GC-MS Determination of Residual Clofentezine in Fruits

Clofentezine in fruit sample was extracted with acetone and water mixed in the ratio of 4 to 1,and then partitioned with dichloromethane.The analyte in dichloromethane was purified by passing successively through gel-chromatographic column and Florisil solid phase extraction (SPE) column.The eluate from the Florisil SPE column was evaporated to dryness in a water bath at 40 ℃.The residue was taken up with acetone and made up to 2.00 mL with acetone,which was used for GC-MS determination,with external standard method.Detection limit of the method was found to be 0.010 mg·kg-1.Recovery test was made by standard addition method,and values of recovery obtained were in the range from 83.8% to 91.6%.Test for precision was performed at 3 different concentration level,giving values of RSD′s (n=10) in the range of 5.1%-7.4%.