Development and Characterization of Topical Microemulsion of Levofloxacin

In the present work, levofloxacin based microemulsion was developed and its usefulness as topical drug carrier system for anti bacterial activity was investigated. Microemulsion was prepared by phase titration method using oleic acid as oil phase, tween-60 as surfactant and isopropyl alcohol as co-surfactant. Five different formulations were formulated with various amount of the oil, water and the mixture of surfactant and co-surfactant. Different formulations were prepared to evaluate the effect of oil content, surfactant/ cosurfactant concentration on in-vitro permeation rates. Microemulsions were characterized for pseudo-ternary phase diagrams, pH, viscosity, droplet size, in-vitro release profile and stability evaluation. In-vitro skin permeability of levofloxacin from the microemulsion was evaluated using franz diffusion cell method. The optimized microemulsion formulation was found to be o/w type emulsion by pseudo-ternary phase diagram. These results indicate that the microemulsion system studied is a promising tool for the topical delivery of levofloxacin.