Internal-standard quantitative determination of chlorogenic acid in Eucommia ulmoides plant by CE-MS

Eucommia ulmoides is a traditional Chinese herb medicine plant and its pharmaceutical component is a secondary metabolite chemical chlorogenic acid. And it is also an important active component in many kinds of Chinese traditional medicine. Chlorogenic acid widely exists in the leaves of Eucommia ulmoides and dried buds or open flowers of Caprifoliaceae plant. The high sensitivity detection method and precise quantification pretreatment program of chlorogenic acid are important for exploring the role of the Chinese traditional medicine in curing disease, and could provide the more detection method for the study of accumulation of plant secondary metabolites. This work establishes an effective analytical method to accurately determine the chlorogenic acid content in plant samples. This method introduces the 1-Naphthaleneacetic acid (NAA) into the analysis procedure function as the internal standard to improve the determination analysis quality and use the electrophoresis-mass spectrometry to enhance the specificity and sensitivity of the detection. The standard curves of standard chemicals of NAA andchlorogenic acid were established and the R² of two curves was greater than 0.999 0. The spiked recovery of chlorogenic acid in plant samples was 93.61% and 97.43%. The method has been used to analyze the chlorogenic acid of E. ulmoides and Lonicera japonica. The content of chlorogenic acid extracted from E. ulmoides was 0.92%, and Lonicera japonica was 1.31%.