Identification of Rubiae Radix et Rhizoma and Its Adulterants Based on “Mass Spectrometry Matrix”

<i>Galium elegans</i> Wall. in Roxb. (GWR) and <i>Rubia tibetica</i> Hook. f. (RTH) are common adulterants of rubiae radix et rhizoma (RRR). To strengthen RRR adulteration regulation, this paper conducted the adulteration analysis of RRR according to the "mass spectrometry (MS) matrix". Ultra-high-performance liquid chromatography-quadrupole time-of-flight-full information tandem MS expression analyzed the GWR, RTH, and RRR to obtain quantized data. The ionic intersections were extracted from different batches of the same herbs as their "ionic representation", respectively. Then, the ionic matrix of each herb relative to each other was screened out, and the top-<i>n</i> ions were regarded as the "MS matrix" of the three herbs. The "MS matrix" was used for matching test samples to obtain a credibility index. On the other hand, chemometrics was used to validate. RRR adulteration can be realized according to the "MS matrix". Note that, 3% adulterants can still be identified and three market samples were identified as adulterants. Further research proved that the adulteration identification based on the "MS matrix" of RRR, RTH and GWR is reasonable and reliable. The RRR adulteration analysis can be realized according to the "MS matrix". The "MS matrix" has certain proprietary and has an important reference for RRR adulteration regulation.