Determination of Cholic Acid and Taurohyodeoxycholic Acid in Compound Pancreatin Tablets by HPLC

A method was established for the determination of cholic acid and taurohyodeoxycholic acid in compound pancreatin tablets by HPLC. The samples (0.3 g and 0.5 g) were respectively taken out of 10 ground compound pancreatin tablets, dissolved with methanol, and extracted ultrasonically for 30 min. The extracts were made their volume up to 50, 25 mL with methanol respectively. The obtained solution was separated on SunShell HFC₁₈-30 column for cholic acid, and Diamonsil C₁₈ column for taurohyodeoxycholic acid. A mixture of acetonitrile and 0.1% (φ) phosphoric acid solution at a volume ratio of 35∶65 was used as the mobile phase, and the detection wavelength was 192 nm. Under the optimized test conditions, linear relationships between values of peak area and mass concentration of cholic acid and taurohyodeoxycholic acid were found in definite ranges, with detection limits (3S/N) of 11.0 mg·L^-1 and 5.61 mg·L^-1, respectively. Test for recovery was made by standard addition method, giving results of 91.9% and 102%, and RSDs (n=6) of the determined values less than 5.0%.