Facile and Low-Cost Electrochemical Synthesis of Zinc Alginate Hydrogel Films for Biomedical Applications

Abstract

Electrochemical synthesis and characterization of Zn-alginate hydrogel films and their antioxidant and antimicrobial activity are evaluated. Swelling properties, zinc concentration and spectroscopic and morphological features were characterized and related to their antimicrobial and antioxidant activity. These results indicate a dependence of swelling on the degree of cross-linking, which, in turn, can be adjusted by manipulating the synthesis time, initial alginate concentration and/or zinc leaching. Hydrogel films with zinc showed remarkable antibacterial properties, especially against gram-positive bacteria. The absence of Zn resulted in less inhibition of gram-positive strains, although it had a positive effect on the inhibition of gram-negative strains, which was attributed to the degradation of alginate chains, affecting cell metabolism. Nitrogen-doped samples synthesized in rivanol-containing solution exhibited globular morphology and higher antioxidant activity. The electrochemical synthesis enables the facile preparation of highly active alginate hydrogels for biomedical applications.