Determination of a series of quinolone antibiotic using liquid chromatography-mass-spectrometry

The aim of this work was to develop a method of characterization and determination of ten quinolones by liquid chromatography (LC) coupled to pneumatically assisted electrospray ionization (ESI) mass spectrometry (MS). For this purpose, the operational parameters of LC-ESI-MS were optimized in order to obtain suitable separations and high sensitivity of the greatest number of quinolones. In the established method, the mobile phase is composed of acetonitrile and acetate-formiate buffer at pH 2.5, with an initial composition of 18:82 by volume of acetonitrile-water, and using a linear gradient elution. Quality parameters were determined and satisfactory results were obtained. Likewise, the method detection limit was about 10-ng(.)mL(-1) for most of the quinolones studied employing selected-ion monitoring mode and using an internal standard. The method was specific and reproducible. Thus, the proposed methodology can be applied for control of these compounds in animal products commonly consumed in the human diet.