Determination of quinolones in chicken tissues by liquid chromatography with ultraviolet absorbance detection.
ABSTRACT This paper presents an analytical method for the determination of quinolones in chicken tissues. The procedure involves pre-treatment by solid-phase extraction (SPE) and subsequent liquid chromatography (LC) with UV absorbance detection. Different SPE disposable cartridges and extractants of the tissue samples were tested, and various columns were systematically tested. The mobile phase was composed of acetonitrile and citric buffer at pH 4.5, with an initial composition of acetonitrile-water (12:88, v/v) and using linear gradient elution. Recoveries were 66-91% in the concentration range 30-300 microg kg(-1). The detector response was linear in this range. The limits of detection were 16-30 microg kg(-1). These values were lower than the maximum residue limits established by the European Union.
Article: Enzyme-linked immunosorbent assay and colloidal gold-based immunochromatographic assay for several (fluoro)quinolones in milk[show abstract] [hide abstract]
ABSTRACT: We have developed a heterologous direct competitive enzyme-linked immunosorbent assay (ELISA) and a visual colloidal gold-based immunochromatographic assay (CGIA) for simultaneous determination of ofloxacin, marbofloxacin, and fleroxacin residues in milk using polyclonal antibodies. The half-maximum inhibition concentrations (IC50) of ofloxacin, marbofloxacin, fleroxacin, and limits of detection (LODs; calculated as IC15 values) are between 0.20 and 0.53ng mL−1, and between 0.02 and 0.05ng mL−1, respectively. The average recoveries range from of 78% to 113%, and the coefficients of variation of intra- and inter-assays are between 2 and 11%, and 3 to 19%, respectively. The LODs for ofloxacin, marbofloxacin, fleroxacin in milk are between 3.5 and 8.9ng mL−1. The visual minimum detection limit of the optimized CGIA is 2ng mL−1 for milk samples. The detection process can be completed within 10min. The strips can be stored at 4°C for 8weeks without significant loss of activity. The results of the analysis of spiked samples showed that the CGIA can be applied to preliminary, fast, and on-site screening of milk samples. The ELISA and CGIA allow for a rapid, sensitive, and low-cost determination of (fluoro)quinolones residues in milk samples. FigureA direct competitive enzyme-linked immunosorbent assay (ELISA) and a visual colloidal gold-based immunochromatographic assay (CGIA) are proposed for simultaneous determination of ofloxacin, marbofloxacin, and fleroxacin residues in milk using polyclonal antibodies Keywords(Fluoro)quinolones–Residue–ELISA–CGIA–MilkMicrochimica Acta 04/2012; 173(3):307-316. · 3.03 Impact Factor