Chenodeoxycholic acid correlation determination method is similar to UDCA, there is no good versatility, specificity of the determination method, in a variety of cholic acid drugs, there are bezoar, pig and other drugs, UDCA and chenodeoxycholic acid determination of the method still has practical significance; HPLC / MS method and Evaporative Scattering Detector (EDSL) will become the main instrument and means of UDCA and chenodeoxycholic acid measurement.
Ursodeoxycholic acid in bear bile powder, UDCA mainly exists in the form of taurine binding, that is, taurine ursodeoxycholic acid, the combination of TUDCA content, the general use of high performance liquid chromatography. At present, the content of bound TUDCA is determined by high performance liquid chromatography (HPLC), which is used as the quantitative standard of the quality of bear bile powder. HPLC method for the determination of UDCA, the use of ion suppression in the pH 2 ~ 3 under strong acidic conditions, 200nm near the test can be detected; because the maximum response wavelength of cholic acid in the 200nm low wavelength region, the instrument noise level is high, the sensitivity is low. Select the appropriate derivatization reagents such as aniline, phenylhydrazine and so on, pre-column derivatization reaction, connected to the UV absorption group, measured wavelength above 230nm, thus avoiding the noise interference.
The determination of UDCA content, Pharmacopoeia 2000 edition to acid-base titration method for the quantitative method, the method for low concentrations can not be determined for multi-component acidic bile acid can not be quantified. Pharmacopoeia 2005 edition of the thin layer method as a quantitative method, TLC and HPTLC analysis of bile acids widely used. Cholesterol GC analysis, the main method is to first hydrolyze the sample, and then derivatization, complex and time-consuming; but Keller and others using GC-MS-SIM cholesterol and cholic acid were non-derivative analysis, the determination of seven kinds of feces cholic acid. HPLC / MS mass spectrometry also obtained a good separation effect.