Preparation and characterization of dextran-modified ZnO and Cu-doped ZnO nanohybrid material for enhanced antimicrobial delivery and activity

Zinc oxide (ZnO) nanoparticles are widely used in various applications, particularly in antimicrobial products. Efforts to enhance their performance and efficacy, including copper (Cu) doping and incorporating natural polymers. In this study, dextran-modified ZnO and Cu-doped ZnO nanohybrids were synthesized and characterized using exodextran isolated from Leuconostoc mesenteroides TISTR 473. Characterization results showed that dextran binds to the surface of ZnO particles through CO⋯Zn and C-OH⋯O interactions, particularly at oxygen vacancy sites. The incorporation of dextran improved the antibacterial efficacy of ZnO and Cu-doped ZnO nanoparticles against bacteria related to fruit and vegetable spoilage, including gram-positive Bacillus altitudinis and gram-negative Achromobacter mucicolens. These findings highlight the potential of dextran-modified ZnO nanomaterials in enhancing antimicrobial activity and biocompatibility for biomedical applications, as well as their use in food packaging to extend shelf life.