Combination of Internal Extractive Electrospray Ionization Mass Spectrometry and Statistical Analysis for High-Throughput Molecular Differentiation of Rehmannia glutinosa Samples.

(Gaert.) Libosch. ex Fisch. et Mey. is a perennial herb of the Scrophulariaceae family, which has long enjoyed a good reputation in China, and has a wide range of pharmacological effects and clinical applications. The place of origin is an important factor affecting the chemical composition of , resulting in different pharmacological effects. Herein, internal extractive electrospray ionization mass spectrometry (iEESI-MS) combined with statistical techniques was established for high-throughput molecular differentiation of different samples. Dried and processed samples from four different places of origin were analyzed by iEESI-MS with high throughput (>200 peaks) and rapidness (<2 min/sample) without sample pretreatment. Clear separation models created by OPLS-DA were then established for distinguishing the places of origin of dried and processed by using the obtained MS data. In addition, the molecular differences between the pharmacological effects of dried and processed were also investigated by OPLS-DA, and 31 different components were screened out. This work provides a promising method for evaluating the quality of traditional Chinese medicines and studying the biochemical mechanism of processing.