Impacting different structures of injectable pluronic-conjugated alginate (chitosan) hydrogels on their physicochemical characteristics and morphological fibroblast behavior

Chitosan and alginate have inherent properties that have a tremendous impact on the design of in situ thermal sensitive hydrogels due to their ability to fill complex three-dimensional damaged tissue gaps, which can be applied in the tissue regeneration or drug delivery systems. In this study, pluronic F127-conjugated alginate (Alg-F127) and pluronic F127-conjugated chitosan (CS-F127) copolymers were investigated for their physicochemical characteristics and morphological fibroblast behavior. The structures of the amphiphilic copolymers were characterized by 1H-NMR. The aqueous copolymer solution could reversibly change its state from sol to gel via hydrophobic interactions at body temperature (35°–37 °C). At the same concentration of two grafted copolymers, the alginate-based hydrogel performed higher resistance to degrade in both PBS buffer and DMEM. Regarding their specific charge, CS-F127 showed higher protein absorption as compared to the Alg-F127 copolymer. The typical characteristic could induce the different morphological cell behaviors on the hydrogel platforms. Interestingly, as an inherent characteristic of fibroblasts, the cells were elongated and migrated directionally on the Alg-F127 scaffold, though both had excellent cytocompatibility. The improved understanding of the influence of polysaccharide structure on cell behavior has a significant impact on the design of biomedical devices and specific tissue regeneration.