Chinese medicines are very complex chemical system. Especially, Chinese herbal formulae containing a variety of herbal medicines, they self-organize into an interactive and indivisible whole, and act harmoniously to treat diseases through a multi-components, multi-sites and multi-functions mode. The conventional quality evaluation approaches mainly target known ingredients or detectable components, but ignore their holistic nature. Therefore, the identification of chemical markers that can comprehensively reflect the main therapeutic effects and potential toxic activities of herbs is crucial to scientific quality evaluation of Chinese medicines.
Recently, some innovative strategies and new techniques, including multi-dimensional chromatographic techniques (2D-LC, 2D-LC/MS), high-resolution mass spectrometry based untargeted chemomics, artificial neural network based chemometrics, label-free proteomics and metabolomics have been developed in our group for quality evaluation of Chinese medicines. For example, using some of these integrated approaches, we have successfully discovered the Q-markers from Jinqi Jiangtang preparation against type 2 diabetes, and revealed the protective role of other herbs in An-Gong-Niu-Huang Wan against the hepatorenal toxicity of cinnabar and realgar.
Chinese medicines might be contaminated by some exogenous harmful residues such as heavy metals, pesticides, and mycotoxins. Traditionally, these contaminants can be detected using large-scale lab equipment such as HPLC, GC, LC-MS, GC-MS and ICP-MS. These techniques require qualified personnel, expensive instruments and complicated sample preparation, which limit their usage in production, storage, and distribution process of Chinese medicines. Therefore, research and development of simple, fast, and on-site detection methods for monitoring the levels of contaminants in Chinese medicines is extremely critical for assurance of human health.
Recently, we have developed several universal sensing techniques or platforms to detect pesticide residues using novel materials, including: 1) Fluorescence method based on nanozyme and carbon dots; 2) Smartphone-based colorimetric method; 3) Electrochemical method based on bi-functional nanozyme; 4) Ratiometric fluorescence method based on metal nanoclusters; 5) Surface-enhanced Raman spectroscopy technique. Moreover, we have also developed the luminescent metal-organic frameworks (MOFs) and fluorescent covalent organic frameworks (COFs) materials and carbon dots based fluorescent immunoassay for the detection of heavy metal ions and mycotoxins, respectively.