A novel strategy to identify analytical markers of Cerebralcare Granule for quality assessment by ultra-high performance chromatography and chemometric analysis

Abstract

Selecting appropriate analytical markers of botanical drugs is a critical step in quality control. This study presents a strategy to rapidly identify analytical markers of botanical drugs via ultra-high performance chromatography coupled with a diode array detector (UPLC-PDA) and chemometric methods. Untargeted principle component analysis (PCA) and supervised orthogonal partial least squares discriminate analysis (OPLS-DA) were adopted to select key markers which contributed to batch-to-batch variations. Cerebralcare Granule (CG), a commonly used botanical drug for the treatment of cerebrovascular diseases, was employed as an example. Thirty batches of CG samples were analyzed by UPLC to generate a dataset of peak areas for PCA and OPLS-DA. Obvious clustering was observed in the OPLS-DA score plot, and candidate markers were recognized from the scatter plots and variable importance in projection values of OPLS-DA. Chemometric analysis extracted eight candidate markers, whose accurate molecular weights were assigned by liquid chromatography combined with quadrupole time-of-flight mass spectrometry. Finally, an UPLC-based method was developed and validated for simultaneous quantification of eight markers in various samples. Using this strategy, rosmarinic acid, gallic acid, chlorogenic acid, paeoniflorin, albiflorin, ferulic acid, caffeic acid and aurantio obtusifolin were rapidly identified as the analytical markers of CG. The quantitative analysis results indicated that the contents of these markers showed significant differences between the qualified and expired samples. In conclusion, the integrated use of UPLC and chemometric analysis provides a reliable approach to the identification of analytical markers for quality control of botanical drugs.