Topical delivery of mupirocin calcium nanostructured lipid carriers using a full-thickness excision wound healing model

Objective: Treatment of contaminated wounds represents a significant challenge in healthcare and there is a need to develop approaches maximising skin retention to maintain therapeutic concentrations of anti-infectives at the wound site. The objective of the present study was to develop and evaluate mupirocin calcium nanolipid emulgels to enhance wound healing performance and patient acceptability. Methods: Nanostructured lipid carriers (NLCs) of mupirocin calcium were prepared by the phase inversion temperature method using Precirol ATO 5 (Gattefosse, India) and oleic acid as lipids and Kolliphor RH 40 (BASF, India) as surfactant and further incorporated into a gel base for topical delivery. Results: The particle size, polydispersity index and zeta potential of mupirocin NLCs were found to be 128.8 +/- 1.25nm, 0.283 +/- 0.003 and -24.2 +/- 0.56mV, respectively. In vitro release studies from developed emulgel showed sustained drug release over 24 hours. Ex vivo drug permeation studies through excised rat abdominal skin showed better skin permeation (1712.38 +/- 15. 57 mu g/cm(2)) from developed emulgel compared to marketed ointment (827.92 +/- 21.42 mu g/cm(2)) after 8 hours, which was in agreement with in vitro antibacterial activity. Studies on Wistar rats indicated the nonirritant potential of developed emulgels. Further, mupirocin emulgels showed improved efficacy in percent wound contraction of acute contaminated open wounds in Wistar rats using a full-thickness excision wound healing model. Conclusion: The emulgels of mupirocin calcium NLCs appear to be effective in the treatment of contaminated wounds due to increased skin deposition and sustained release, thereby enhancing the wound healing potential of existing molecules.