Multi-responses extraction optimization based on response surface methodology combined with polarity switching HPLC–MS/MS for the simultaneous quantitation of 11 compounds in Cortex Fraxini: Application to four species of Cortex Fraxini and its 3 confusable species

A novel polarity switching high performance liquid chromatography–electrospray ionization tandem mass spectrometry (HPLC–ESI-MS/MS) approach combining optimization of extraction condition by response surface methodology (RSM) was developed for the simultaneous quantitative analysis of 11 compounds in Cortex Fraxini, a commonly used traditional Chinese medicine. The ultrasonic extraction conditions of the 11 analytes including sample quantity,...