The self-healable polymer hydrogel along with reversible temperature responsiveness was prepared through self-catalyzed dynamic acylhydrazone formation and exchange without any additional stimulus or catalyst. The hydrogel was prepared from a copolymer of N-isopropylacrylamide and acylhydrazine P(NIPAM-co-AH) cross-linked by PEO dialdehyde. Besides self-healed under catalysis of acid and aniline, the hydrogel can also self-heal activated by excess of acylhydrazine groups. Without interference of catalyst during the hydrogel formation and self-healing, this kind of hydrogel prepared from biocompatible polymers can be used in more areas including biotechnology and be more persistent. The hydrogel with a large part of the PNIPAM segment also showed temperature responsiveness around body temperature influenced by the variation in group ratio. This self-healable hydrogel has great potential application in areas related to bioscience and biotechnology.

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The biological barrier of solid tumors hinders deep penetration of nanomedicine, constraining anticancer treatment. Moreover, the inherent multidrug resistance (MDR) of cancer tissues may further limit the efficacy of anti-tumor...

There are issues and challenges in treating deep burns because of the long recovery time, frequent dressing changes, wound infection, and easy to form scar that influence aesthetics. Besides, some specific tissues are not suitable for large dressing coverage (e.g., face, perineum). Therefore, an ideal deep burn dressing should have good adhesion properties to fit the wound effectively, painless and quick replacement, resistant to infection, accelerate wound healing, reduce scarring and facilitate monitoring and diagnosis. Herein, an anti-dehydration and rapid-trigger multifunctional hydrogel dressing is prepared by interface reaction. The Pacrylamide-Formylboronicacid-Tannic acid (PAFT) hydrogels are prepared by a simple method on anti-dehydration elastomeric membrane, which is obtained using tannic acid as a dynamic crosslinking agent with 3-formylboronic acid and acrylamideunder UV light. The hydrogel exhibits a strong interfacial adhesion (892 J m −2 ± 65 J m −2 ), which rapidly (2 min) decreases (to 180 J m −2 ± 20 J m −2 ) when in the presence of glucose solution. The hydrogel has excellent anti-dehydration and moisturizing properties, and also exhibits superior antibacterial properties, hemostasis, and biocompatibility. This hydrogel is transparent allowing effective observation of wound transformation and therapeutics. Moreover, PAFT hydrogel accelerates the healing of deep burns and reduces scars.

Chitosan is a biodegradable natural polymer derived from the exoskeleton of crustaceans. Because of its biocompatibility and non-biotoxicity, chitosan is widely used in the fields of medicine and agriculture. With the latest technology and technological progress, different active functional groups can be connected by modification, surface modification, or other configurations with various physical, chemical, and biological properties. These changes can significantly expand the application range and efficacy of chitosan polymers. This paper reviews the different uses of chitosan, such as catheter bridging to repair nerve broken ends, making wound auxiliaries, as tissue engineering repair materials for bone or cartilage, or as carriers for a variety of drugs to expand the volume or slow-release and even show potential in the fight against COVID-19. In addition, it is also discussed that chitosan in agriculture can improve the growth of crops and can be used as an antioxidant coating because its natural antibacterial properties are used alone or in conjunction with a variety of endophytic bacteria and metal ions. Generally speaking, chitosan is a kind of polymer material with excellent development prospects in medicine and agriculture.