Novel Double Cross-Linked Acrylic Acid/Bagasse Cellulose Porous Hydrogel for Controlled Release of Citral and Bacteriostatic Effects

In this study, double cross-linked acrylic acid/bagasse cellulose (AA/BC) porous hydrogels were first prepared using cold plasma (CP) technology instead of chemical initiators. The structure and properties of porous hydrogels, as well as the controlled release and bacteriostatic application as functional carriers, were investigated. Results showed that a novel double cross-linked hydrogel had been successfully synthesized by utilizing ^•OH and H⁺ produced during plasma discharge. The acrylic acid (AA) monomers were successfully grafted onto the main chains of bagasse cellulose (BC), forming a porous three-dimensional network structure. The AA/BC porous hydrogels showed excellent swelling levels and intelligent responses. The release of citral in hydrogel inclusion compounds embedded with citral was controlled by adjusting the pH, and the slow release period was about 2 days. The inclusion compounds presented strong bacteriostatic effects against Escherichia coli and Staphylococcus aureus, extending the shelf life of fruits for about 4 days. Therefore, it can be concluded that CP technology is considered to be an efficient and environmental-friendly initiation technology for preparing hydrogels. The potential application of hydrogel inclusion compounds in the food field is expanded.