Isotopic analysis of Dissolved Inorganic Carbon in water samples.

Sample Requirements

• Water samples can be sent in any suitable container that is filled to the top (no air bubble). It is best if the sample is enclosed in a septa sealed vial.
• Please note that we need to know the approximate DIC concentration in the sample. This allows us to estimate the amount of water sample that will be processed for analysis.
• Samples should be grouped together based upon anticipated DIC content.
• Stable Isotope Facility does not accept samples that have been preserved using mercuric chloride or sodium azide.

Samples are analyzed using our Trace Gas Inlet inlet coupled to the Isoprime IRMS (Elementar).  Water samples are reacted with phosphoric acid in a sparged serum bottle and mixed for 4-6 hours.  The bottles are then allowed to equilibrate overnight before analysis on the TG-IRMS. Isotope data is calibrated by preparing in house calibrated standards the same way as the samples. The aqueous to gas phase ratio is kept constant between the sample and standard bottles.