A Development of An Analytical Spectrophotometeric Method for determination of Taurine in Energy Drinks

A novel, simple, rapid and sensitive spectrophotometric method has been developed for assay of taurine in energy drinks which is an important amino acid in body human and it is added to energy drinks to improve the mental and muscle performance. The proposed method allows selective determination of taurine in energy drinks, which are a mixture of many components such as caffeine, ginseng, vitamins, guarana, carbohydrates, colorants, preservative agents, etc. Ninhydrin was used as derivatizing agent to form an irreversible complex with taurine. The reaction of taurine with ninhydrin was completed within 20 minutes at 100˚C and the colored complex has been measured using spectrophotomer at λ_max=568 nm. The optimal conditions of this reaction have been studied. Extraction method has been developed using cation exchange resin to extract taurine and eliminate the interferences of other components in energy drinks. The validation of developed method was performed according to ICH [Q2(R1)] guidelines. A precision was estimated statistically using standard deviation (SD=0.25) and relative standard deviation (RSD%=0.64). The calibration curve was linear with a correlation coefficient (R² = 0.997). The recoveries were between [98.45-99.33] %. Then fifty samples of consumed energy drinks in Syria have been analyzed using the developed method to determine their content of taurine.