatic breast cancer cell invasion. Rheological, swelling ratio, estimated mesh size, and permeability measurements showed similar mechanical and physical properties for hydrogels crosslinked with different DTT (or PEGDT)/MMP ratios. However, their degradation rate in the presence of collagenase correlated with the ratio of MMP-cleavable peptide. Encapsulated metastatic breast cancer spheroids in HA hydrogels with MMP sensitivity exhibited increased invasiveness compared to those without MMP sensitivity after 14 days of culture. Overall, such structurally decoupled HA hydrogels provide a platform to study MMP-mediated breast cancer cell invasion in vitro., Competing Interests: Declaration of competing interest The authors declare that they have no conflicts of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The inferior hydrophobicity and mechanical properties of starch-based nanofibrous films significantly restrict their practical application. In view of this, this study prepared octenylsuccinylated starch-pullulan nanofibrous films using electrospinning and glutaraldehyde (GTA) gas-phase crosslinking. After GTA crosslinking, the starch-based nanofibrous films remained white, randomly oriented, smooth, and droplet-free. As the crosslinking time increased from 0 h to 24 h, the mean fibrous diameter augmented from 157.34 nm to 238.66 nm, and the water contact angle rose from 24.30° to 52.49°. Meanwhile, their tensile strength and thermal stability grew, and the mean pore area and elongation at break abated with changes in function groups. The crosslinked starch-based nanofibrous films exhibited an enhanced adsorption capacity for alcohols, ethers, esters, hydrocarbons, and N-compounds of oyster peptides. Correlation analysis shows that the adsorption capacity of the starch-based nanofibrous films was positively correlated with mean fibrous diameter and water contact angle and negatively correlated with mean pore area. These results provide a theoretical basis for the practical application of crosslinked starch-based nanofibrous film materials in deodorization., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Aiming to contribute to the current knowledge on the impact of reaction conditions on the chemical structure and target properties of starch citrates, in the current contribution different corn starch citrates were prepared by manipulation of reaction time, temperature and citric acid concentration. Modified starches were characterized in terms of chemical structure, morphology, crystallinity, swelling power and resistant starch content. For the first time, total substitution, crosslinking and monosubstitution degrees were quantitatively determined; and the relationship among final chemical structure, reaction conditions and target starch citrates properties was comprehensively analyzed. Products with total substitution values in the range of 0.075-0.24, crosslinking degrees in the 0.005-0.11 interval, and monosubstitution extents within the 0.05-0.12 range, were produced. By proper selection of reaction conditions products with almost 100 % of resistant starch were obtained. Results evidenced that starch citrates properties (mainly swelling power and RS content) depend on both chemical structure and the reaction conditions employed. Actually, the reaction temperature set (120 °C or 150 °C) proved to play a determinant role in the final products properties as evidenced from starch citrates with similar chemical structure and substantially different swelling and digestibility properties., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Galactooligosaccharides (GOS), as mimics of human milk oligosaccharides, are important prebiotics for modulating the ecological balance of intestinal microbiota. A novel carrier-free cell immobilization method was established using genipin to cross-link Kluyveromyces lactis CGMCC 2.1494, which produced β-galactosidase, an enzyme essential for GOS synthesis. The resulting immobilized cells were characterized as stable by thermogravimetric analysis and confirmed to be crosslinked through scanning electron microscopy analysis (SEM) and Fourier transform infrared spectroscopy (FTIR). The K m and V max values of β-galactosidase in immobilized cells towards o-nitrophenyl β-D-galactoside were determined to be 3.446 mM and 2210 μmol min -1  g -1 , respectively. The enzyme in the immobilized showed higher thermal and organic solvent tolerance compared to that in free cells. The immobilized cells were subsequently employed for GOS synthesis using plant-derived galactose as the substrate. The synthetic reaction conditions were optimized through both single-factor experiments and response surface methodology, resulting in a high yield of 49.1 %. Moreover, the immobilized cells showed good reusability and could be reused for at least 20 batches of GOS synthesis, with the enzyme activity remaining above 70 % at 35 °C., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Research of the nontraditional polysaccharide gellan gum (GG) is a growing space for the development of novel drug delivery systems due to its tunable physic-mechanical properties, biocompatibility, and stability in a wide range of environments. Unfortunately, high temperature crosslinking is often required, representing a limiting factor for the incorporation of thermosensitive therapeutic agents. Here, we demonstrated that GG can be crosslinked at a low temperature (38 °C) using a simple fabrication process that utilizes trilysine as an alternative to traditional mono- or divalent ion crosslinkers. While elevated temperature mixing is still required to form a clear GG solution, crosslinking of 0.5 - 1 % GG (w/v) in the presence of trilysine (0.03 % - 0.05 % w/v) was achieved at 38 °C resulting in hydrogels with suitable working formulations to facilitate syringe loading. Low injection forces (< 20 N), and biocompatibility was evaluated with normal human dermal fibroblast (cell viability > 90 %). Frequency sweep showed a transition from purely liquid-like behavior to gel-like behavior with increased trilysine concentration. A temperature dependent behavior was lost with higher trilysine concentrations, indicating stable hydrogel formation. NMR results suggest that trilysine participates in gelation via both ionic interactions between the primary amines of trilysine and the carboxylate residues of glucuronic acid and hydrogen bonding. Released studies showed that GG hydrogels can entrap and provide sustained release of IgG in relation to the crosslinker, and antibody concentration used, with a burst release within the first 24 h (∼80 % cumulative released) followed by a sustained released for up to 5 days. Overall, findings demonstrate a promising nontoxic injectable hydrogel that requires lower crosslinking temperatures, is simple to manufacture and serves as a carrier of thermosensitive therapeutic agents., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Jeannine M. Coburn reports financial support was provided by Worcester Polytechnic Institute. Carolina Villarreal-Otalvaro reports a relationship with Boston Scientific Corporation that includes: employment. Joseph T. Delaney reports a relationship with Boston Scientific Corporation that includes: employment. Rick W. Dorn reports a relationship with Boston Scientific Corporation that includes: employment. Bhanu Koppolu reports a relationship with Boston Scientific Corporation that includes: employment. Carolina Villarreal-Otalvaro has patent #Therapeutic Hydrogels (US2022/0313603 A1) pending to Boston Scientific Corporation. Bhanu P. Koppolu has patent #Therapeutic Hydrogels (US2022/0313603 A1) pending to Boston Scientific Corporation. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Wound dressings play a crucial role in protecting injured tissues and promoting the healing process. Traditional fabrication of antibacterial wound dressings can be complex and may involve toxic components. In this study, we developed an innovative hydrogel film (AP:GE@OTA/Ag) composed of amidated pectin (AP), gelatin (GE), oxidized tannic acid (OTA) at varying concentrations, and in-situ reduced silver nanoparticles (AgNPs). FTIR and XRD analyses confirmed that crosslinking occurs via interactions between OTA quinone groups and free amino groups in AP and GE. TEM imaging demonstrated the well-dispersed AgNPs with an average particle size of 58.64 nm, while the TG measurements indicated the enhancement of the thermal stability compared to AP:GE films. The AP:GE@OTA/Ag films exhibited superior fluid uptake ability (90.96 % at 2 h), water retention capacity (91.69 % at 2 h), and water vapor transmission rate (1903.29 g/m 2 /day), alongside improved tensile strength (38 MPa). Additionally, these films showed excellent cytocompatibility and sustained potent antimicrobial activity against S. aureus and E. coli with low AgNPs loadings of 1.02 ± 0.13 μg/cm 2 . NIT-1 mouse insulinoma cells demonstrated robust proliferation when cultured with the prepared dressings. These films significantly accelerated wound repair in a skin excision model, indicating their potential clinical applications for wound healing., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

This study focused on preparing biodegradable dual-layered mulch film based on polyhydroxyalkanoate (PHA) and polycaprolactone (PCL). The main aim of this study is to prepare mulch film with higher biodegradability for rice seed germination. Common plastic mulch films are mostly non-readily biodegradable and stay as residual in soil for a very long duration leading to an increase in salt content and reduction in water and nutrient movement in the soil. This makes the farmland unusable for agricultural purposes. The PHA and PCL were the ideal options as both have their merits and demerits which compensates each other while being cast into double layers and are highly biodegradable. The novelty of this study emphasizes the attachment of PHA and PCL as a dual layer at different ratios that offers a higher bio-degradability percentage. The dual-layer mulch film is made of PHA as the first layer and a mixture of PHA and PCL at different ratios as the second layer. The ratio of PHA/PCL used was 90:10, 70:30, and 50:50. The dual-layered mulch film was prepared using the hot-press technique and later cross-linked by using electron beam irradiation in order to ensure the strong adherence between the two layers. The gel content analysis was performed to measure the crosslinking percentage. The radiation dose of 30 kGy was chosen as the minimum amount of crosslinking and approximately 3.00% was attained for the course. The mixture of PHA/PCL films with different ratios, PHA and PCL virgin film were subjected to a soil burial bio-degradability test. The PHA and PCL virgin film had shown the highest degradation percentage, almost 48.34% just in five weeks. Further characterization was performed on virgin dual-layered PHA/PCL (100%) based on their higher degradability tendency. The apparent properties, morphology, thermal stability, chemical composition, and mechanical properties of dual-layer PHA/PCL (100%) were tested thoroughly. The thickness and transparency attained for dual-layer PHA/PCL (100%) were around 175.25μm and 110.45%. The thermal properties of both single layer PHA and PCL showed good stability, Meanwhile, the virgin dual-layered PHA/PCL mulch film had shown a poor thermal stability. The peak positioning in FTIR for single layer PHA and PCL at 3042.37cm−1, 2942.37cm−1, 1719.54cm−1,1453.33cm−1,1378.95cm−1 and 1181.48cm−1 remained unchanged in virgin double-layered PHA/PCL film as well. The outcome of the analyses clearly indicates the possibilities of the dual-layer PHA/PCL (100%) with greater bio-degradability. The soil burial biodegradability test needs to be prolonged up to its full potential. The other characteristics such as water permeability, photo permeability, crystallinity, and heat preservation need to be investigated as well.

Purpose: To report two cases of acute corneal melting and perforation requiring emergency penetrating keratoplasty after corneal crosslinking (CXL) in advanced keratoconus. Observations: Case 1 was a 34 and case 2 was a 16-year old male, both with progressive keratoconus, who underwent CXL (Dresden protocol). After riboflavin imbibition, patients had a minimal pachymetry of 337 μm and 347 μm, and therefore required stromal swelling by hypoosmolar riboflavin resulting in pachymetries of 470 μm and 422 μm, prior to the 30 minute UV-irradiation with 3mW/cm2. In case 1, on the 7th postoperative day a 4mm linear perforation occurred. Extensive post-hoc examinations revealed no infectious cause. In case 2, a corneal melting developed within 24 hours, from which Staphylococcus aureus was cultured. Conclusions and importance: Acute corneal melting and perforation may occur after CXL. Dysfunctional collagen metabolism, atopia, thin preoperative pachymetry and the use of hypoosmolar substances may have initiated this complication in our cases.

Keeping in view the therapeutic and gel forming role of the psyllium seed mucilage in pharmaceutical industries, herein this article, its potential has been explored for developing the drug delivery (DD) carrier. The main aim of the study was to modify the psyllium polysaccharides through grafting and crosslinking of 2-methacryloyloxyethyl trimethylammonium chloride onto psyllium to develop the hydrogels for use in DD application. Various thermal, mechanical, physiochemical, biomedical properties of the hydrogel were determined along with characterization with 13C NMR, FTIR, XRD, TGA, DSC and AFM. The release of antibiotic drug cefuroxime occurred in sustained manner and followed Fickian diffusion mechanism and was best fitted in Higuchi kinetic model. The networks showed mesh size in the range between 25.14 to 38.92 nm during the change in crosslinker content in copolymerization reaction. It has been inferred from the results that these hydrogels could be used as a potential carrier for drug delivery.

Hydrogels are commonly used in wound dressing, as they retain moisture, accelerate healing, and break down necrotic tissue. This process enhances patient comfort levels while simultaneously reducing pain caused by dead tissue. The purpose of this study was to investigate the in vivo toxicity of a dual hydrogel consisting of type I atelocollagen cross-linked with sodium hyaluronate hydrogel used for wound dressing.Porcine type I atelocollagen was cross-linked with sodium hyaluronate to form the hydrogel. For subcutaneous implantation, 0.5 ml of dual hydrogel was injected into two different sites of twenty rats per group. High density polyethylene rods were implanted subcutaneously to serve as a control material. Hematological assessment, blood biochemistry, histopathological, and histological evaluations were scored and graded after 4 weeks. A bioreactivity rating was used for evaluation of subacute toxicity.Differences observed in blood chemical analysis and hematological analysis between control and test groups were within normal variations and considered unrelated to the test article implantation. No significant implantation-related lesions were observed in any of the major organs of all test animals. The overall histopathological index of the test article implantation sites was evaluated as 0. The bioreactivity rating was evaluated as non-irritant after 4-week subcutaneous implantation.Overall, these results indicate that the dual hydrogel of type I atelocollagen and sodium hyaluronate is biologically and chemically safe for clinical application as a wound dressing.

Rubber is well known as the basic material for some structural devices, such as seaport fenders and seismic isolators. In practice, to seismically isolate a structure it is necessary to interpose between the foundation and the superstructure a rubber device that increases the period of the superstructure, a feature that allows the structure to be ''transparent'' to the seismic excitation. A seismic isolator is constituted typically by a package of several rubber pads 1–2 cm thick vertically interspersed with either steel laminas or FRP dry textiles suitably treated. In this latter case the isolator is called FREI (Fiber Reinforced Elastomeric Isolator). FREIs exhibit light weight, easy installation and low cost. In this study, recycled rubber in the form of reactivated EPDM has been used to produce very low cost FREIs, combined with glass fiber reinforcement. To be ready for structural application, the rubber used must be vulcanized correctly to properly create the polymer crosslinking. However, all rubber mechanical properties are strongly affected by curing temperature and curing time. Here, the mechanical properties of a typology of FREI conceived and produced by the authors in prototypes are evaluated through a series of experimental tests and numerical computations, taking into account the different levels of vulcanization degree. Shore A hardness test, uniaxial tensile test, and relaxation test have been conducted and verified through Finite Element (FE) modeling. All collected data allow to precisely determine the curing time and temperature to use in the industrial production to obtain optimal output mechanical properties for FREIs.

Mechanical interactions between cells and the extracellular matrix (ECM) lead to the formation of biophysical cues, notably in the form of cell-generated tension, stiffness, and concentration profiles in the ECM. Fibrillar ECMs have nonlinear stiffnesses, linked to the reorientation of fibers under stress and strain, and nonelastic properties, resulting from the force-induced unbinding of transient bonds (crosslinks) that interconnect fibers. Mechanical forces generated by cells can lead to local ECM stiffening and densification. Cell tension is also propagated through the ECM network. The underlying factors that regulate the relative emergence of these signals are not well understood. Here, through computational simulations of 3D ECM fiber networks, we show that the composition of ECM crosslinks is a key determinant of the degree of densification and stiffening that can be achieved by cell-generated forces. This also regulates the sustainability of tensions propagated through the ECM. In particular, highly transient force-sensitive crosslinks promote nonelastic densification and rapid tension relaxation, whereas permanent crosslinks promote nonlinear stiffening and stable tension profiles. A heterogeneous population of crosslinks with different unbinding kinetics enables ECMs to exhibit accumulation, tension propagation, and stiffening simultaneously in response to mechanical interactions with cells.

Purpose: To describe a case of recalcitrant Acanthamoeba Keratitis (AK) complicated by medical non-compliance and medication intolerance that was successfully treated with photoactivated chromophore for infectious keratitis corneal collagen cross-linking (PACK-CXL). Observations: A 31-year-old male presented with right eye pain and redness in the setting of fresh water exposure and scleral contact lens wear. He had lack of a response to treatment with antiviral therapy for 3 months by an outside provider. Cultures were found to be positive for Acanthamoeba and the patient was treated with an extended course of various anti-amoebic therapies with poor compliance due to pain and toxicity. He was eventually treated with intrastromal voriconazole and Miltefosine without improvement and eventually had PACK-CXL with resolution of his infection and pain. Conclusion: PACK-CXL was associated with a dramatic improvement in a case of recalcitrant Acanthamoeba keratitis unresponsive to both traditional and novel therapies and may be a viable alternative or adjunctive therapy for Acanthamoeba keratitis.

Abstract Background In the fibrin‐forming process, thrombin cleaves fibrinogen to fibrin, which form fibrils and then fibers, producing a gel‐like clot. Thrombin also activates coagulation factor XIII (FXIII), which crosslinks fibrin γ‐chains and α‐chains, stabilizing the clot. Many proteins bind to fibrin, including FXIII, an established regulation of clot structure, and platelet glycoprotein VI (GPVI), whose contribution to clot function is largely unknown. FXIII is present in plasma, but the abundant FXIII in platelet cytosol becomes exposed to the surface of strongly activated platelets. Objectives We determined if GPVI interacts with FXIII and how this might modulate clot formation. Methods We measured interactions between recombinant proteins of the GPVI extracellular domain: GPVI‐dimer (GPVI‐Fc2) or monomer (GPVIex) and FXIII proteins (nonactivated and thrombin‐activated FXIII, FXIII subunits A and B) by ELISA. Binding to fibrin clots and fibrin γ‐chain crosslinking were analyzed by immunoblotting. Results GPVI‐dimer, but not GPVI‐monomer, bound to FXIII. GPVI‐dimer selectively bound to the FXIII A‐subunit, but not to the B‐subunit, an interaction that was decreased or abrogated by the GPVI‐dimer–specific antibody mFab‐F. The GPVI‐dimer–FXIII interaction decreased the extent of γ‐chain crosslinking, indicating a role in the regulation of clot formation. Conclusions This is the first report of the specific interaction between GPVI‐dimer and the A‐subunit of FXIII, as determined in an in vitro system with defined components. GPVI‐dimer–FXIII binding was inhibitory toward FXIII‐catalyzed crosslinking of fibrin γ‐chains in fibrin clots. This raises the possibility that GPVI‐dimer may negatively modulate fibrin crosslinking induced by FXIII, lessening clot stability.

Pollution owing to the dye house wastewater and negligent disposal of proteinaceous wastes are major threats to the environment. The conventional water treatment and solid waste management techniques are neither efficient nor cost effective. Here, we developed a collagen-TiO2 nanoparticles based photocatalytic nanobio-sponge from bio-waste for the remediation of organic dyes from wastewater. TiO2 nanoparticles were functionalized (TIF) with 3-aminopropyltriethoxysilane for stabilizing type-I collagen fibers extracted from cowhide wastes. 13C-nuclear magnetic resonance (13C NMR) and Fourier-transform infrared (FT-IR) spectroscopic analyses confirm the amine functionalization on the surface of TiO2 nanoparticles. Thermal stability of collagen fibers is increased to 84 °C after treatment with TIF, which is 20 °C higher than that of pristine collagen fibers. Further, we converted them into a bio-sponge for photocatalytic degradation of Rhodamine-B (RhB). We demonstrate that the collagen nanobio-sponge loaded with 10% (w/w) TIF nanoparticles can degrade RhB up to 95% under visible light irradiation as well as direct sunlight with a reduction in chemical oxygen demand up to 94%. Photo degradation of RhB was not manifested when the reaction was carried out in dark conditions. The results of this study pave way for the cost-effective and sustainable development of engineered biomass based sponges for real-life environmental remediation applications.

In this paper, a spotlight is shown on polysaccharides based biomaterials which have surfaced as a versatile platform for different biomedical applications including drug delivery and tissue regeneration. Herein, structure and unique properties of different polysaccharides are described along with various functionalization strategies. Additionally, a brief overview of different physical and chemical crosslinking approaches to design polysaccharides derived biomaterials is provided. Due to their inherent biocompatible and biodegradable properties, polysaccharides based biomaterials are being extensively explored for performing a difficult task under complex biological environment. Hence, recent developments in using polysaccharides derived functional biomaterials especially for drug delivery and tissue engineering applications are described here. The studies reviewed here motivate to fabricate novel polysaccharides based biomaterials with outstanding properties and functionality. Finally, various future possibilities to achieve their widespread commercial use are discussed.

Liquid polymers are used in elastomeric compounds to modify their processing and final characteristics. The material is considered as a polymeric plasticizer and is used to substitute or supplement conventional plasticizer like paraffinic or aromatic oils, or hydrocarbon resins. Their plasticizing effect and contribution to the crosslinking in sulfur cured SSBR mixtures is studied. Aromatic oil, aliphatic resin and different liquid polymers, varied in type, molecular weight and microstructure are discussed. Different plasticizing effects are shown with corresponding curing torques and Shore hardness values. The free volume – measured by positron annihilation lifetime spectroscopy - increases or decreases according to the liquid polymer's incorporation in the main polymer.

Polyvinylidene fluoride (PVDF) preferentially crosslinks upon exposure to ionizing electron beam irradiation, leading to substantial changes in its physicomechanical and thermophysical properties. However, low dose electron beam irradiation produces inefficient crosslinking in pure PVDF while high dose irradiation tends to induce the concomitant process of transverse bond degradation. This has been addressed by incorporating a sensitizer into PVDF to increase crosslinking efficiency under low dose irradiation. However, conventional sensitizers typically suffer from self-polymerization and the release of toxic volatile gases at high temperature, which diminishes the crosslinking efficiency and is toxic. This issue is addressed here via a series of well-designed bismaleimide (BMI) sensitizers and incorporating these into PVDF films for facilitating chemical crosslinking reactions under low electron beam irradiation doses. Analysis indicates that the sensitizing action of the proposed BMI sensitizers may be due to the formation of transverse bonds between vinylene groups and PVDF chains. Versus conventional triallyl isocyanurate and trimethylolpropane triacrylate sensitizers, the proposed BMI sensitizers facilitate high radiation crosslinking efficiency and exhibit good compatibility. Accordingly, the proposed sensitizers leading to irradiated PVDF films with outstanding thermomechanical performance and shape memory functionality.

The manufacture of eco-friendly cocoon silk-derived sericin films increases the availability of sericulture resources and the interest in expanding the range of the potential applications of sericin-based materials. However, the brittleness and weak tensile properties of sericin and its vulnerability to moist environments have limited its use. To overcome these two shortcomings of sericin, a functionalized bacterial cellulose-derived nanocrystal (average diameter: 25.4 nm) capable of physical strengthening and chemical crosslinking on existing sericin films was prepared. The improvement of the optical, physicochemical, and mechanical properties of the sericin film was observed through the dialdehyde bacterial cellulose nanocrystals (D-CNCs) incorporated into the silk sericin (SS) matrix. The physical reinforcing effect of the D-CNCs on the SS films enhances the mechanical properties of the films. Simultaneously, the chemical crosslinking reaction of D-CNCs develops the ultraviolet-blocking, water-resistant, and antioxidant properties of the films. The simultaneous fabrication, physical reinforcement, and chemical crosslinking of the SS/D-CNCs biocomposite film produced using an aqueous solution will provide information on the functionalization and performance improvement of water-soluble biopolymeric materials, especially hydrophilic protein resources.

The optimization of collagen-based scaffolds for tissue engineering goes through the careful selection of the crosslinking method(s), which should impart the prerequisite mechanical and degradation properties without impairing the cell/tissue response. Here, we investigated the chemically effective (ρxch) and the elastically effective (ρxel) crosslink density of collagen-based scaffolds, induced by various crosslinking methods. The aim was to get a deeper insight into the influence of intramolecular and intermolecular crosslinks on several scaffold properties. Freeze-dried collagen matrices were crosslinked via a dehydrothermal treatment (DHT), and then treated with different chemical agents, including carbodiimide (EDC), glutaraldehyde (GTA), formaldehyde (FA), genipin (GP) and dimethyl suberimidate (DMS). Quantification of primary amines and stress-relaxation compressive tests were performed to evaluate ρxch and ρxel, respectively. Scaffolds were then assessed for their water uptake, thermal stability and in vitro resistance to enzymatic degradation. Interestingly, for the various crosslinking treatments ρxch was found to increase in the order DHT

Novel positively charged nanofiltration membranes were facilely prepared by polydopamine (PDA) deposition followed by crosslinking on the polyethersulfone (PES) ultrafiltration (UF) membrane substrate. Specifically, small molecules DMAPA and 1,3-dibromopropane were separately selected as the bridge agent and crosslinking agent, which can not only realize the moderate crosslinking and densification of the loose structure of the PDA layer, but also further improve the hydrophilicity and positive charges of the PDA layer. Under the optimized conditions of DMAPA concentration (2 g/L), 1,3-dibromopropane concentration (10 wt%) and reaction time (9 h), the composite membrane had the surface pore size as low as 1.1 nm, water contact angle as low as 35.1° and zeta potential as high as +63.8 mV at pH = 6. As a result, the optimized positively charged NF membrane (M3) showed an outstanding permeance up to 15.7 L m−2 h−1 bar−1 while maintaining a high rejection above 95% for MgCl2. Meanwhile, M3 also showed good environmental adaptability when facing complex feeding or operating conditions. This work provided new situation in the design and construction of positive charged NF membranes for high efficiency cation separation.

Silane coupling agents are used in silica filled rubber compounds to increase the filer-polymer interactions and to lower the filler-filer interactions. In addition, silane functionalized polymers can be used. Special types of polymers are low molecular weight ‘liquid’ polymers. The goal of this paper is to obtain more understanding about the uses and effects of these low molecular weight ‘liquid’ polymers in combination with silanes and other compound components. Three different silane coupling agents and six different low molecular weight ‘liquid’ polymers were selected, evaluated and comparatively introduced in mixtures of a SSBR/silica compound. The Payne effect was measured to evaluate the strain dependence of the mixtures. It was used to evaluate the filler-filler interactions and estimate the micro dispersion. This provides information about the interactions and the building of additional networks that comprises the low molecular weight ‘liquid’ polymer together with the silica, silane and main polymer. Results of dynamic mechanical analysis are discussed. The microstructures and silane-functionalizations show clear dependences on the glass transition temperatures, loss moduli and tan δ values.