Establishment and Optimization of Quality Standards for the Traditional Tibetan Medicine Preparation of Liuwei Nengxiao Pills

Objective To establish quality standards for Liuwei Nengxiao pills, to optimize the quality control method, and to provide references for the quality control of Liuwei Nengxiao pills.

Methods Chebula, dried ginger, and Tibetan liqueur root in Liuwei Nengxiao pills of different batch numbers were analyzed by thin layer chromatography (TLC). Then, the content of chrysophanol in the preparation was determined by high performance liquid chromatography (HPLC). Furthermore, a series of methodological validation, including the investigation of the linear relationship, precision, stability, and reproducibility and sample recovery test, were performed to verify the reliability of the results.

Results The TLC identification method was easy to perform and demonstrated high specificity, clear spots, and good separation effect. In addition, the negative controls showed no interference. The HPLC method showed high accuracy. The results of methodological validation showed that the peak area of chrysophanol had a good linear relationship (r²=1.0) in the range of 0.06-0.80 μg, presenting good precision (with the relative standard deviation being lower than 2.0%), good stability and reproducibility (with the relative standard deviation being lower than 1.0%), and an average recovery rate of 100.8%.

Conclusion TLC and HPLC are easy to perform, showing high accuracy and reproducibility. The quality standards established are scientific, reasonable, stable, and feasible, providing references for the quality control of Liuwei Nengxiao pills.