Multiresidue determination of (fluoro)quinolone antibiotics in chicken by polymer monolith microextraction and field-amplified sample stacking procedures coupled to CE-UV

Simultaneous determination of 9 (fluoro)quinolone antibiotics (FQs) was accomplished by capillary electrophoresis-ultraviolet (CE-UV) based on poly(methacrylic acid-co-ethylene glycol dimethacrylate) (MM-EGDMA) monolith microextraction (PMME) coupled with on-line preconcentration technique of field-amplified sample stacking (FASS). The effects of composition of the acid and organic solvent in the sample solution, sampling time, and voltage on the efficiency of the sample stacking have been systematically investigated. Several parameters that influence extraction efficiency for PMME such as pH of sample solution, extraction volume, and wash and desorption conditions were optimized. In the proposed method, a substantial increase in sensitivity for all the FQs tested was achieved by the combination of PMME procedure with on-line preconcentration of FASS prior to CE analysis. Good linearities were obtained for the 9 tested FQs with the correlation coefficients (R) above 0.9954. The limits of detection (S/N=3) were found to be 2.4-34.0 ngg(-1) and the recoveries ranged from 81.2 to 100% with relative standard deviations less than 11.3%. The proposed PMME-FASS-CE method was applied to the determination of FQs residues in chicken samples. (C) 2010 Elsevier B.V. All rights reserved.