Effect of residues remaining in the injection liner of a gas chromatograph on the quantification of polycyclic aromatic hydrocarbons by isotope dilution mass spectrometry using deuterium-labeled internal standards.

We have investigated the differences in response ratios of native polycyclic aromatic hydrocarbons (native PAHs)/13C-labeled PAHs (13C-PAHs) and of native PAHs/deuterium-labeled PAHs (PAHs-d) in a calibration solution containing at trace concentrations (< 1 microg mL(-1)) by gas chromatography-mass spectrometry. Only the ratios of native PAHs/PAHs-d decreased significantly (p < 0.05) accompanied with increase of residue amounts originated from immediately before injected solution. Since the analytical results using PAHs-d as internal standards were significantly lower than those using 13C-PAHs whatever solutions were injected immediately before (p < 0.05, 1.9-13.2%), 13C-PAHs gave more accurate results.