C/N Sample Prep

Biogeochemical Stable Isotope Facility

School of Ocean and Earth Science and Technology

To contact us:

Lab Phone: 808-956-5362

Fax: 808-956-5512

Lab Email: isobiogeo@soest.hawaii.edu


Sample preparation for δ13C, δ15N analysis of solid samples and filters

Samples have to be dried, finely ground (except for glass fiber filters), weighed (using a microgram balance), packaged in tin capsules, and acidified (if necessary) prior to analysis. We will prepare samples for you at an additional cost.

Important things to keep in mind while preparing samples

*If your C/N is larger than 25, separate analyses for carbon and nitrogen will most likely be necessary.  In this case, total will be $18.50 for analyses of both C and N (not including preparation, if applicable).

**We are able to grind and weigh samples for you if necessary.  We prefer that the samples come to us completely dried, but can help you arrange for this process if absolutely necessary. 

***If you are studying macroalgae or sediments that contain carbonate material, acidification will be required to measure organic carbon quantity and isotopic composition.  With some materials, it has been observed that acidification will cause a nitrogen isotopic offset.  A test trial may be run to determine if this is the case with your sample material.  If so, we may need to analyze one unacidified sample for nitrogen and one acidified sample for carbon.  If we confirm that this is the situation with your samples, where two analyses are required to measure carbon and nitrogen isotopic compositions, the cost is $18.50 (not including preparation, if applicable), as in the case of a C/N larger than 25.

If you'd like to have us analyze your samples, please fill out the Sample Request Form which you can find on our Home Page.



Price $

Prepared Samples*: C & N, only C, or only N


Prepared Filters (up to 25 mm in diameter)


Prepared Sediment samples***


Unprepared samples**










filter prep (drying, sub-sampling, folding)