Abstract

A biodegradable in situ gel-forming controlled drug delivery system composed of curcumin loaded micelles and thermosensitive hydrogel was prepared and applied for cutaneous wound repair. Curcumin is believed to be a potent antioxidant and anti-inflammatory agent. Due to its high hydrophobicity, curcumin was encapsulated in polymeric micelles (Cur–M) with high drug loading and encapsulation efficiency. Cur–M loaded thermosensitive hydrogel (Cur–M–H) was prepared and applied as wound dressing to enhance the cutaneous wound healing. Cur–M–H was a free-flowing sol at ambient temperature and instantly converted into a non-flowing gel at body temperature. In vitro studies suggested that Cur–M–H exhibited well tissue adhesiveness and could release curcumin in an extended period. Furthermore, linear incision and full-thickness excision wound models were employed to evaluate the in vivo wound healing activity of Cur–M–H. In incision model, Cur–M–H-treated group showed higher tensile strength and thicker epidermis. In excision model, Cur–M–H group exhibited enhancement of wound closure. Besides, in both models, Cur–M–H-treated groups showed higher collagen content, better granulation, higher wound maturity, dramatic decrease in superoxide dismutase, and slight increase in catalase. Histopathologic examination also implied that Cur–M–H could enhance cutaneous wound repair. In conclusion, biodegradable Cur–M–H composite might have great application for wound healing.