Synthesis of copolymer hydrogels based on maltodextrin and chitosan with antimicrobial properties for their potential...

This study reports the development of novel hydrogels based on two modified polysaccharides: maltodextrin (MD) and chitosan (CS), which were functionalized with glycidyl methacrylate (GMA) and maleic anhydride (MA), respectively. The poly(MD-co-CS) hydrogels, synthesized as potential vancomycin delivery systems, were optimized by varying the MD:CS weight ratio, crosslinker concentration, and reaction time. SEM images showed that the microstructure of poly(MD-co-CS) hydrogels was strongly influenced by the MD:CS ratio and NMBA crosslinker concentration. High MD content leads to dense, low-porosity structures, while high CS content results in irregular, less organized morphologies. Optimal pore formation was achieved with a 1:1 MD:CS ratio and low NMBA concentrations (2.5-5 %). As consequence, these hydrogels demonstrated high-water absorption capacity, with swelling ratios reaching up to 600 %. Drug release studies revealed that the hydrogel synthesized with 2.5 % of NMBA released 66 % of the drug, while the 5 % NMBA hydrogel released only 27 %. The antimicrobial activity, assessed via the disk diffusion method, showed effective inhibition against both Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), with a notably larger inhibition zone observed for E. coli (31 ± 1 mm), confirming the antibacterial efficacy of the vancomycin-loaded hydrogels. In vitro biocompatibility tests using human fibroblast 1132SK cells demonstrated 100 % of viability after 24 h of exposure to the poly(MD-co-CS) hydrogel containing 2.5 % NMBA. These findings suggest that the developed hydrogels are promising candidates for application as wound dressings.