An Alternative Lidocaine Hydrochloride Liposomal Gel Formulation: Preparation, Percutaneous Permeation, and Release Kinetics

Abstract

Liposomal hydrogel formulations of lidocaine hydrochloride (LDH), suitable for topical application, were prepared, and drug percutaneous permeation and release properties were evaluated in vitro. Liposomes composed of lechitin and cholesterol, with LDH entrapped in the inner water compartment, were prepared by the reverse-phase evaporation technique. An optimal hydrogel formulation with carbopol as base included permeation enhancers polyethylene glycol (PEG-400), Azone, poloxamer, and propylene glycol, and this was screened in vitro. Percutaneous permeation kinetic models of LDH in three formulations, liposome solution, conventional gel, and liposomal gel, were studied. Results showed that the mean diameter of LDH liposomes was 88.31 ± 6.82 nm and entrapment efficiency was 66.21 ± 4.8%. The percutaneous permeation rate of LDH across skin from gel increased after LDH was entrapped in the water compartment of liposome compared with conventional gel, and the permeation kinetics of LDH across skin was not linear, but followed the Higuchi function.