Abstract
BACKGROUND: Rubia schumanniana E. Pritz. (RSP) and Rubia magna P. G. Xiao (RMP) are common adulterants of Rubiae radix et rhizoma (RRR). To realize RRR adulteration analysis, this paper conducted an identification evaluation of RRR based on liquid chromatography-mass spectrometry (LC-MS). METHODS: After LC-MS analysis and data conversion, the ion intersections were taken from different batches of RSP, RMP, and RRR. Then, the proprietary ions of three herbs were obtained by taking the de-intersection. Finally, the top-n ions were treated as the "ion identity" of RSP, RMP, and RRR for matching test samples to obtain the recognition index (RI) and combined chemometrics for analysis. RESULTS: The identification evaluation of RRR can be realized based on the "ion identity", even if 3% RSP (or RMP) in RRR samples can still be recognized. Combined with chemometric analysis, three market samples were identified as adulterants, proving that identification evaluation based on "ion identity" is reasonable. CONCLUSIONS: The "ion identity" based on LC-MS, which helps in realizing RRR identification evaluation. It has important reference significance for RRR analysis.