Abstract
A quantitative HPLC-MS method was developed for rapid and sensitive analysis of 5 tannins (gallotannins and proanthocyanidin types) and 5 monoterpene glycosides (pinane type) in 70% ethanol extract of Radix Paeoniae Alba (RPA). The total analysis time was less than 10 minutes without a loss in resolution using a short column packed with 1.8 µm porous particles, six times faster than the performance of conventional columns of 5.0 µm porous particles. This assay was fully validated with respect to precision, repeatability, and accuracy. All calibration curves showed good linear regression (r 2 > 0.9961), and recoveries of all analytes fell in the ranges of 92.0–104.1%. The developed method was successfully applied to analysis of the 10 marker compounds in 6 processed RPA products and 27 commercial samples from different pharmacies in China. The quantitative results demonstrated that samples processed in different ways and from different provinces showed varied qualities based on the contents of active components. Robustness and applicability of the method offered a rapid, sensitive, and validated method for routine analysis and quality control of this herbal medicine. Meanwhile, the LC/MS method developed here provided a more economical alternative for laboratories looking into improving separation and increasing throughput, without the need to upgrade the existing HPLC system to a special ultra fast HPLC system.
ACKNOWLEDGMENTS
The authors greatly appreciate the financial support from the key program (No. 30530870) of the National Science Foundation of China, and National Key Technologies R&D Program of China.
Notes
a y: concentration of analyte (µg/mL); x: peak area ratio (analyte peak area/IS peak area).
ND = not detected.