Determination of chlorpyrifos, triazophos and profenofos in vegetables by gas chromatography with solid phase extraction using multiwalled carbon nanotubes as adsorbent

A method based on multiwalled carbon nanotubes as the solid phase extraction material had been developed for the determination of chlorpyrifos, triazophos and profenofos in vegetables by gas chromatographyflame photometric detector ( GC /FPD) .The samples were extracted with ethyl acetate and purified by multiwalled carbon nanotubes column.The eluent was a mixture of acetone∶hexane ( 1∶1, v /v) .Then concentrated and dissolved by acetone before determined by GC /FPD.The results showed that these pesticides had a good linearity in the range of 0.0025~2.0mg /L and the correlations were between 0.9998 and 0.9999.The recoveries rate and limits of detection were 83.3% ~ 96.7% and 8.21 × 10- 4~ 1.37 × 10- 3mg /kg. Application of the method to the analysis of chlorpyrifos, triazophos and profenofos in several samples, we had a satisfactory result.