Multiresidue analysis of quinolones in water by ultra-high perfomance liquid chromatography with tandem mass spectrometry using a simple and effective sample treatment.

A rapid and simple analytical method has been developed for the determination of 19 quinolones in environmental water samples using ultra high performance liquid chromatography with tandem mass spectrometry. Chromatographic and detection conditions have been optimized and the separation was achieved in less than 4 min. The separation was carried out using a new-generation column filled with superficially porous particles, resulting in lower backpressure and better resolution than totally porous particle columns. The quinolones were detected by electrospray ionization in positive mode using multiple-reaction monitoring mode for acquisition. A sample treatment based on liquid-liquid extraction and phase separation via salting-out was employed to achieve a fast and simple extraction that enables the multiresidue analysis. The method has been validated for an environmental well water sample from a mountain area. Very low limits of detection (between 10 and 90 ng/L) with relative standard deviations lower than 16.5% and recoveries higher than 73% were achieved. Moreover, well waters from different origins (mountain and coast areas and irrigated land) have been evaluated and similar results were obtained.