A Novel Strategy using Single Standards to Determine Multi-components in order to Quantify the Major Macrocyclin Diterpenoids and Triterpenes in the Roots of Euphobia kansui

It was hardly practical to control the quality of Chinese herbal medicines with different types of constituents, broad polarities, and a variety of UV absorptions utilizing a single standard to determine multi-components (SSDMC) method alone. To extend the application range of the SSDMC method, a new strategy was developed and named as WP-ERS-CSP-SSDMC. This new strategy combined three different techniques, namely wavelength program (WP), exogenous reference standard (ERS) and core-shell particle (CSP), to enhance the existing SSDMC method. Taking Kansui Radix (roots of Euphobia kansui) as an example, thirteen major components including three jatrophane diterpenoids, eight ingenane diterpenoids and two triterpenes which included three pairs of isomerides and three strong hydrophobic components were all simultaneously assayed using this new strategy with ethyl benzoate, a synthetic compound, employed as a single reference standard for the first time. A C8 column packed with 2.7 µm core-shell particles was optimized to separate these constituents in 25 minutes on a conventional HPLC instrument with a photodiode array detector on which a four-stage wavelength program was established. The WP-ERS-CSP-SSDMC method was validated to have the capacity to acquire more repeatable and consistent results than that obtained by traditional external standard methods. Through Plackett-Burmantest (PB) tests, eight primary chromatographic parameters of the method were investigated and it was found that the two factors, wavelength and flow rate, should be strictly restrained. At last 75 batches of Kansui Radix and its three different processing products were successfully analyzed and discriminated by applying the proposed method. This work provided a useful strategy for SSDMC method making the simultaneous multi-component assay of complex TCM system achievable, and an extensive application of multi-component quality control of TCM feasible.