The quality assessment of compound liquorice tablets by capillary electrophoresis fingerprints

Capillary electrophoresis (CE) is a powerful separation technique that is peculiarly able to determine the fingerprints of traditional Chinese medicine. The Capillary Electrophoresis Fingerprints (CEFP) of compound liquorice tablets (CLTs) was established to evaluate the quality of CLTs. The background electrolyte was a 50 mM sodium borate solution. The detection wavelength was 228 nm and a 14 kV voltage was applied. Hydrochlorothiazide served as an internal standard and temperature was 24-25 degrees C. The CLTs were extracted by a 50 mM borate solution containing 10% (v/v) methanol. The results showed that CE was a powerful tool for detecting of the fingerprints of traditional Chinese medicine and their constituents. The quality assessments were performed to compare the correlation coefficients (R) and cos theta (C) between each batch vector of CLTs and the total standard profile vector (TSPV), which was the mean vector of all the batch vectors of CLTs with 1.0. The nearer to 1.0 was the R or C, the higher was the similarity. The values of R and C between the TSPV and each batch vector of CLTs produced at different factories were all above 0.9150. The values of R and C between every two standard profile vectors (SPV) from different factories were all above 0.9420. A good stability and reproducibility of the CEFP of CLTs were obtained in the study. Further, we first put forward a new parameter Q to evaluate both the quantification accuracy and the qualitative accuracy for a CEFP, which was verified by determinations of GHIA, GHEA, MP and SB in CLTs. The CEFP was successfully employed to assess the quality of CLTs produced at Kunming Pharmaceutical Factory to be good.