title: Preparation, characterization and in vivo assessment of the bioavailability of glycyrrhizic acid microparticles by supercritical anti-solvent process.
abstract: In this study, glycyrrhizic acid (GA) microparticles were successfully prepared using a supercritical anti-solvent (SAS) process. Carbon dioxide and ethanol were used as the anti-solvent and solvent, respectively. The influences of several process parameters on the mean particle size (MPS), particle size distribution (PSD) and total yield were investigated. Processed particle sizes gradually decreased as temperature and solution flow rate increased. In addition, processed particle sizes increased from 119 to 205 nm as GA concentration increased. However, CO(2) flow rate did not significantly affect particle size. The optimized process conditions were applied, those included temperature (65 °C), pressure (250 bar), CO(2) and drug solution flow rate (15 and 8 mL min(-1)), drug concentration in ethanol (20 mg mL(-1)). Microparticles with a span of PSD ranging from 95 and 174 nm, MPS of 128 nm were obtained, and total yield was 63.5%. The X-ray diffraction patterns of glycyrrhizic acid microparticles show apparent amorphous nature. Fourier transform infrared (FT-IR) spectroscopy results show that no chemical structural changes occurred. The in vitro dissolution tests showed that the GA microparticles exhibited great enhancement of dissolution performance when compared to GA original drug. Furthermore, the in vivo studies revealed that the microparticles provided improved pharmacokinetic parameter after oral administration to rats as compared with original drug.
authors.affiliation: Key Laboratory of Forest Plant Ecology, Ministry of Education, Northeast Forestry University, Harbin 150040, China.
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Sui
authors.forename: Wei
authors.initials: W
authors.lastname: Wei
authors.forename: Lei
authors.initials: L
authors.lastname: Yang
authors.forename: Yuangang
authors.initials: Y
authors.lastname: Zu
authors.forename: Chunjian
authors.initials: C
authors.lastname: Zhao
authors.forename: Lin
authors.initials: L
authors.lastname: Zhang
authors.forename: Fengjian
authors.initials: F
authors.lastname: Yang
authors.forename: Zhonghua
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001682:Biological Availability; D002152:Calorimetry, Differential Scanning; D002245:Carbon Dioxide / Q000737:chemistry; D002626:Chemistry, Pharmaceutical; D025924:Chromatography, Supercritical Fluid; D018360:Crystallography, X-Ray; D004339:Drug Compounding; D000431:Ethanol / Q000737:chemistry; D019695:Glycyrrhizic Acid / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics*; D008297:Male; D053758:Nanoparticles; D036103:Nanotechnology; D010316:Particle Size; D011312:Pressure; D051381:Rats; D017208:Rats, Wistar; D012995:Solubility; D012997:Solvents / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013678:Technology, Pharmaceutical / Q000379:methods; D013696:Temperature; D013818:Thermogravimetry
chemical_list: D012997:Solvents; D002245:Carbon Dioxide; D000431:Ethanol; D019695:Glycyrrhizic Acid