The
on-demand replacement of multifunctional hydrogel
wound dressings
helps to avoid bacterial colonization, and the on-demand painless
peeling of tissue adhesive hydrogels on the wound site remains a major
challenge to be solved. In this work, we design and develop a series
of multifunctional dynamic Schiff base network hydrogels composed
of cystamine-modified hyaluronic acid, benzaldehyde-functionalized
poly(ethylene glycol)-co-poly(glycerol sebacate), and polydopamine@polypyrrole
nanocomposite (PDA@PPy) with mild on-demand removability to enhance
drug-resistant bacteria-infected wound healing. These hydrogels exhibited
ideal injectable and self-healing properties, excellent tissue adhesion,
in vivo hemostasis, good antioxidation, and conductivity. PDA@PPy
inspired by melanin endows hydrogels with excellent antioxidant capacity,
UV-blocking ability, and photothermal anti-infection ability. Based
on the dynamic oxidation–reduction response of disulfide bonds
inspired by the dissociation of the tertiary spatial structure transformation
of poly-polypeptide chains, these hydrogels can achieve rapid painless
on-demand removal under mild conditions by adding dithiothreitol.
These multifunctional hydrogels significantly promoted collagen deposition
and angiogenesis in the MRSA-infected full-thickness skin repair experiment.
All the results showed that these multifunctional hydrogels with painless
on-demand removal property showed great potential in clinical treatment
of infected wounds.