Enhanced wound healing activity of nano ZnO and nano Curcuma longa in third-degree burn

Abstract

Burns are caused by various external factors, such as radiation, chemicals, electricity, hot surfaces or liquids, which can seriously damage the integrity of the skin. Due to the lack of blood vessel formation, immunosuppression, and sensitivity to various infections, third-degree burns can damage the entire skin layer and delay the healing process. Therefore, this study was planned to evaluate the therapeutic effects of nano ZnO, nano CUR alone and in the composite form in third-degree burns. Topical 1% w/w skin ointments of nano ZnO, Curcuma longa (C. longa) nanoparticles (nano-CUR) and a composite of ZnO and C. longa nanoparticles (nano ZnO/CUR composite) were formulated for the treatment of burn wounds after characterization. A total of 25 rabbits from the animal house were grouped in 4 treatment (nano ZnO, nano CUR, nano ZnO/CUR and positive control) groups with 5 rabbits in each, while 5th group as a negative control group. These rabbits of four treatment groups were branded with the red-hot iron bar having a diameter of 10 mm for 15 seconds to create two burn wounds on each rabbit after induction of anesthesia. Healing time and wound contraction rate were conducted at 7th, 14th, 21st and 28th day after wound infliction while histopathological examination was conducted at 28th day after woud infliction. The statistical evaluation showed that nano ZnO/CUR composite group took less time to heal wound (avg, 24.25D ± 0.5) as compared to other groups of nano ZnO (26.25D ± 0.5), nano CUR (28D ± 0.82) and positive control (36.25D ± 0.5) with a similar pattern as observed for contraction rate of the wound. Histopathological analysis showed higher collagen deposition, vascularization, angiogenesis and fibrosis by nano ZnO/CUR composite treated group as compared to other groups. The study concluded that the application of nano ZnO/CUR composite ointment will heal third-degree burn wounds rapidly as compared to solus alone application.