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• Maleic terminated PEG (PEG-MA) was synthesized without use of any catalyst. • Chitosan/PEG-MA hydrogels were fabricated using facile thermal crosslinking method. • In vitro and in vivo results showed complete biocompatibility and accelerated wound closure for hydrogels. The aim of this study was to fabricate a hydrogel based therapy to accelerate full-thickness wound healing process. Hydrogel matrix was composed from of chitosan as backbone and maleic terminated polyethylene glycol (PEG-MA) as crosslinking agent. PEG-MA was synthesized through a reaction of PEG with maleic anhydride. For hydrogel preparation, various PEG-MA/chitosan ratios were assessed to find the optimum ratio. Further improvement on hydrogel properties was achieved by adding TiO 2 nanoparticles to the matrix. PEG-MA synthesis was confirmed using 1H NMR and FTIR. Several characteristics of hydrogels, including swelling ratio, mechanical properties, water contact angle, and in vitro biocompatibility were appraised for both TiO 2 -free hydrogels and TiO 2 loaded hydrogels. Optimum hydrogels were then selected for in vivo analysis. Results indicate that hydrogels have a porous structure with swelling ratio in the range of 240–280%. In vitro estimations also revealed that hydrogels are completely biocompatible, while they could support human fibroblast cell proliferation during tested time (7 days). In vivo biocompatibility and full-thickness wound closure tests proved the biocompatibility of hydrogels in vivo and accelerated wound closure, respectively, in rat models. Overall, our findings indicate that the fabricated hydrogels are good nominates for wound healing applications as they enhance the wound contraction process with improved vascularization. [ABSTRACT FROM AUTHOR]

In this study, we have demonstrated a facile method to convert corncob, an abundant and low-cost bio-waste, into a superhydrophobic magnetic bio-sorbent with potential application in oil spill remediation. We immobilized CoFe 2 O 4 nanoparticles on the surface of corncob using the co-precipitation method to magnetize the surface of the bio-waste. Additionally, we applied silica and octadecylamine (ODA) coatings to create a rough and low surface energy sorbent material, respectively, which significantly improved its oil sorption capacity. The fabricated magnetic composite exhibited excellent magnetic responsivity (saturation magnetization: 32 emu/g), superhydrophobicity (water contact angle: 165˚), and superoleophilicity (oil contact angle: 0˚). The modified corncob (MCC) powder was easily separated using a magnetic field and showed oil sorption capacity 22.13, 13.33, 57.65, and 44.17 times its original weight for crude oils with API 23.5° and 29.7°, fresh and used motor oil, respectively. The fabricated bio-sorbent could be recovered and reused in oil-water separation at least 10 times, with a water contact angle and sorption capacity of 158.5˚ and 42 g/g, respectively, after 10 cycles. Furthermore, it displayed remarkable durability in corrosive media. We compared the performance of MCC powder with three different bio-wastes, including coconut husk, acorn, and rice husk, and found that MCC powder and coconut husk showed preferable performance over the others. Overall, our study provides a facile and efficient method for converting corncob and other bio-wastes into a superhydrophobic magnetic bio-sorbent for oil spill cleanup. [Display omitted] • Different bio-wastes including corncob, acorn shell, coconut and rice husk were used to produce recyclable magnetic sorbents. • The modified magnetic bio-sorbents exhibited excellent hydrophobicity and oleophilicity. • Fast and selective removal of oils from water surface was maintained with modified bio-wastes. • Modified corncob sorbent showed super oil remediation even after ten cycles and under corrosive environment. [ABSTRACT FROM AUTHOR]