Determination of Residues of 14 Insecticides in Honey by UPLC-MS/MS

UPLC-MS/MS was applied to the simultaneous determination of residues of 14 insecticides in honey, with the applicability screening for homemade chlorpyrifos-D₁₀ as the isotope internal standard. The sample was extracted with acetonitrile, and the extract was cleaned up with amino purification column. The purified solution was separated on an ACQUITY UPLC BEH C₁₈ chromatographic column with a mixture of methanol and ammonium formate solution (2 mmol·L^-1) as the mobile phase for gradient elution. Electrospray ionization in positive mode and the multi-reaction monitoring mode were adopted in MS analysis. Chlorpyrifos, propargite, hexythiazox, coumaphos, fenthion, phosalone, chlorpyrifos-methyl and pirimiphos-methyl were proved to be suitable for internal standard quantification; while tebufenpyrad, pyridaben, spirodiclofen, etoxazole, fenpyroximate and fenitrothion were quantitified with matrix matching method. The same linearity range of 14 insecticides was 1.0-200 μg·L^-1, with detection limits (3S/N) of 0.01-0.20 μg·kg^-1 and the lower limits of determination (10S/N) of 0.03-0.50 μg·kg^-1. Recovery rates obtained by standard additon mehtod ranged from 81.9% to 129% and RSDs (n=6) were within 11%.