Determination of imidocarb in animal biosamples using simple high-performance liquid chromatography with diode-array detection.

The aim of this study was to develop an analytical method for detection of imidocarb [1,3-bis[3-(4,5-dihydro-1h-imidazol-2-yl)phenyl]urea] in beef and milk using high-performance liquid chromatography (HPLC) with diode-array detection (DAD). Imidocarb was separated on a reversed-phase column (4.6×250 mm, 5 μm) with a mobile phase consisting of 85:15 (v/v) 0.1% trifluoroacetic acid/acetonitrile. The flow rate was 1 ml/min, and the column temperature was maintained at 20°C. Detection was carried out at 260 nm using a DAD detector. The analytical samples were extracted using a solid-phase extraction (SPE) method. The calibration curves showed good linearity (r≥0.998). Limits of quantifications (LOQs) were 0.15 mg/kg in beef and 0.025 mg/kg in milk. Intra- and inter-day precisions were 3.2-6.1 and 1.4-6.9%, respectively, and the accuracy (recovery) was 80.4-82.2% and 80.1-89.5% in beef and milk, respectively. Thus, an analytical protocol using SPE extraction followed by HPLC with DAD was successfully developed, which demonstrated acceptable precision and recovery.