Determination of Gallic Acid and Caffeine in Tea Pigment by RP-HPLC / 中国药房

ABSTRACT

OBJECTIVE:To establish an RP-HPLC method for the determination of Callic acid and Caffeine in tea pigment.METHODS:The separation of sample performed on Novapak ODS column(250 mm?4.6 mm,5.4 ?m).The mobile phase consisted of acetic acid-methanol-DMF-H2O(2∶3∶35∶160) with a flow rate of 1.0 mL?min-1 and detection wavelength of 280 nm.RESULTS:The linear ranges of Callic acid and Caffeine were 8.16～81.60 ?g?mL-1 and 2.84～28.40 ?g?mL-1.The average recovery rate of Callic acid was 99.8%(RSD=0.5%,n=6) and that of Caffeine was 99.9%(RSD=0.6%,n=6).CONCLUSION:The method is rapid,sensitive and accurate,and suitable for the quality control of tea pigment.