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A fast ultrahigh performance liquid chromatography (UPLC) method has been developed for simultaneous analysis of caffeine and 13 index polyphenols-gallic acid, 8 primary catechins and 4 primary theaflavins in black tea. The method was evaluated in terms of linearity, precision, accuracy and recovery. The lower limits of detection and quantification were in the range of 0.05-0.91 and 0.15-3.00 mg/L, respectively. Satisfactory linearity with correlation coefficient (R2 &gt; 0.9992), interday and intraday precision with the relative standard deviations (&lt;2.94% and &lt;5.06%, respectively), interday and intraday accuracy with relative errors (REs, -5.34% &lt; REs &lt; 4.36% and -5.36% &lt; REs &lt; 7.07%, respectively) and recovery (95.81-104.48%) were achieved for all target compounds. The UPLC method was applied for the analysis of the 14 compounds in 6 black tea samples.

A Rapid UPLC Method for Simultaneous Analysis of Caffeine and 13 Index Polyphenols in Black Tea