Cefuroxime conjugated chitosan hydrogel for treatment of wound infections

Hydrogels are excellent drug delivery systems for the treatment of chronic wound infections. However, the problem of high burst release still remains a challenge that needs to be tackled. In terms of antibiotic release from the hydrogels, as the drug payload depletes it could act as a substrate for bacterial seeding which can create a life-threatening condition. Therefore, to provide the sustained effect of an antibiotic at the localized site via hydrogel matrix, we prepared a chitosan (CS) hydrogel system in which cefuroxime (CEF) is covalently conjugated with chitosan polymer via an ester linkage. To prepare the cefuroxime conjugated chitosan hydrogel, the formulations were optimized using different concentrations of cefuroxime, 0% (CS/CEF_0), 5% (CS/CEF_5), 10% (CS/CEF_10) and 20% (CS/CEF_20) w/w of chitosan. Fourier Transform Infra-red Spectroscopy (FTIR) confirmed the conjugation of cefuroxime and chitosan. The drug release studies showed that the release of cefuroxime was higher in the phosphate buffer (pH 7.4) with esterase enzyme and alkaline medium (pH 10) compared to phosphate buffer (pH 7.4) alone. Hemolysis assay was performed to demonstrate the hemocompatibility of the prepared hydrogel samples. The cell viability study using the L929 fibroblast and MG63 osteosarcoma cell lines revealed that synthesized hydrogel is biocompatible. Furthermore, a potent antibacterial activity for the extended time period proved the biological efficacy of a hydrolyzed cefuroxime. Thus, CS/CEF_5, CS/CEF_10, and CS/CEF_20 hydrogels have a promising future in the treatment of chronic wound infections.