Enhanced topical delivery of dutasteride using PLGA nanoparticles

Androgenic alopecia (AGA) is the most studied scalp disease, due to its diffusion among men an women; its cause is the conversion of testosterone to Dihydrotestosterone by the enzyme 5α-reductase type II, that is located in the hair follicle’s oil glands. The objective of this study was to investigate methods of topical application of Dutasteride, both type I and II 5α-reductase inhibitor, using PLGA particles as a delivery system, in order to avoid the side effects that an oral application could cause. The skin is an efficient barrier and limits the skin permeation of exogenous substances, drugs included. Because of this property, it is difficult to deliver therapeutic agents through the skin and various chemicals has been studied as possible penetration enhancers or adsorption promoters. Hair follicle drug delivery is an important pathway for dermal penetration, and could be a promising way to deliver drugs using nanoparticles. Over the last two decades PLGA has generated great interest as a carrier for bioactive materials due to its excellent biocompatibility and biodegradability. Due to its lipophilic nature, dutasteride is well suited to PLGA encapsulation process. Dutasteride-loaded PLGA (50:50)nanoparticles have been prepared using the nanoprecipitation method. It was anticipated that these particles allow dutasteride deposition in the pilosebaceous unit. The size and morphology of the particles have been evaluated using scanning electron microscopy and dynamic light scattering. The dutasteride-loading efficiency had been determined using an analysis. Finally, a mixture of dutasteride-loaded PLGA nanoparticles and fitch-loaded PLGA nanoparticles have been used in order to study the efficacy and the depth of penetration in vitro, using a Franz diffusion cell and a confocal microscope.