Development of A method with liquid chromatography - tandem mass spectrometry for analysis of caffeine in wastewater

Waste water based epidemiological (WBE) approach is an analysis of wastewater chemicals exposed and consumed by population and access all population data. Since the consumption of caffeine goes back to ancient times and the popularity of coffee (main source of caffeine) that gradually increases makes possible come across caffeine and its metabolites in wastewater. In addition, stability of caffeine and to indicate only human activities make caffeine significant biomarker for wastewater based epidemiological analyses. Human biomarkers provide us information about population size and Dynamics in WBE based studies. Also, because of being an anthropogenic marker, caffeine indicate contamination on surface waters. Therefore, it is important developing a fast and reliable caffeine method. In this study it is aimed to create and validate a fast and reliable method with low quantification limit and which does not require any verification by LC-MS/MS which has been used recetly. LC-MS/MS parameters and flow program set up and validation parameters such as selectivitiy, analytical sensivity, limit of detection and determination, linearity, accuracy and robustness were studied. Limit of detection was calculated 200 ng/L, limit of quantitation was calculated 500 ng/L. Accuracy studies with 0,997 were performed in the linear range of 500-100000 ng/L. In all studies %RSD was <10; recoveries were found between %87 and %109 in different days and at different concentrations studies. In this method which requires pretreatment, tap water samples were enriched with a concentrations of 50000 ng/L and extracted. The efficiency of extractions was found %93,34 on average. In this developed method, by analysis of caffeine in wastewater, population size and dynamics of the region can be evaluated and level of pollution in surfacewater can also be evaluated whether there is a environmental risk.