Validation Of Analytical Methods For The Determination Of Imidocarb In Tissues And Milk Of Cattle, Sheep And Goats

In accordance with the Guidelines on Validation of Analytical Procedures suggested by the European Agency for the Evaluation of Medicinal Products (EMEA), three methods were used to assess and validate the most suitable procedure to analyse residual imidocarb concentrations in edible tissues and milk of cows, sheep and goats. Based on the criteria selected to identify the most suitable analytical method, the best performances were obtained using a hexane/isoamyl alcohol liquid-liquid extraction procedure for sheep milk; after exposing the matrices to enzymatic digestion before extraction, the same method was used for the muscle, liver, kidney and fat of sheep and goats and for goat milk; and an acetone/chloroform liquid-liquid extraction method was used for all the matrices of cows. The selected methods fulfil the validation criteria recommended by the EU authorities. The total recovery ranged from 70.1% (sheep liver) to 90.8% (cattle muscle). The accuracy of the recoveries was always <30% and the precision of the different methods was always <15% for intra-assay precision and <16% for inter-assay precision. The results obtained show that different matrices and animal species have different extraction requirements, which stresses the importance of validating routine analytical methods for appropriate combinations of species and tissues.