Chitin derived from seafood wastes is a sustainable biopolymer, which can be used to constructe new materials to reduce the environmental pollution caused by non-biodegradable plastics. Herein, nanofibrous microspheres fabricated from chitin solution were used as carriers to construct three different chitin-supported Pd catalysts through diverse activation methods, subsequently revealed their differences in structure and performance. The palladium nanoparticles were firmly and highly dispersed on the microspheres due to the interconnected nanofibrous networks and functional groups of chitin, confirmed by various physicochemical characterizations. As the best candidate catalyst of Pd/chitin-Ar, in the CO oxidation reaction, which achieved 100% CO conversion with a lower Pd content, and exhibited excellent stability in 24-hours cycle reaction. Importantly, the catalyst was further applied in Heck coupling reaction, which also displayed competitive catalytic activity and stability (∼6runs, 94%). Setanaxib cell line This utilizing of biomass resource to build catalyst materials would be important for the sustainable chemistry.The advent of high-performance conductive organohydrogels, which are sustainable in extremely cold environment, has attracted immersing interest in biosensors. In this work, a highly stretchable, self-healable, adhesive and antibacterial cellulose-based ionic conductive organohydrogel with low-temperature strain sensitivity was developed, using in-situ polymerization of acrylamide in glycerol-water with poly (vinyl alcohol), chitosan, FeCl3 and 2,2,6,6-Tetramethylpiperidine-1-oxyl oxidized cellulose nanofibril (TCNF). Owing to their chemically cross-linked structures and multiple H-bonding networks, the organohydrogel exhibits excellent mechanical properties, such as high stretchability (540 %), high compression strength (0.44 MPa), nearly 87 % self-healing efficiency and adhesive to various substrates. Also, good antibacterial property was confirmed by the diameter of inhibition zone (∼5.1 mm) against Salmonella enteritidis. Notably, the organohydrogels remained high conductivity and flexibility even below -20 °C, which can be applied as low-temperature strain sensor for real-time. Therefore, it has promising applications in artificial intelligence and personal healthcare under cold environment.Deep eutectic solvents (DESs), as emerging green solvents, provide a new opportunity for the biorefinement of biomass, component extraction, and cellulose nanofibrillation. Herein, different carboxylic acid-based DESs were applied for preparation of cellulose nanofibers (CNFs) from cellulose raw materials accompanied by simultaneous esterification modifications of CNFs. The results showed that pretreatment of DESs combined with mechanical treatment can swell and esterify the cellulose materials, producing CNFs with widths less than 100 nm. The DES pretreatment temperature played important roles in the esterification modifications and nanofibrillation of cellulose. The esterification modifications of cellulose prevented the over-hydrolysis and dissolution of cellulose during the DES pretreatment, guaranteeing CNFs with high yields of 72 %-88 % and maintaining the cellulose I crystal structure. Moreover, the esterified CNFs were used as a reinforcement to prepare CNF-strengthened polylactic acid (PLA) composites. The surface esterification of the CNFs improved their dispersibility and interfacial compatibility with PLA, thereby achieving the mechanical enhancement of CNF/PLA composites.The synthesis and specific surface functionalization of antimicrobial silver nanoparticles (AgNPs) and their incorporation into an alginate hydrogel is described. Divalent cation-mediated ionic crosslinking was used to disperse the AgNPs throughout the gel, made possible by -COO- cross-linking sites provided by the surface-enhanced nanoparticles, inspired by the classic egg-box model crosslinking of calcium alginate. An AgNP concentration, 10-20 μg g-1 increased hygrogel elasticity, viscosity, and shear resistance by 45, 30, and 31% respectively. Cryo-TEM revealed evenly distributed AgNP assemblies of discrete AgNPs throughout the gel matrices. FTIR-ATR indicated AgNPs were involved in alginate carboxylate-Ca2+-COO-AgNP crossbridging, which was not achieved through mixing of AgNPs into preformed gels. Live/dead fluorometric assays determined a minimal bactericidal concentration of 25 μg g-1 Ag for 6 microorganisms. Anti-biofilm assays showed species-dependent cell death of 44 -61%, with limited silver ion release of 0.41% and 1.1% after 7 days for Gram positive and negative bacteria, respectively.A simplistic synthesis approach for fabrication of ultra-light density (2.2 to 24 mg. cm-3), highly porous (98.4%-99.8%), and cross-linked natural cellulose aerogel from rice straw was developed via a freeze-drying process. The obtained natural cellulose aerogels exhibited porous network structure with specific areas of 178.8 m2. g-1 and mesopore volumes of 0.8 cm3. g-1. The cellulose aerogel with 1.3 wt% displayed the highest Young's modulus and compressive strength. Subsequent hydrophobic coating with methyltrimethoxysilane, the super-hydrophobic and oleophilic cellulose aerogel (water contact angle as high as 151 ± 7°) were capable of adsorbing a wide range of organic solvents and oils with adsorption capacities up to 170 g. g-1 based on the density of the liquids. Furthermore, the adsorbed organic solvent could be desorbed by means of simple mechanical squeezing. These results suggested that the super-hydrophobic natural cellulose aerogel can be used as a precious sorbents for adsorption of oil and organic solvents.The aim of this study was to develop a novel Kappa carrageenan (κCA)-coated Starch/cellulose nanofiber (CNF) with adjustable mechanical, physical and biological properties for hemostatic applications. Results indicated that compared to Starch/CNF hydrogel, mechanical strength of κCA-coated Starch/CNF hydrogels significantly enhanced (upon 2 times), depending on the κCA content. Noticeably, the compressive strength of Starch/CNF increased from 15 ± 3 kPa to 27 ± 2 kPa in the 1% wt. κCA coated sample. Furthermore, the surface modification of Starch/CNF hydrogel using κCA reduced swelling ability (upon 2.3 times) and degradation rate (upon 2 times). Hemolysis and clotting tests indicated that while the hybrid hydrogels were blood compatible, they did not significantly change the blood clotting ability of starch matrix. The synergistic effects of Starch/CNF hydrogel and κCA coating provided excellent properties such as superior mechanical properties, adjustable degradation rate and blood clotting ability making κCA-coated Starch/CNF hydrogel a desirable candidate for hemostatic applications.Setanaxib cell line
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