Development of a Novel Bilosomal System for Improved Oral Bioavailability of Sertraline Hydrochloride: Formulation Design, In Vitro Characterization, and Ex Vivo and In Vivo Studies

This study was proposed to develop an optimized sertraline hydrochloride (SER)-loaded bilosomal system and evaluate its potential for enhancement of drug oral bioavailability. A full 2(3) factorial design was used to prepare SER-loaded bilosomal dispersions by thin film hydration using span 60, cholesterol (CHL), and sodium deoxycholate (SDC). The investigated factors included the total concentration of span 60 and CHL (X-1), span 60:CHL molar ratio (X-2), and SER:SDC molar ratio (X-3). The studied responses were entrapment efficiency (EE%) (Y-1), zeta potential (Y-2), particle size (Y-3), and in vitro % drug released at 2 (Y-4), 8 (Y-5), and 24 h (Y-6). The selected optimal bilosomal dispersion (N1) composition was 0.5% w/v (X-1), 1:1 (X-2), and 1:2 (X-3). Then, N1 was freeze dried into FDN1 that compared with pure SER for in vitro drug release, ex vivo permeation through rabbit intestine, and in vivo absorption in rats. Moreover, storage effect on FDN1 over 3 months was assessed. The optimal dispersion (N1) showed 68 +/- 0.7% entrapment efficiency, - 41 +/- 0.78 mV zeta potential, and 377 +/- 19 nm particle size. The freeze-dried form (FDN1) showed less % drug released in simulated gastric fluids with remarkable sustained SER release up to 24 h compared to pure SER. Moreover, FDN1 showed good stability, fivefold enhancement in SER permeation through rabbit intestine, and 222% bioavailability enhancement in rats' in vivo absorption study compared to pure SER. The SER-loaded bilosomal system (FDN1) could improve SER oral bioavailability with minimization of gastrointestinal side effects.