LC-MS/MS Determination of Residual Amounts of 10 Herbicides in Sugarcane

The pretreated sugarcane sample (2.00 g) was homogeneously extracted with 10.0 mL acetonitrile and purified by QuEchERS method. In LC separation Hypersil Gold chromatographic column was used as stationary phase, and mixtures of 10 mmol·L^-1 ammonium acetate solution containing 0.1% (φ) formic acid and acetonitrile mixed in different ratio were used as mobile phase in gradient elution. ESI⁺ and selective reaction monitoring were adopted in MS/MS. Linear relationships between values of peak area and mass concentration of the 10 herbicides were kept in the same range of 10-1 000 μg·L^-1, with lower limits of determination (10S/N) in the range of 2-10 μg·kg^-1. On the base of blank sample, test for recovery was made by standard addition method; values of recovery found were in the range of 82.3%-120%, with RSDs (n=6) in the range of 3.9%-8.2%.