Microencapsulation of Poorly Water-soluble Finasteride in Polyvinyl Alcohol/chitosan Microspheres as a Long-term Sustained Release System for Potential Embolization Applications
Abstract
Prostatic artery embolization (PAE) has been widely applied as an alternative option to treat symptomatic benign prostatic hyperplasia (BPH). However, hitherto, very few drug-loaded embolic materials have been developed to improve the therapeutic efficacy of PAE. In this study, the poorly water-soluble finasteride (FNS) was micronized via a homogenization technique in the presence of a hydrophilic surfactant, followed by encapsulating the crystalline FNS dispersion in polyvinyl alcohol/chitosan (PVA/CS) matrix via emulsification crosslinking method. The prepared FNS-loaded PVA/CS microspheres (FNS@PVA/CS MS) were characterized for their physicochemical properties. Results showed that the MS were well-dispersed and spherical, with an average particle size of 191.5 μm. The FNS was presented in crystalline form inside the MS, which exhibited controlled and sustained release of FNS up to 45 days. In vitro biocompatibility evaluations indicated that the MS were non-cytotoxic and hemocompatible. Moreover, in vivo transauricular embolization studies in rabbits revealed the effective occlusion of the MS in the auricular central arteries, and exhibited superior embolization effects. Furthermore, the persistent embolization resulted in prominent ultrastructural alternations of endothelial cells in ischemic necrosis region. These results suggest that the drug-delivering MS could be a promising embolic agent for BPH therapy.