Study on quality control of Zuojin pill by HPLC fingerprint with quantitative analysis of multi-components by single marker method and antioxidant activity analysis

Current quality control methods for Zuojin Pill (ZJP) lack comprehensiveness and practicability. This study aimed to develop a comprehensive strategy for the quality evaluation of ZJP and the prediction of potential bioactive components in ZJP. First, an HPLC method with excellent separation of main components was developed and was used to establish the chromatographic fingerprint of ZJP. Similarities were calculated by comparing 28 batches of ZJPs with the reference fingerprint and the resulting similarity values were all greater than 0.976. The 28 samples were classified into different groups according to their origins by Hierarchical Cluster Analysis, Principal component analysis, and orthogonal partial least squares discriminant analysis. Based on the classification, eight quality markers (Q-Markers) affecting the quality of ZJP were discovered. Then, using berberine as an internal standard substance, quantitative analysis of multi-components by single marker method (QAMS) for the determination of eight Q-markers was developed. The results showed that there was no significant difference between QAMS and external standard method (P＞0.05). Finally, using an off-line antioxidant system and partial least-squares model (PLS), the fingerprint-efficacy relationship of ZJP was constructed to explore and predict the bioactive components in ZJP. The present study strategy could be also applied to comprehensive quality study of other TCMs.