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Updated: Dec 29, 2025

Cellular Lipid Extraction for Targeted Stable Isotope Dilution Liquid Chromatography-Mass Spectrometry Analysis
Published on: November 17, 2011
Multi-element (C, H, Cl, Br) stable isotope fractionation as a tool to investigate transformation processes for
Ann Sullivan Ojeda1, Elizabeth Phillips, Barbara Sherwood Lollar
1Department of Geosciences, Auburn University, Auburn, Alabama 36849, USA. asojeda@auburn.edu.
Abstract:
Compound-specific isotope analysis (CSIA) is a powerful tool to evaluate transformation processes of halogenated compounds. Many halogenated hydrocarbons allow for multiple stable isotopic systems (C, H, Cl, Br) to be measured for a single compound. This has led to a large body of literature describing abiotic and biotic transformation pathways and reaction mechanisms for contaminants such as chlorinated alkenes and alkanes as well as brominated hydrocarbons. Here, the current literature is reviewed and a new compilation of Λ values for multi-isotopic systems for halogenated hydrocarbons is presented. Case studies of each compound class are discussed and thereby the current strengths of multi-element isotope analysis, continuing challenges, and gaps in our current knowledge are identified for practitioners of multi-element CSIA to address in the near future.
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