SPE-LC/MS/MS method for detection of antidiabetic contaminants in municipal and rural wastewater

Abstract

Antidiabetic drugs are among the most prescribed and consumed pharmaceuticals worldwide. Their occurrence in environment was little investigated due of lack of analytical methods for their detection in waters. In this work has been developed a selective SPE-UHPLC/MS/MS method for isolation, identification and quantification of some antidiabetic compounds. The 3 selected analytes (glyburide, glimepiride and repaglinide) were separated on Eclipse C18 LC column at 30°C using isocrat elution with mobile phase of acetonitrile: 0.04% acetic acid (60/40, v/v %). The optimal flow rate was 0.2 mL/min and the injected volume was 10 µL. The contaminants were detected in negative electrospray ionization mode (ESI-) by Multiple Reaction Monitoring (MRM). Collision energy, fragmentor voltages were optimized to obtain high sensitivity. Optimization of SPE-LC-MS/MS parameters gave low quantification limit values between 0.27 and 11.1 ng/L. The organic pollutants were isolated from waste water samples on Strata C18 cartridges. The linear regressions were drawn in the interval of 1-100n g/L with good determination coefficients. Spike recovery rates were between 74.5 and 88.2% for waste water, with satisfactory precisions (RSD<15). the method was applied to analyze real influent and effluent of wastewater treatment plant (WWTP) samples.