Simultaneous quantification of flavonoids and phenolic acids in Herba Scutellariae barbatae and its confused plants by high performance liquid chromatography-tandem mass spectrometry.

A sensitive and selective high performance liquid chromatography-tandem mass spectrometric method (HPLC-MS/MS) has been developed for simultaneous analysis of 11 components (7 flavonoids and 4 phenolic acids) in Herba Scutellariae barbatae. Simultaneous separation of these 11 compounds was achieved on a C18 analytical column with gradient elution of methanol and 0.1‰ acetic acid (v/v) at a flow rate of 0.8mL/min. The precursor and product ions of analytes were monitored on a hybrid quadrupole linear ion trap mass spectrometer equipped with a turbo ion spray interface in negative mode using multiple-reaction monitoring (MRM). Full validation of the assay was carried out including linearity, precision, accuracy, limits of detection and quantification. The results demonstrated that the method developed was reliable, rapid and specific. Then the method was successfully applied to differentiate 18 batches of Herba Scutellariae barbatae samples and 3 batches of its confused plants from different sources.