Structure regulation of oxidized soybean cellulose nanocrystals/poly-acrylamide hydrogel and its application potential in wound dressing

The development of functional dressings based on natural polysaccharide-based hydrogels remains a great challenge, and the specific roles of gel composition and drug-controlled release mechanisms were unclear. In this study, oxidized soybean cellulose nanocrystals (CNCs)/poly-acrylamide (PAM) hydrogel was prepared. The proportion of CNCs, crosslinkers, and water in the system was regulated to fine-tune the rheological performances, texture properties, transparency, and micro-network structures of CNCs/PAM hydrogel, and further explored its application potential in the field of wound dressings. It was found that CNCs improved the rigidity and adhesion of hydrogels, crosslinkers improved the network density, and water promoted the softening and fluidity of hydrogels. The effective filling of CNCs in the composite hydrogel was verified by FTIR, XRD, and NMR. Furthermore, the pH responsiveness and drug-loading potential of the smart hydrogel were tested by swelling and drug-controlled release experiments, elucidating drug-release dynamic mechanisms during the wound healing process. The inhibition zones (>7 mm) of gram-positive/negative bacteria and cell viability (>100 %) assay showed satisfactory biocompatibility, as the hydrogel effectively accelerated wound healing in a wound model. These results elucidated the regulation mechanism of the structures of CNCs/PAM hydrogel and revealed the application potential of CNCs/PAM hydrogel in wound dressings.