Evaluation on preparation process of baicalin-Eudragit L100-55 enteric coated solid dispersion and its in vitro release / 中草药

ABSTRACT

Objective: To prepare the baicalin-Eudragit L100-55 (EL) enteric coated solid dispersion and to investigate the feasibility of this baicalin preparation. Methods: Baicalin-EL enteric coated solid dispersion was prepared by using solvent evaporation method. The microscopic structure and physicochemical properties of solid dispersion were analyzed using differential scanning calorimetry (DSC), scanning electron microscopy (SEM), X-ray powder diffraction (XRD), and infrared vibrational spectra (IR). And its in vitro release was also investigated. Results: DSC and XRD analyses suggested that baicalin may be present in enteric coated solid dispersion as amorphous substance. IR results indicated the presence of interactions between baicalin and EL. The in vitro release showed the accumulated dissolution rate of baicalin was less than 3% in artificial pH 1.2 dilute hydrochloric acid solution for 2 h, but an accumulated dissolution rate exceeding 90% in pH 6.8 phosphate buffer solution for 2 h when baicalin-EL ratio reached 16. Conclusion: Baicalin-EL enteric coated solid dispersion prepared could release drug rapidly and increase local drug concentration and then improve the oral absorption of baicalin.