Tobolkina, ElenaQiao, LiangRoussel, ChristopheGirault, Hubert H.2014-07-092014-07-092014-07-09201410.1016/j.talanta.2014.07.024https://infoscience.epfl.ch/handle/20.500.14299/104980WOS:000341897800053Standard addition strips were prepared for the quantitative determination of caffeine in different beverages by electrostatic spray ionisation mass spectrometry (ESTASI-MS). The gist of this approach is to dry spots of caffeine solutions with different concentrations on a polymer strip, then to deposit a drop of sample mixed with an internal standard, here theobromine on each spot and to measure the mass spectrometry signals of caffeine and theobromine by ESTASI-MS. This strip approach is very convenient and provides quantitative analyses as accurate as the classical standard addition method by MS or liquid chromatography.CaffeineMass spectrometryQuantitative analysisElectrostatic spray ionizationtext::journal::journal article::research article