Comprehensive two-dimensional gas chromatography with time of flight mass spectrometry applied to biomarker analysis of oils from Colombia

► GC × GC-TOFMS is able to be used to provide usual biomarker ratio to analysis of oils. ► A detailed analysis of biomarker composition of oils from Colombia was provided by GC × GC-TOFMS. ► Coelution between lupane and 18(α)-oleanane was solved by GC × GC-TOFMS.