LAUSR

Abstract The treatment of acne warrants development of formulation aiming to enhance topical delivery with minimum systemic absorption. The aim of present study was to develop, optimize and characterize clindamycin phosphate-loaded nanostructured lipid carriers (CP-NLC) gel for enhanced topical delivery. CP-NLC was prepared using melt emulsification comibined with sonication technique using oleic acid (liquid lipid), precirol ATO5 (solid lipid), and tween 80 (surfactant). The optimized formulation attained using Box-Behnken statistical design exhibited particle size of 136 ± 0.11 nm, narrow PDI (0.256 ± 0.10), and high entrapment efficiency and high drug loading. TEM and SEM studies confirmed the spherical nature of the particles. Further, CP-NLC was loaded into Carbopol®940 gel and 1% concentration was evaluated for in vitro studies. The drug release from CP-NLC gel was 1.5-fold greater than from marketed formulation Clindac A®. The cumulative drug permeated through the skin was also found to be higher for CP-NLC gel (1.6-fold) than Clindac A® gel. The skin retention study, tape stripping technique and confocal laser scanning microscopy demonstrated enhanced skin retention and depth of permeation for CP-NLC gel. Therefore, formulating NLC for topical delivery of CP will render many benefits over marketed formulation thus proving as a promising carrier in the treatment of acne.