A sensitive method based on programmable temperature vaporization large volume injection coupled to
gas chromatogram and high-resolution mass spectrometry (PTV-GC–HRMS) has been developed for the
determination of ultra trace levels of dioxin-like polychlorinated biphenyls (DL PCBs) in small amounts
of human blood. Blood samples (1 mL) were first extracted by column extraction and then purified with
column chromatorgraphies. Final extracts (20 L) were introduced to the PTV injector under the solvent
vent mode and detected by GC–HRMS (SIM mode). PTV parameters were observed by changing one factor
at a time (practical conditions: vent flow: 50 mL min−1, vent pressure: 0 kPa and vent time: 0.1 min),
recoveries of most PCB congeners ranged from 55.1% to 108%, and method detection limits were in the
range of 0.11–1.63 pg g−1.