A Mg ²⁺/polydopamine composite hydrogel for the acceleration of infected wound healing

Abstract

Bacterial infection is a vital factor to delay the wound healing process. The antibiotics abuse leads to drug resistance of some pathogenic bacteria. Non-antibiotic-dependent multifunctional biomaterials with accelerated wound healing performance are urgently desired. Herein, we reported a composite antibacterial hydrogel PDA-PAM/Mg ²⁺ that shows excellent self-healing and tissue adhesive property, and photothermal antibacterial functions for accelerating wound healing. The gel was composed of polyacrylamide (PAM), polydopamine (PDA), and magnesium (Mg ²⁺) and prepared via a two-step procedure: an alkali-induced dopamine pre-polymerization and followed radical polymerization process. The composite gel shows excellent tissue adhesiveness and Mg ²⁺-synergized photothermal antibacterial activity, inducing a survival rate of 5.29% for S. aureus and 7.06% for E. coli after near infrared light irradiation. The composite hydrogel further demonstrated efficient bacteria inhibition, enhanced wound healing and collagen deposition in a full-thickness skin defect rat model. Together, the PDA-PAM/Mg ²⁺ hydrogel presents an excellent wound dressing with excellent tissue adhesion, wound healing, and antibacterial functions.

Graphical abstract

Highlights

• •

  A self-healing multifunctional hydrogel with photothermal antibacterial properties was developed and applied in wound healing.

• •

  The hydrogel exhibited enhanced self-healing and adhesion properties.

• •

  The hydrogel exhibited excellent photothermal effect and photothermal stability and repeatability.

• •

  The hydrogel could accelerate wound healing by promoting cell proliferation and collagen deposition.