Anthocyanidin-Loaded Superabsorbent Self-Pumping Dressings for Macrophage Immunomodulation and Diabetic Wound Healing

Management of diabetic chronic wound exudate is a serious challenge in healthcare worldwide since it is related to the speed of diabetic wound healing. However, current foam dressings not only absorb fluid to generate swelling and compress the wound to hinder wound healing but also are very thick and less comfortable to use. Herein, a superabsorbent self-pumping ultrathin dressing is reported to accelerate diabetic wound healing by achieving superior exudate absorption and management in an ultrathin state. The self-pumping dressing is composed of a drainage layer loaded with anthocyanidin and a thermoplastic polyurethane absorbent layer embedded with superabsorbent particles. The dressing realizes the self-pumping process of unidirectional exudate draining to the absorption layer through the drainage layer without significant dressing swelling to compress the diabetic wound. The dressing is experimentally proven to unidirectionally drain excessive exudate with inflammatory factors and modulate the conversion of macrophages from M1 to M2 in diabetic wounds, thereby promoting the healing of diabetic skin ulcers faster than commercial foam dressings. Therefore, the dressing provides a new idea and novel method for accelerating diabetic skin ulcer healing.