Preparation and characterization of baicalein powder micronized by the SEDS process

Baicalein, a bioactive flavonoid, exhibits various pharmacological activities and other beneficial effects, but its poor solubility and dissolution rate restrict its oral intestinal absorption rate and bioavailability. In this study, micronized baicalein was prepared by utilizing the technique of solution-enhanced dispersion by supercritical fluids (SEDS). Preparation, characterization, and the potential use of microparticles to improve the in vitro release of baicalein were studied. In vitro characterization data were obtained through Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), X-ray powder diffractometry (XRD), and scanning electron microscopy (SEM). The in vitro dissolution of the prepared microparticles was investigated and compared with raw powder. The results demonstrated that the prepared baicalein microparticles appeared as small flake shapes with a mean particle size (PS) of 0.614   μm under the appropriate conditions (solvent mixture of DCM and DMSO (5/1, v/v), drug concentration   =   7   mg/mL, pressure   =   16   MPa, and temperature   =   308   K) without an observed change in the crystal form. Additionally, the reduced PS of baicalein microparticles contributed to the enhanced dissolution rate.