Study on HPLC digital fingerprint of Coptidis Rhizoma and content determination of seven alkaloids

To establish an HPLC digital fingerprint for Rhizoma Coptidis produced in E'mei, and apply it in the determination of Rhizoma Coptidis herbs produced in main producing areas nationwide, while determining the content of seven quaternary ammonium alkaloids contained in Coptidis Rhizoma, in order to provide basis for scientific evaluation and effective control over quality of Rhizoma Coptidis. Diamonsil C18 column (4.6 mm x 250 mm, 5 microm) was adopted and eluted with acetonitrile 0.025 mol x L(-1) KH2PO4 solution (adjust pH to 3.0 with H3PO4) (40:60) containing SDS 1.7 g x L(-1). The flow rate was 1.2 mL x min(-1), the detective wavelength was 345 nm, and the column temperature was 40 degrees C. The chromatographic fingerprint similarity evaluation system for traditional Chinese medicines (state pharmacopeia committee of China) was used for analysis. The chromatographic fingerprint similarity of ten batches of Coptidis Rhizoma samples produced in Emei was more than 0. 99. There were altogether 10 common peaks, and eight of them were identified. A comparative analysis showed a high similarity between samples from five main producing areas nationwide and Coptidis Rhizoma herbs in E'mei. Meanwhile, the content of seven major alkaloids contained in Coptidis Rhizoma herbs, namely groenlandicine, columbamine, jatrorrhizine, epiberberine, coptisine, palmatine and berberine were determined. As the method was highly sensitive and specific, the combination of HPLC digital fingerprint and alkaloid content determination could reflect its inherent quality in an all-round way, which provided scientific basis for the quality control of Coptidis Rhizoma.