RESUMO
A simple, rapid sensitive and accurate ultra performance liquid chromatography tandem mass spectrometric ( UPLC-MS/MS ) method was developed for the simultaneous determination of 2 , 4 , 6-trinitrophenol, trinitroresorcinate, trinitrophloroglucinol residues in soil. The sample was pretreated by using the modified QuEChERS ( quick, easy, cheap, effective, rigged, and safe ) method that completed the extraction and clean-up steps in one procedure. In this none buffer QuEChERS method, samples were extracted with 1% formic acid ﹢ acetonitrile, cleaned up with primary graphitized carbon black ( GCB) and C18 sorbent, then centrifuged and filtrated before detection. The pretreatment method was simple, rapid and effective and can meet the detection requirements. The UPLC-MS/MS method was performed on Waters Accucore PFP (150 mm× 2. 1 mm, 2. 6 μm) and the column temperature was 30 ℃, the gradient elution with acetonitrile and ammonium acetate as the mobile phase and the flow rate was 0. 3 mL/min. The negative electrospray ionization ( ESI-) source under the multiple reaction monitoring ( MRM ) mode and external standard method were used for quantification. The results showed that the correlation coefficients up to 0. 9942 were obtained across a concentration range of 0. 005-5. 0 mg/L. The limits of detection ( LOD) ranged from 0 . 002 to 0 . 005 mg/kg ( S/N=3 ) . The method was validated with soil samples spiked at three fortification levels (0. 01, 0. 1 and 1 mg/kg) and recoveries were in the range of 79. 3%-94. 8% with relative standard deviations (RSD) of 3. 1%-6. 6%.