Qualitative and quantitative analysis of the major bioactive phenolic compounds of Glechoma longituba by LC-coupled with PAD and ESI-MS detection.

A sensitive and selective method based on HPLC-PAD and Quadrupole TOF ESI-MS-MS is presented for quality control of Glechoma longituba, the major bioactive phenolic compounds of which could be quantified simultaneously. LC-ESI-MS was applied for nine fully identified compounds and another eight partially identified compounds in the plant by comparing their mass spectral data and retention times with those of selected standards and literature data. For quantitative analysis, the chromatographic conditions and extraction procedure were optimized in order to ensure the exhaustive extraction of the plant material. The calibration curves for determination of the nine compounds showed good linearity over the tested ranges (r2 > 0.999). Measurement of intra-day and inter-day variability was conducted to assess precision of the method, and their RSDs were between 2.22%-2.92% and 1.35%-2.95%. The RSDs of repeatability and stability were between 0.90%-2.53% and 1.73%-2.94%. The recoveries of the nine compounds were between 94.7%-106.5%, with RSD value ranging from 0.56%-2.88%. These validation results demonstrated the suitability of the method for the precise and accurate determination of the main constituents of G. longituba. The method was used for the quality evaluation of twenty batches of G. longituba obtained from different regions of China. The multi-index comprehensive evaluation method for the different kinds of compounds can ensure the efficacy and safety of the traditional Chinese medicine.