title: Optimization of a pressurized liquid extraction method by experimental design methodologies for the determination of fluoroquinolone residues in infant foods by liquid chromatography.
abstract: In the present study, we have developed a method based on pressurized liquid extraction (PLE) and liquid chromatography with fluorescence detection (LC-FLD) for the determination of residues of fluoroquinolones (FQs) in infant food products. PLE extraction has been optimized by the application of experimental design methodologies. Initially, a fractional factorial design (FFD) was used to screen the significance of four extraction parameters: solvent composition, temperature, pressure and number of cycles. The most significant factors, identified by ANOVA analysis, were the solvent composition, temperature and pressure, which were further optimized with the aid of a face centred design (FCD) and the desirability function. The optimized operating PLE conditions were as follows: ACN/o-phosphoric acid 50mM pH 3.0 (80:20, v/v), 80 degrees C, 2000psi and three extraction cycles of 5min. Under these conditions, recoveries of the target FQs varied between 69% and 107% with RSDs below 9%. The whole method was validated according to the Commission Decision 2002/657/EC guidelines. The proposed method has been successfully applied to the analysis of different infant food products bought in local supermarkets and pharmacies. The results showed the presence of residues of enrofloxacin in a non-compliant baby food sample corresponding to a chicken-based formulation, which were also confirmed and quantified by LC-MS/MS analysis.
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, Universidad Complutense de Madrid, E-28040 Madrid, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Rodriguez
authors.forename: F Navarro
authors.initials: FN
authors.lastname: Villoslada
authors.forename: M C
authors.initials: MC
authors.lastname: Moreno-Bondi
authors.forename: M D
authors.initials: MD
authors.lastname: Marazuela
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D000704:Analysis of Variance; D005591:Chemical Fractionation / Q000379:methods*; D002853:Chromatography, Liquid / Q000379:methods*; D000077422:Enrofloxacin; D024841:Fluoroquinolones / Q000032:analysis*; D007225:Infant Food / Q000032:analysis*; D008956:Models, Chemical; D011312:Pressure; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D053719:Tandem Mass Spectrometry / Q000379:methods; D013696:Temperature
chemical_list: D000097:Acetonitriles; D024841:Fluoroquinolones; D000077422:Enrofloxacin; C032159:acetonitrile