Flow analysis-solid phase extraction system and UHPLC-MS/MS analytical methodology for the determination of antiviral drugs in surface water

An automated flow analysis-solid phase extraction (FA-SPE) system and methodology of ultra-high-performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS) analysis were developed for the determination of selected antiviral drugs (acyclovir, amantadine, rimantadine, and oseltamivir) in water samples. The proposed FA-SPE approach enables the integration of various extraction stages and elimination of the sample evaporation step and offers individual customisation of SPE parameters, inter alia sample, and eluate flow rate and volume. Using the developed FA-SPE procedure, e.g. a 100-fold preconcentration of the target analytes in 1 h was achieved. A method for chromatographic analysis was also developed to determine the selected antiviral drugs in combination with the use of the FA-SPE system. The developed FA-SPE UHPLC-MS/MS method was validated including the determination of linearity of analytical graphs, limits of detection (5.5-99.9 pg mL