Stimuli-responsive drug delivery, antioxidant and photothermal antibacterial hydrogel wound dressing for MRSA-infected pressure ulcer repair

Abstract

Chronic wounds are a big challenge in the healthcare area and their high happening frequency leads to heavy burdens on the economy. A pressure ulcer is one of the most happened chronic wounds and brings a lot of pain to patients. To date, efficient treatment for pressure ulcers is still lacking and the main challenges of pressure ulcer control are avoiding infection, diminishing inflammation, and promoting repair.In this study, we developed a smart wound dressing based on 3-aminophenylboronic acid (HA-PBA) and dopamine (DA) modified hyaluronic acid (HA-DA) via the dynamic phenylboronic acid ester bonds. By loading with quercetin via chemical bonds, the drug can be released on demand when stimulated with pH changes and H 2 O 2 , due to the phenylboronic acid ester bonds' sensitivity to these factors. Besides the flexibility, injectability, and self-healing properties, this smart dressing also showed excellent antibacterial properties against MRSA and E. coli, because of the photothermal behavior of this hydrogel endowed by polydopamine (PDA). Due to the synergistic effects of phenylboronic acid ester bonds and quercetin, this hydrogel showed acute and long-term anti-oxidant properties. In vitro study indicates this wound dressing has good blood and cell compatibility. When treating the pressure ulcer model mouse with this wound dressing, it showed great control of infection, as well as promotion of granulation tissue generation, re-epithelialization, and angiogenesis, indicating that this smart hydrogel is a promising wound dressing for pressure ulcer wounds.