Forensic analysis isotope ratio measurements

While the dual inlet technique is generally the most precise method for stable isotope ratio measurements, the continuous-flow technique offers online sample preparation, smaller sample size requirements, faster and simpler analyses, increased cost-effectiveness, and the possibility of interfacing with other preparation techniques, including elemental analysis, gas chromatography (GC), and liquid chromatography (LC). For these reasons, CF-IRMS is the subject of the majority of research currently being conducted in the field of forensic science [1],... 

ICP-MS has also been used to measure trace elements in archaeological native silver artifacts [345] in order to identify their geographical origins. The low detection limits provided by ICP-MS allowed analysis of trace elements on 3 to 15 mg of sample. The passivation of alloy steels using acid solutions has been studied by XPS measurements of the solid in combination of ICP-MS analysis of the passivation solutions [346,347]. When bullets are crushed on impact, striations cannot be used for identification. The percentage of antimony, trace element composition, and lead isotope ratios in bullets was measured for forensic evidence [348]. The lead isotope ratios were found to be the most useful evidence. 

The development of GC coupled via a combustion furnace to an IRMS (GC-C-IRMS) has allowed the analysis of individual compounds occurring at trace levels in very complex mixtures. Sometimes referred to as compound specific isotope analysis or isotope ratio monitoring MS (GC-irmMS), this technique has opened new fields of research in areas such as organic geochemistry, food science, medicine, nutrition, sport, forensic science, archaeology, soil science, and extraterrestrial science. The chromatographic separation in connection with the combustion of the analyte, however, exerts the strongest influence on the uncertainty of the measurement. Multidimensional GC (GC/GC) has also been coupled to IRMS for the authentication of flavor components. 

Gavron A, Smith LE, Ressler JJ (2009) Nucl Instrum Methods Phys Res A 602(2) 581-587 Goldberg SA, Richter S, Schwieters H (2002) Improved environmental and forensics measurements using multiple ion counters in isotope ratio mass spectrometry, IAEA-CN-98/3/07. In International conference on advances in destructive and nondestructive analysis for environmental monitoring... 

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