A Continuous-Flow Gas Chromatography C-14 Accelerator Mass Spectrometry System

TitleA Continuous-Flow Gas Chromatography C-14 Accelerator Mass Spectrometry System
Publication TypeJournal Article
Year of Publication2010
AuthorsMcIntyre, CP, Galutschek, E, Roberts, ML, von Reden, KF, McNichol, AP, Jenkins, WJ
Date Published2010
ISBN Number0033-8222
Keywordsams system, gc-ams, negative-ion source, RADIOCARBON ANALYSIS

Gas-accepting ion sources for radiocarbon accelerator mass spectrometry (AMS) have permitted the direct analysis of CO2 gas, eliminating the need to graphitize samples. As a result, a variety of analytical instruments can be interfaced to an AMS system, processing time is decreased, and smaller samples can be analyzed (albeit with lower precision). We have coupled a gas chromatograph to a compact C-14 AMS system fitted with a microwave ion source for real-time compound-specific C-14 analysis. As an initial test of the system, we have analyzed a sample of fatty acid methyl esters and biodiesel. Peak shape and memory was better then existing systems fitted with a hybrid ion source while precision was comparable. C-14/C-12 ratios of individual components at natural abundance levels were consistent with those determined by conventional methods. Continuing refinements to the ion source are expected to improve the performance and scope of the instrument.