Determination of fluoroquinolones in chicken tissues by LC-coupled electrospray ionisation and atmospheric pressure chemical ionisation

The aim of this work was to develop a method for determining seven quinolones (ciprofloxacin, danofloxacin, enrofloxacin, sarafloxacin, difloxacin, oxolinic acid and flumequine) in chicken muscle by LC coupled to MS. Two ionisation techniques, ESI and atmospheric pressure chemical ionisation (APCI) were compared using standard solutions. LOD and LOQ were determined under the optimised conditions for the two sources. The ESI was found the best for the purpose. The optimised method (LC-ESI-MS) was validated for the simultaneous analysis of the quinolones regulated by European Community in spiked chicken tissues, using norfloxacin as internal standard. Recoveries obtained varied in the range 60-109%. This method was compared with LC-UV method established previously.