RESUMEN
A HPLC-UV-ELSD method was established for simultaneous determination of six components in two intermediates of Shenqi Fuzheng injection (SFI) and the feasibility of establishing quantitative analysis of multi-components by single marker (QAMS) methods on different detectors was further explored. Calycosin-7-O-β-D-glucoside and astragloside Ⅳ were selected as internal reference substances for respectively flavonoids and saponins, and relative correlation factors (RCF) of formononetin-7-O-β-D-glucoside, 9, 10-dimethoxypterocarpan-3-O-β-D-glucopyranoside, 2'-dihydroxy-3', 4'-dimethoxyisoflavan-7-O-β-D-glucopyranoside and astragloside Ⅱ were calculated. Eventually, quantitative results of the 14 samples were compared between QAMS and external standard method. The sample concentrations calculated by QAMS were similar with concentrations calculated by external standard method, and the absolute values of relative deviations were generally less than 5% according to the UV detection of flavonoids. On the basis of ELSD detection for saponins, however, the absolute values of relative deviation of the two methods ranged from 0.48% to 23.17%. The QAMS method built on ultraviolet (UV) detectors was stable and can be used as a substitute method to reduce the consumption of standard compounds; meanwhile, the accuracy of QAMS method built on evaporative light scattering detector (ELSD) was inferior to that of external standard method, and the working principle of ELSD and feasible concentration range remain to be further studied.
RESUMEN
Design space approach is applied in this study to enhance the robustness of first ethanol precipitation process of Codonopsis Radix (Dangshen) by optimizing parameters. Total flavonoid recovery, dry matter removal, and pigment removal were defined as the process critical quality attributes (CQAs). Plackett-Burman designed experiments were carried out to find the critical process parameters (CPPs). Dry matter content of concentrated extract (DMCE), mass ratio of ethanol to concentrated extract (E/C ratio) and concentration of ethanol (CEA) were identified as the CPPs. Box-Behnken designed experiments were performed to establish the quantitative models between CPPs and CQAs. Probability based design space was obtained and verified using Monte-Carlo simulation method. According to the verification results, the robustness of first ethanol precipitation process of Dangshen can be guaranteed by operating within the design space parameters. Recommended normal operation space are as follows: dry matter content of concentrated extract of 45.0% - 48.0%, E/C ratio of 2.48-2.80 g x g(-1), and the concentration of ethanol of 92.0% - 92.7%.