Separation and Standardization of Chebulinic Acid as Quality Marker of Tibetan Medicine Terminalia Chebula

A certified reference material (CRM) of chebulinic acid has been developed according to the technical requirements of GB/T 15000—2008. The CRM of chebulinic acid was obtained using the macroporous adsorption resin and preparative high performance liquid chromatography (HPLC), from the dry ripe fruit of Terminalia chebula. Then, the purity analysis, structure identification, homogeneity and stability inspection, and cooperative certification were conducted. HPLC analysis at different detection wavelengths showed that the purity was more than 98%. Liquid chromatograph-mass spectrometry (LC-MS) analysis showed that no obvious impurity peaks were found. The structure was identified as chebulinic acid by ultraviolet spectroscopy (UV), infrared spectroscopy (IR), mass spectroscopy (MS), nuclear magnetic hydrogen spectroscopy (¹H-NMR) and nuclear magnetic carbon spectroscopy (¹³C-NMR). The results indicated that the homogeneity and stability of the CRM were good within 24 months at 4 ℃. The certified purity value of chebulinic acid was 98.08%. The expanded uncertainty was 0.50% in confidence coefficient of 95%. The CRM of chebulinic acid (GSB 11-3725-2020) can be applied for the content determination, evaluation of detection methods, detection and quality control of related products.