Rapid Determination of Six Tannins in Chinese Medicinal Materials Based on UPLC-MS/MS

OBJECTIVE To develop an UPLC-MS/MS method for rapidly qualitative and quantitative determination of six tannins(gallic acid, methyl gallate, ethyl gallate, ellagic acid, 3,3'-Di-O-methylellagic acid, coriagin) in Chinese medicinal materials. METHODS An Agilent RRHD Eclipse Plus C₁₈ column(2.1 mm×50 mm, 1.8 μm) with a gradient elution of methanol and 0.1%formic acid in water at a flow rate of 0.3 mL·min^-1, the column temperature was 40℃, and the injection volume was 1 μL. Triple quadrupole mass spectrometry with electrospray ion source and negative ion mode was used to quantitatively analyze 6 tannins in 15 kinds of Chinese herbal medicines by multiple reaction monitoring mode. RESULTS Good linear relationship(r>0.999) were observed in the test ranges for 6 compounds, and the average recoveries of gallic acid, methyl gallate, ethyl gallate, ellagic acid, 3,3'-Di-O-methylellagic acid, coriagin were 99.8%(RSD=1.11%), 98.3%(RSD=2.23%), 100.1%(RSD=1.07%), 100.3%(RSD=1.34%), 100.7%(RSD=1.64%), 99.2%(RSD=1.24%), respectively. The gallic acid and ethyl gallate were detected in all 15 kinds of Chinese medicinal materials, and the content in Chinese gallnut was the maximum; the content of ellagic acid in Rubi Radix et Rhizoma was the highest; another 3 compounds were distributed in above drugs non-uniformly. CONCLUSION The established method is stable, rapid, sensitive, it can be used for the quantitative analysis of above six tannins in Chinese medicinal materials.