Design, optimization and in-vivo characterization of mupirocin loaded nanostructured lipid carrier based gel for effective treatment of impetigo

Mupirocin is a broad-spectrum antibiotic effective in treatment of skin infection (Impetigo), but the poor bioavailability limits its use as a conventional dosage form such as tablets, ointment and cream. The present investigation was aimed to design, optimize and evaluate Mupirocin (MC) loaded nanostructured lipid carriers (NLCs) based gel for topical application. Excipients identified were screened for apposite material required for the formulation of NLCs using process variables as the determining factors. The preparation of nanostructured lipid carriers (NLCs) was optimized using 3(2) factorial design with two independent variables (solid: liquid lipid ratio and surfactant (%)) and two responses (particle size (nm), entrapment efficiency (%)) using hot high pressure homogenization method. The formulation was further characterized for zeta potential (mV), polydispersity index and morphology. The optimized NLC dispersion of Mupirocin (MC) was lyophilized and loaded in 0.75% w/v Carbopol 980 gel and was evaluated for pH, viscosity and drug content. Mupirocin (MC) loaded NLC based gel were characterized for ex-vivo drug permeation and compared with marketed (cream) preparation. Further, drug deposition, skin irritation and stability study was carried out as per ICH guidelines. The optimized formulation (F5) containing Glyceryl behenate: Oleic acid (70:30), and Poloxamer 188 (0.5%) demonstrated smaller particle size (150.02 +/- 1.52 nm) with higher drug entrapment efficiency (88.02 +/- 1.21%). Mupirocin (MC) loaded NLC based gel demonstrated sustained drug profile with significant increase (P < 0.05) in drug deposition in skin (about 26%) with non-irritant properties to the skin. Stability study showed no significant changes of the parameters during and after the study. In conclusion, developed Mupirocin (MC) loaded NLC based gel could serve as a novel approach in treatment of impetigo by deliver the drug topically with sustained effect and improved patient compliance.