QuEChERS-Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry for Determination of 2,4,6-Trinitrophenol,2,4,6-trinitroresorcinate and 2,4,6-Trinitrophloroglucinol in Soil
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. 9942were obtained across a concentration range of 0. 005-5. 0 mg /L. The limits of detection( LOD) ranged from0. 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%.