Centrifugal Extraction and Determination of Caffeine in Tea Drink by UV-Vis Spectrophotometry

The UV-Vis method for detecting caffeine in tea drink at 276 nm after centrifugal extraction was established.The results showed that the absorbence(A) showed a good linear relation with concentration of caffeine(C) from 5.324 mg/L to 16.940 mg/L.The correlation coefficient was 0.999 5 and the recovery ranged from 97.6% to 99.4%.In conclusion,the method was suitable for rapid determination of caffeine in tea drink.