Enzyme-Activated Multifunctional Hydrogel for Real-Time Monitoring and Photothermal Therapy of Infected Wounds.

Bacterial infected wounds pose a serious threat to human health. Developing a novel strategy that integrates real-time infection monitoring with exceptional antibacterial performance is urgent for advancing wound management. Herein, a multifunctional hydrogel (CMCS-PA@Fe/MUG hydrogels) integrating real-time infection diagnosis and therapeutic intervention capabilities has been successfully developed through the formation of Schiff bases between CMCS and PA@Fe solutions with the addition of 4-methylumbelliferyl β-d-glucuronide (MUG). The detection of the bacterial presence is achieved by visually monitoring the blue fluorescence emitted from 4-methylumbelliferyl (4-MU), which is produced through the enzymatic hydrolysis of MUG by pathogen-specific enzymes. In addition, the tissue adhesion and self-healing properties of CMCS-PA@Fe/MUG hydrogels enable them to seamlessly adapt to the mechanical demands of skin movement and stretching. Moreover, the combined photothermal activity of PA@Fe and the intrinsic antibacterial capability of chitosan endow the hydrogel with a superior antibacterial performance. The in vivo experimental results demonstrate that the hydrogel could effectively diagnose the infection status of a wound in real time and promote wound healing. Therefore, this advanced hydrogel sensor provides an innovative solution for infected wound management through real-time infection monitoring and efficient antibacterial strategies.