Analysis of Phoxim Residue in Animal Food Production (Cattle and Pig) by LC/ESI-MS/MS

Phoxim, which is one of veterinary drugs, is a well-known antiparasitic agent in wide use. In this paper, phoxim was extracted from cattle and pig tissue using solid-phase extraction (SPE) employing a silica cartridge with acetonitrile. Liquid chromatography/electrospray ionization-tandem mass spectrometry (LC/ESI-MS/MS) for the analysis of phoxim from animal tissue was presented. Phoxim was detected on a C18 column (2.1x100 mm, 3.5 mu m) using a mobile phase of 0.1% formic acid in water and acetonitrile. A linear correlation observed in the calibration curves for cattle (0.0048 similar to 2.0 mg/kg) and pig (0.0055 similar to 2.0 mg/kg) showed above r 2 = 0.995. Accuracy measured at concentrations ranging from 0.0048 to 0.2 mg/kg was the range of 68.2 similar to 106.9%. Limit of detection (LOD) and limit of quantitation (LOQ) were the range of 0.0014 similar to 0.0017 mg/kg and 0.0048 similar to 0.0055 mg/kg, respectively. The precision (RSD%) was below 11.2%.