Determination of 4 Organophosphorous Herbicides Residues in Grape Wine by HPLC-MS/MS

HPLC-MS/MS was proposed for the determination of the residual anount of 4 organophosphorus herbicides, including paspalum, methamphoron, imphoron, and piperon in grape wine. 2.000 0 g of samples were mixed with 12 mL of ethyl acetate and 1.00 g of sodium chloride by vertical oscillation for 30 s, and the solution was extracted ultrasonically for 10 min. The extract was purified with N-propyl ethylenediamine (1.00 g) and anhydrous magnesium sulfate (0.20 g) by dispersive solid phase extraction. The purified solution was then separated on ZORBAX XDB-C₁₈ column as stationary phase and the mixture of 0.1% (φ) formic acid solution and methanol with the volume ratio of 15 to 85 was used as mobile phase in isocratic elution. ESI⁺ and MRM were adopted in MS analysis, and external standard method was used for quantification. Linearity relationships between values of peak area and mass concentration of 4 organophosphorus herbicides were kept in the same range of 1.0-200.0 μg·L^-1, with detection limits (3S/N) in the range of 0.01-0.04 μg·kg^-1. Test for recovery was made by standard addition at 3 different concentration levels, giving results in the range of 69.3%-99.2%, with RSDs of determined values (n=5) ranged from 2.3% to 8.1%.