Rapid identification and quantitative analysis of the chemical constituents in Scutellaria indica L. by UHPLC–QTOF–MS and UHPLC–MS/MS

Abstract

Ultra high performance liquid chromatography (UHPLC) coupled with a hybrid quadrupole time-of-flight mass spectrometry (QTOF–MS) was used to separate and identify the compounds in Scutellaria indica L. Fragmentation patterns of these compounds were investigated by the UHPLC–QTOF–MS technique in both negative and positive ion modes. By using this strategy, both intact precursors and fragment ions information were obtained from a single injection. A total of 42 phenolic and other compounds were unequivocally or tentatively identified from S. indica for the first time. Among them, 8 phenolic compounds: scutellarin, luteolin, naringenin, wogonoside, apigenin, hispidulin, wogonin and chrysin were further quantified and used as marker substances by multiple-reaction monitoring in negative ionization mode. The results demonstrated that the calibration curves for all analytes showed good linearity (R2>0.9992) within the test ranges. The overall limits of detection and limits of quantification were 0.12–10.52ng/mL and 4.67–20.22ng/mL, respectively. The recovery was 96.02–102.88% with a relative standard deviation of less than 3.02%. It is proposed that the methods described here can be applied for rapid evaluation, quality control and authenticity establishment of S. indica.