[Quantification of caffeine from energy drinks with mass spectrometry method (LC/MS)]

A high performance liquid chromatography coupled with mass spectrometry method (LC/MS) for quantification of caffeine from energy drinks was elaborated. It was utilised a Zorbax SB-C18, 100 mm x 3.0 mm i.d., 3.5 microm column with a mobile phase containing methanol/ solution 0.2% formic acid in water. Detection and quantification of caffeine was based on monitoring the protonated molecular ion abundance (m/z 194.9). The quantification was made using the external standard method. The calibration curve were made on range 0.26-26 microg/ml for caffeine with a correlation coefficient greater than 0.995. There were analysed 12 energy drinks with a caffeine content between 13 and 34 mg/100 ml.