Fast and precise method for Pb isotope ratio determination in complex matrices using GC-MC-ICPMS: application to crude oil, kerogen, and asphaltene samples.

A new method to determine Pb isotope ratio without ion-exchange-matrix separation is proposed. After acid digestion, Pb was ethylated to Et(4)Pb, separated from the digested solution (black shale, asphaltene, crude oil and kerogen) by extraction in isooctane, and then injected into a gas chromatograph coupled to a multicollector inductively coupled plasma mass spectrometer. Seven isotopes ((202)Hg, (203)Tl, (204)Pb, (205)Tl, (206)Pb, (207)Pb, (208)Pb) were monitored simultaneously with peak duration of 23 s.

Direct analysis of trace elements in crude oils by high-repetition-rate femtosecond laser ablation coupled to ICPMS detection.

IR-femtosecond pulses were used at high repetition rates (up to 10 kHz) to ablate viscous crude oils for the determination of trace elements by ICPMS. A special internal glass cap was fitted into the ablation cell to minimise oil splashes and remove big particles that would be otherwise spread into the cell. Laser ablation in static and dynamic conditions (i.