Application of atmospheric pressure ionization techniques and tandem mass spectrometry for the characterization of petroleum components

•We observed nitrogen fixation for non-polar molecules (e.g. paraffins) in Atmospheric Solid Analysis Probe (ASAP) and Atmospheric Pressure Gas Chromatography (APGC).•The mechanism is likely similar to the field-assisted nitrogen fixation: C-C activation and nitrogen fixation to form an iminium ion.•The on-line fractionation effect in ASAP can help us to obtain a more complete composition for the petroleum saturate fraction.•APGC tandem mass spectrometry can be used as an alternative of the current GC-EI MRM method providing similar petroleum biomarker information.