Extraction of Lactic Acid from Human Plasma for Robust Stable Carbon Isotopic Analyses

摘要

An optimized extraction procedure was developed that does not result in carbon stable isotope fractionation with a standard deviation of Δδ~(13)C = ± 0.11‰ between replicate aliquots of lactic acid extracted from human plasma and derivitized to methyl lactate. The technique is reproducible and could be applied to compound specific and position specific carbon isotopic analysis of lactic acid. In the future, the extracted lactic acid can be analyzed for position specific isotope composition using a system built and described previously (Tobias et. al., 2014). This technique may also be adaptable to other small acids of interest in human plasma.