Simultaneous Determination of Rimsulfuron and Haloxyfop-P-Methyl and Its Metabolite Haloxyfop in Tobacco Leaf by LC-MS/MS.

Background : Tobacco ( Nicotiana tabacum L .), is an important economic crop. In China, the use of rimsulfuron and haloxyfop-P-methyl herbicides for weed management during the planting period is necessary to improve the production of tobacco. Objective : To establish and validate a quick, easy, cheap, effective, rugged, and safe LC-MS/MS method to determine rimsulfuron, haloxyfop-P-methyl, and haloxyfop in tobacco leaf samples. Methods : We optimized MS/MS conditions and chromatographic conditions for optimal detection conditions. The extraction solvent and sorbent were optimized, and the analysis of variance was applied to analyze the pretreatment method to obtain the optimal pretreatment conditions. Results : The validation results showed that the proposed method exhibited good linearity (R² > 0.9978), satisfactory recovery (72.51-101.60%) and low LOQ (0.02-1.00 mg/kg). The matrix effects of the three analytes in the two tobacco leaf matrixes were different. The dissipation results showed that the half-lives of rimsulfuron and haloxyfop-P-methyl in fresh tobacco leaf samples were ranged from 2.4 to 3.7 days. The final residues of rimsulfuron, haloxyfop-P-methyl, and haloxyfop in flue-cured tobacco leaf samples were all lower than the LOQ. Conclusions : The results demonstrate that the developed method could be used to detect rimsulfuron, haloxyfop-P-methyl, and haloxyfop in tobacco leaf matrixes. Highlights : A method for simultaneous determination of rimsulfuron, haloxyfop-P-methyl, and haloxyfop in tobacco leaf samples with high sensitivity has been established for the first time.