Skip to main content Skip to navigation
Stable Isotope Core Laboratory Sample Submission

Submitting Samples

Please contact the laboratory manager at before submitting samples!  We will work with you to determine sample size required for analysis.  We can also provide advice on other steps that may be necessary for your analysis.

Select the appropriate form below for submitting samples and use a unique identifier for each sample ID. Replicate analyses are treated as an independent sample unless there was an error on our part. If you are submitting duplicate samples, you can add a suffix to make it unique (I.E. sample1-01, sample1-02, sample1.1, sample 1.2).

Please fill out one of the following Microsoft Excel files when submitting samples:

EA/TCEA pre-weighed sample form (For submitting prepackaged samples, ready for analysis)

All analyses sample submission form (For submitting other samples than EA or TC/EA or requiring additional sample processing prior to analysis.)

If encapsulating your own samples, please view our sample weighing tutorial.

Solid samples (EA, TC/EA)

Appropriate sample amounts must be determined first by the lab manager. Samples for 13C, 15N, or 34S analysis need to be in tin capsules and samples for 18O & 2H analysis need to be in silver capsules. Samples less than 7 mg can typically fit in 4×6 mm or smaller capsules, whereas 5×9 mm capsules are sufficient for samples up to 40 mg. Please use the smallest capsule possible and fold tightly into a small sphere to reduce jams in autosamplers and reactors. For samples larger than 40 mg, use 9×10 mm capsules. Most packed capsules can be submitted in a 96 well cell plate. For large samples, 48 and 32 position trays are also available. Contact us if you need any sample trays. We have a large supply of clean trays. Secure the lid with tape and label the tray before shipping. For very small samples this is even more important. Wrapping the tray with a parafilm or adding a sealing mat before attaching the lid can ensure that samples don’t migrate out of original positions during shipping. If samples arrive leaky or packaged poorly, additional fees may be applied to double wrap in fresh tin or silver.

Extremely large samples or difficult to combust samples (wood, filters, soils) are subject to a surcharge. Contact the lab manager for more details.

If you are submitting soils from a foreign country, special importation regulations exist. Please contact us for additional shipping requirements.


Carbonates can be processed for 13C using EA techniques identified above. For 13C and 18O analysis of carbonates, we digest powdered samples with H3PO4 and analyze evolved CO2 using a ThermoFinnigan Gasbench II coupled to a DeltaPlus XP Isotope Ratio Mass Spectrometer. Samples are typically supplied in powdered form, which our lab staff weighs into exetainers and subjects to carbonate treatment. Samples can also be shipped preweighed into client’s exetainers.

Gas Samples

Dual Inlet: Pure gas samples analyzed via our dual inlet system must be in flame sealed glass tubes for the tube cracker. We will also analyze low pressure gas samples in lecture bottles or similar storage devices that terminate with 1/4″ fittings.

Gas Bench II: Impure gas samples are typically analyzed/separated as CO2 and N2O. We analyze samples in 12-mL exetainers or 20mL crimpseal vials. In some cases, use of our pre-evacuated vials may be possible. Contact the lab manager for details.

Water Samples

Gas Bench II: Samples are analyzed in 12-mL vials with septa caps. If desired, the WSU laboratory can pipette water samples to vials for a minimal charge per sample. In some cases, use of our vials may be possible. Contact the lab manager for details.

Dissolved Nitrate (NO3-): Dissolved nitrate is analyzed with the denitrifier technique, which results in conversion of NO3– to N2O using Pseudomonas aureofaciens. Send filtered water samples frozen in well sealed and labeled vials. Generally 20mL of water is sufficient for multiple tests. Please provide sample nitrate concentrations when submitting samples. Inaccurate or absent concentrations may result in a duplicate analysis fee. We do not provide nitrate concentrations with results.