Enhancing the oral bioavailability of baicalein via Solutol ® HS15 and Poloxamer 188 mixed micelles system

Abstract

Objectives: To increase the solubility of baicalein (BAI) by preparing BAI-micelles (BAI-M) with Solutol HS15 (HS15) and Poloxamer 188 (F68), thereby improving its oral bioavailability. Methods: Baicalein micelles were prepared with HS15 and F68 by thin-film dispersion method and optimized by central composite design (CCD) approach. Physicochemical, in vitro release, Caco-2 cell transport and pharmacokinetic studies of BAI-M were performed. Key findings: The optimal formulation showed spherical shape by characterization of the transmission electron microscope with average small size (23.14 ± 1.46 nm) and high entrapment efficiency (92.78±0.98%) and drug loading (6.45±1.54%). The in vitro release study of BAI-M showed a significantly sustained release pattern compared with free BAI. Caco-2 cell transport study demonstrated that high permeability of BAI was achieved after loading it into micelles. Meanwhile, pharmacokinetics study of BAI-M showed a 3.02-fold increase in relative oral bioavailability compared with free BAI. Conclusions: Based on our findings, we concluded that HS15 can be used as a carrier in this drug delivery system that includes F68, and BAI-M has great potential in improving solubility and oral bioavailability.