Skin wounds not only cause physical pain for patients but also are an economic burden for society. It is necessary to seek out an efficient approach to promote skin repair. Hydrogels are considered effective wound dressings. They possess many unique properties like biocompatibility, biodegradability, high water uptake and retention etc., so that they are promising candidate materials for wound healing. Chitosan is a polymeric biomaterial obtained by the deacetylation of chitin. With the properties of easy acquisition, antibacterial and hemostatic activity, and the ability to promote skin regeneration, hydrogel-like functional wound dressings (represented by chitosan and its derivatives) have received extensive attentions for their effectiveness and mechanisms in promoting skin wound repair. In this review, we extensively discussed the mechanisms with which chitosan-based functional materials promote hemostasis, anti-inflammation, proliferation of granulation in wound repair. We also provided the latest information about the applications of such materials in wound treatment. In addition, we summarized the methods to enhance the advantages and maintain the intrinsic nature of chitosan via incorporating other chemical components, active biomolecules and other substances into the hydrogels.

Medical device contamination caused by microbial pathogens such as bacteria and fungi has posed a severe threat to the patients’ health in hospitals. Due to the increasing resistance of pathogens to antibiotics, the efficacy of traditional antibiotics treatment is gradually decreasing for the infection treatment. Therefore, it is urgent to develop new antibacterial drugs to meet clinical or civilian needs. Antibacterial polymers have attracted the interests of researchers due to their unique bactericidal mechanism and excellent antibacterial effect. This article reviews the mechanism and advantages of antimicrobial polymers and the consideration for their translation. Their applications and advances in medical device surface coating were also reviewed. The information will provide a valuable reference to design and develop antibacterial devices that are resistant to pathogenic infections.

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As the implications of reactive oxygen species (ROS) are elucidated in many diseases, ROS-responsive nanoparticles are attracting great interest from researchers. In this work, a ROS sensitive thioketal (TK) moiety with a π-conjugated structure was introduced into biodegradable methoxy poly(ethylene glycol)-thioketal-poly(ε-caprolactone)mPEG-TK-PCL micelles as a linker, which was designed to speed up the drug release and thus enhance the therapeutic efficacy. The micelle showed a high drug loading content of 12.8% and excellent stability under physiological conditions because of the evocation of π-π stacking and hydrophobic interactions with the anticancer drug doxorubicin (DOX). The polymeric micelle presented a better drug carrier capacity and higher in vitro anticancer efficacy towards cancer cells. The in vivo study showed that DOX-loaded mPEG-TK-PCL micelles displayed lower toxicity towards normal cells and remarkably enhanced antitumor efficacy. This research provides a way to design potential drug carriers for efficient cancer chemotherapy.