BACKGROUND: The analytical method was established for determination of fungicide chinomethionat in several animal commodities using gas chromatography (GC) coupled with electron capture detector (ECD).
METHODS AND RESULTS: In order to verify the applicability of the method were optimized for determining chinomethionat in various Livestock products. Sample including beef, pork, chicken, milk, and eggs. Chinomethionat residual was extracted using acetone/dichloromethane(9/1, v/v) as extraction solvent with magnesium sulfate and sodium chloride.(salting out-associate liquid-liquid extraction) The extract was diluted with directly partitioned into dichloromethane to remove polar co-extractives in the aqueous phase. The extract was finally purified by optimized silica gel 10 g.
CONCLUSION: The Method limit of quantitation (MLOQ) was 0.02 mg/kg, considering the maximum residue level (MRL) of chinomathionate as 0.05 mg/kg in livestock product. Recovery tests were carried out at two levels of concentration (MLOQ, 10 MLOQ) and resulted in good recoveries (84.8~103.0%). Good reproducibilities were obtained(Coefficient of variation <5.2 %), and the linearity of calibration curves were reasonable (r2>0.995) in the range of 0.01-0.2 μg/mL. This established analytical method was fully validated and could be useful for quantification of chinomathionat in animal commodities as official analytical method.