Electrochemical-based Quantitative Fingerprint Evaluation Strategy Combined with Multi-Markers Assay by Monolinear Method for Quality Control of Herbal Medicine.

Background: Improving the quality control (QC) criterion of herbal medicine (HM) is an ongoing challenge. A rapid and convenient electrochemical analysis technique is now emerging as a promising application for HM QC. So far, extraction and analysis of the overall electmactive components is a key issue need to be solved to improve its application in integral HM QC. Purpose: In this work, using compound liquorice tablets (CLQTs) as an example, we like to put forward a more reliable and accurate quantification method of multi-components for the precise QC of HM. Furthermore, we propose an electrochemical fingerprint-based data mining, extract and synthesis strategy for in-depth and comprehensive QC of HM, qualitatively and quantitatively. Methods and design: Firstly, the electrochemical quantitative fingerprint of 54 batches of CLQTs from nine manufacturers were developed using B-Z oscillatory system. Secondly, eight characteristic parameters were recorded and compared among samples using intuitive information and PCA. Then, t(und) was used to establish the correlation with sample dosage for determination of the relative content of overall electroactive components (Rc). The quantitative determination of five quality markers (Q-markers) were also performed using the novel method, called multi-markers assay by monolinear method (MAML). Finally, after using area integral calculus for electrochemical fingerprint, average linear quantitative fingerprint method (ALQFM) was successfully proposed to extract all latent characteristics for integral quality evaluation of samples. Results: The t(und) and dosage showed a good correlation, by which the obtained Rc displayed different fluctuation among nine manufacturers. Moreover, the contents of five Q-markers obtained by MAML displayed no significant difference with the traditional quantification method. Samples evaluated by ALQFM manifested the integral information and were divided into eight quality grades. The deduced results of correlation between P-1 with P-5C, Rc and P-A were more persuasive for demonstrating the reliability and integrity of ALQFM in quality evaluation of HM electrochemical fingerprint. Conclusion: The study confirmed the idea that quantification of Q-markers combined electrochemical-based quality evaluation strategy could be used as a reliable method for HM QC qualitatively and quantitatively from point (precise) to face (integral).