Preparation and evaluation of chitosan-coated PLGA nanoparticles for improved skin permeation of testosterone

Abstract

The aim of this study is to investigate testosterone-loaded PLGA nanoparticles with chitosan coating (CS-TS-PLGA NPs) for improved skin permeation. CS-TS-PLGA NPs were prepared by using spontaneous emulsification solvent diffusion (SESD) method with PLGA, poloxamer 188 and chitosan. The physicochemical properties of CS-TS-PLGA NPs were characterized in terms of particle size, polydispersity index, zeta potential, entrapment efficiency and loading capacity. The entrapment of testosterone in CS-TS-PLGA NPs was confirmed by differential scanning calorimetry and powder X-ray diffractometry. In vitro skin permeation of testosterone was evaluated using Franz diffusion cell and skin permeation parameters were compared between CS-TS-PLGA NPs and TS-PLGA NPs without chitosan coating. The optimized compositions of CS-TS-PLGA NPs was determined as 2:1:0.1:1 (w/w ratio, PLGA:poloxamer 188:chitosan:testosterone). CS-TS-PLGA NPs showed mean diameter of 223.9 nm with narrow particle size distribution. The entrapment efficiency and loading capacity of CS-TS-PLGA NPs were 35.30% and 7.44%, respectively. The stability of CS-TS-PLGA NPs was maintained for 3 months without significant changes in particle size, polydispersity index and zeta potential. CS-TS-PLGA NPs showed sustained release compared with TS solution and TS-PLGA NPs. The TS release half-life of CS-TS-PLGA NPs remarkably increased up to 4 times (from 30 min to 120min) than in TS solution via sustained TS release. The skin permeation parameters of CS-TS-PLGA NPs were 3.69 times higher than that of TS solution and TS-PLGA NPs. In conclusion, the optimized CS-TS-PLGA NPs could be promising nanocarriers for effective delivery of TS via skin