Direct Analysis in Real-time Mass Spectrometry for Rapid Identification of Traditional Chinese Medicines with Coumarins as Primary Characteristics

Abstract

Introduction: The increasing popularity of traditional Chinese medicines (TCMs) necessitates rapid and reliable methods for controlling their quality. Direct analysis in real-time mass spectrometry (DART-MS) represents a novel approach to analysing TCMs.

Objective: To develop a quick and reliable method of identifying TCMs with coumarins as primary characteristics.

Methodology: DART-MS coupled with ion trap mass spectrometry was employed to rapidly identify TCMs with coumarins as primary characteristics and to explore the ionisation mechanisms of simple coumarins, furocoumarins and pyranocoumarins in detail. With minimal sample pretreatment, mass spectra of Fraxini Cortex, Angelicae Pubescentis Radix, Peucedani Radix and Psoraleae Fructus samples were obtained within seconds. The operating parameters of the DART ion source (e.g. grid electrode voltage and ionisation gas temperature) were carefully investigated to obtain high-quality mass spectra. The mass spectra of samples and DART-MS/MS spectra of marker compounds were used to identify sample materials.

Results: Successful authentication was achieved by analysing the same materials of different origins. Some simple coumarins, furocoumarins and pyranocoumarins can be directly detected by DART-MS as marker compounds.

Conclusion: Our results demonstrated that DART-MS can provide a rapid and reliable method for the identification of TCMs containing different configurations of coumarins; the method may also be applicable to other plants. Copyright © 2016 John Wiley & Sons, Ltd.

Keywords: DART-MS; coumarin; identification; traditional Chinese medicine.