Detection of macrocyclic lactones in porcine liver,meat and fish tissue using LC–APCI–MS–MS

A selective and sensitive method for the simultaneous determination of five avermectins (abamectin, ivermectin, doramectin, emamectin and eprinomectin) and one milbemycin (moxidectin) in porcine liver, bovine meat and fish tissue was developed. The method involved extraction with acetonitrile and purification by C₁₈ solid-phase extraction. Detection was carried out using liquid chromatography coupled to multiple mass spectrometry (LC–MS²) equipped with APCI in the negative mode. This method was validated according to the requirements of Commission Decision EC/2002/657 (Implementing Council Directive 96/23/EC concerning the performance of analytical methods and the interpretation of results. Off J Eur Commun. L221: 8–36.). In addition to the linear response (R ² between 59 and 97%), good repeatability (CV between 20 and 35%), reproducibility (CV between 20 and 35%) and detection (CCα) and quantification (CCβ) limits were obtained for all compounds in all matrices considered.     

Validation of an optical surface plasmon resonance biosensor assay for screening (fluoro)quinolones in egg,fish and poultry

A surface plasmon resonance biosensor immunoassay has been developed for multi-residue determination of 13 (fluoro)quinolone antibiotics in poultry meat, eggs and fish. The following performance characteristics were determined according to the guidelines laid down for screening assay validation in European Decision 2002/657/EC: detection capability, specificity/selectivity, decision limit, repeatability, ruggedness and stability. The detection capability estimated for norfloxacin, the reference fluoroquinolone, was below 0.5, 1 and 1.5 ng g^?1 for poultry meat, egg and fish, respectively. The screening assay proved specific and showed satisfactory sensitivity below the MRL levels even though flumequine and oxolinic acid had lower cross-reactivities. A wide range of non-MRL substances were also detected at concentrations below 10 ng g^?1. Repeatability was good with both intra- and inter-assay coefficients of variation <6%; ruggedness was also demonstrated.