Quantifying caffeine content in green tea and soft drink using UV-visible spectrophotometry

To find out how much caffeine is in the soft drink (Sting) and green tea (Tetley). which, with the aid of a UV-visible spectrophotometer, are commercially available in the neighborhood market. Using chloroform as an extractant, the caffeine was extracted from them, and the UV-Visible spectrophotometer was used to measure it both quantitatively and qualitatively. At 276nm, caffeine in chloroform is most absorbable. A standard solution of caffeine ranging from 2 to 30 parts per million was generated using chloroform, and the calibration curve indicates linearity with a correlation coefficient of 0.99. Research shows the caffeine content in Tetley is 0.4% (15mg/250g) and sting is 2.5% (72mg/250ml) which is in range of promising limit by the company Tetley (i.e.,0.6%) and Sting (i.e. 2.88%).