An injectable in situ-forming hydrogel with self-activating genipin-chitosan (GpCS) cross-linking and an O/Ca self-supplying capability for wound healing and rapid hemostasis.

Severe traumatic bleeding and chronic diabetic wounds require rapid hemostasis and multifunctional dressings, which remain particularly challenging, especially for non-compressible trauma and irregular wounds with dysregulated microenvironments. Chitosan (CS) can be easily cross-linked with genipin to form GpCS hydrogels. However, developing injectable GpCS hydrogels for biomedical applications faces challenges, particularly in enhancing rapid gel formation and optimizing physical properties.

Modification of chitosan nanofibers with CuS and fucoidan for antibacterial and bone tissue engineering applications.

Chitosan (CS) electrospun nanofiber (ENF) membranes were modified with fucoidan (Fu) and CuS NPs through polyelectrolyte complexation and genipin (GP)-involved cross-linking reaction. The formation of Fu/CS complex and cross-linking of CS with GP increased the acid resistance and reduced the swelling rate of CS ENF, while the covalent conjugation of CuS NPs provided CS ENF with durable Fenton-like catalytic activity. The CuS@ENF composite (ENFC) effectively adsorbed HO and near-infrared (NIR) light, enabling it to kill bacteria by photothermal and photocatalytic bactericidal effects.

Development of genipin-crosslinked and fucoidan-adsorbed nano-hydroxyapatite/hydroxypropyl chitosan composite scaffolds for bone tissue engineering.

Hydroxypropyl chitosan (HPCS) has recently attracted increasing attention in biomedical applications because it has enhanced water solubility, excellent biocompatibility, and better antioxidant and antibacterial activities compared with chitosan. However, HPCS doesn't meet the mechanical strength requirement in bone tissue engineering and is not suitable for cell adhesion and growth because of its hydrophilic nature and low crystallinity. In this study, nano-scaled hydroxyapatite (n-HA) and HPCS were synthesized, respectively, and then n-HA/HPCS nanocomposite scaffolds were developed by incorporating n-HA into HPCS matrix accompanied with crosslinking of HPCS by a naturally occurring compound, genipin (GP), which in turn greatly altered the hydrophilicity and mechanical properties.

Development of nanocomposite scaffolds based on biomineralization of N,O-carboxymethyl chitosan/fucoidan conjugates for bone tissue engineering.

Bone tissue engineering holds great promise and clinical efficacy for the regeneration of bone defects. In this study, an amphoteric N,O-carboxymethyl chitosan (NOCC) and fucoidan (FD) were covalently cross-linked via an amidation reaction to synthesize NOCC/FD composite hydrogels. The hydrogels were lyophilized and then three-dimensional scaffolds with interconnected macropores were obtained.

A Biodegradable Hemostatic Gelatin/Polycaprolactone Composite for Surgical Hemostasis.

Massive bleeding is the leading cause of battlefield-related deaths and the second leading cause of deaths in civilian trauma centers. One of the challenges of managing severe wounds is the need to promote hemostasis as quickly as possible, which can be achieved by using hemostatic dressings. In this study, we fabricated 2 kinds of gelatin/polycaprolactone composites with 2 ratios of gelatin/polycaprolactone, 1:1 and 2:1 (GP11 and GP21, respectively).