Green Reduction of Graphene Oxide by Macromolecular CMCS to Prepare Self‐Healing Conductive Hydrogel Wound Dressing with Drug/Photothermal Antibacterial Activity

Abstract The healing of severe skin injury is a complicated process and the development of hydrogel dressing with antibacterial and stimuli responsive abilities is necessary. Recently, reduced graphene oxide (RGO) has been widely used in hydrogel dressings due to its good conductivity and photothermal effects. However, there still exist some problems in the fabrication of RGO‐modified hydrogels, especially in the green preparation and dispersion process of RGO. In this work, macromolecular carboxymethyl chitosan (CMCS) is chosen as the reducing agent for the green preparation of RGO. Hydrogels with antibacterial and stimulus‐responsive properties are constructed via Schiff base condensation between CMCS and oxidized pectin (OP). Over 95% cell viability is observed, which is critical for medical applications. RGO endows the hydrogels with relatively good conductivity, self‐healing properties, and mechanical strength. The diameters of bacteriostasis circle of the hydrogel for Escherichia coli and Staphylococcus aureus increase by 0.2 and 0.8 cm respectively after exposure to NIR for 5 min, resulting from the photothermal antibacterial properties of the hydrogel provided by RGO. This study provides guidance for the design and application of multifunctional wound dressing.