Cellulose-Based pH-Responsive Janus Dressing with Unidirectional Moisture Drainage for Exudate Management and Diabetic Wounds Healing

Diabetic wounds with hyperglycemic tissue exudates and bacterial infections have become a great challenge that seriously delays the healing of diabetic wounds. Therefore, multifunctional  dressings for exudate management of diabetic wound are urgently needed. Herein, a smart dressing with rapid moisture-drained and non-adhesive, pH-responsive, and antibacterial capabilities is proposed for exudate management and wound monitoring. The Janus dressing is assembled with an antioxidant, pH-sensitive, and hydrophilic cellulose cover and an antibacterial hydrophobic polycaprolactone bottom layer that directly contacts with the wounds, which can unidirectionally and irreversibly drain the wound exudates and weaken the wet adhesion to the wound. In response to the humoral pH variations (5-9) during the healing process ofdiabetic wounds, the healing process can be in situ monitored according to the distinct pH-responsive colors of the Janus dressing at different healing stages. In vivo assays and histopathological studies suggest that the Janus dressing has a superior pro-healing rate, collagen deposition, and angiogenesis than commercial gauze. Notably, such a mulitfunctional dressing provides real-time wound monitoring simply through a smartphone integrated with Python-RGB programs, which can significantly alleviate the hyperglycemic exudate-flooded environment as an alternative strategy for diabetic wound treatment.