Novel ROS-scavenging hydrogel produced in situ crosslinking between cyclodextrin and cellulose for promoting diabetic wound healing

Diabetic wounds are usually difficult to heal due to the high content of blood sugar, excessive ROS, impaired immune response, and delayed angiogenesis. In this study, we developed the multiple bonds crosslinked hydrogel with the properties of drug release regulatory, antibacterial, angiogenic, and scavenging ROS for promote diabetic wound healing effectively. The hydrogel was fabricated by one-pot crosslinking of bamboo parenchymal cellulose and modified beta -cyclodextrin via multiple connections formed including hydrogen- and ester -bond. Results indicated that the composited hydrogel has a significantly large pore structure, which can absorb wound exudate effectively as dressing. Owing to the special network, the release of internal drugs from hydrogels was regulated by different response to the pH of physiological environment. Additionally, the cavity structure of cyclodextrin enables the drug to be released continuously for 96 h. According to the synergistic combination of the structures of pores and cavities, the composited hydrogel exhibited excellent capacities of drug loading and releasing. In vitro bacteriostasis experiments also affirmed that wound dressing (BPCAH-C) had a remarkable bacteriostasis effect against E. coli and S. aureus (bacteriostasis area up to 230 %). The prepared wound dressing can achieve a healing rate of 90 % within 14 days, meanwhile, the free radical clearance rate was reached 75 %. This kind of hydrogel dressing can accommodate and improve the change of microenvironment, has a broad application prospect in the clinical healing of diabetic wound.