Organic Liquids Analysis Techniques
Organic liquids are weighed into smooth-walled tin capsules. These capsules can be cold-weld sealed using a special instrument. Calibrated internal standards are prepared with every batch of samples for normalization of the data. In general, 300µg of C are required for analysis, although 100ug can also be easily done. Elemental analysis must be performed first if the quantities of carbon and/or nitrogen in a sample are unknown.
The isotopic composition of organic carbon is determined by the analysis of CO2 produced by combustion on an Elementar Isotope Cube Elemental Analyser followed by "trap and purge" separation and on-line analysis by continuous-flow with a DeltaPlus Advantage isotope ratio mass spectrometer coupled with a ConFlo III.
The routine precision of the analyses is 0.20‰.