A multi-responsive and self-healing konjac glucomannan hydrogel crosslinked by dual dynamic bonds for smart banana preservation

A multifunctional crosslinker enables an intelligent, self-healing KGM hydrogel. • The hydrogel responds to pH, reactive oxygen species, and redox stimuli. • The smart coating extends banana shelf-life via synergistic barrier and antibacterial effects. In this study, a novel dual-terminal phenylboronic acid-functionalized quaternary ammonium crosslinker (DTDP-PBA) containing a disulfide linkage was synthesized to construct a konjac glucomannan (KGM)-based hydrogel. The hydrogel network formed through dynamic boronic ester crosslinking, offering rapid self-healing (within 5 min) and multi-stimuli responsiveness to pH, reactive oxygen species (ROS), and redox potential. As a banana preservation coating, the hydrogel exhibited low permeability to water vapor, CO 2 , and O 2 , good UV-shielding, and excellent biocompatibility, outperforming polyethylene film and pure KGM. Over 8 days of ambient storage, it reduced weight loss to 3.9%, kept decay rate below 13.9%, maintained firmness at 20.1 N, and delayed ethylene peak to day 7, thus retarding fruit softening and deterioration. This work provides a versatile dynamic covalent strategy for responsive polysaccharide materials and a high-performance smart coating for bananas and other perishable fruits. Download: Download high-res image (131KB) Download: Download full-size image