1. Contact the mass spec lab manager, Christine France (francec@si.edu, 301-238-1261), to discuss your project and sample preparation.  Every project and sample set is unique and may require subtle variations to the guidelines listed below.  We always strive to obtain the highest quality results for our users, so we ask that you communicate directly with the manager before preparing your samples.

2.  Fill out a project submission request form (available from the lab manager) which includes a brief description of your project and your contact information.  You will also have to include copies of permissions to destructively analyze samples, and any pertinent collecting permits.

3. Discuss the appropriate weights for your samples with the lab manager.  The following are some general guidelines for the most common types of samples, but confirm the appropriate weight with the manager before proceeding.  Please note there are other types of samples that we can accommodate that are not listed here

Animal tissues for C and N (muscle, hair, feather, nails, extracted protein, etc.) = 0.5-0.7 mg

Other organic solids for C and N = 0.4-0.6 mg

Plant tissues for C only = 0.3-0.4 mg

Plant tissues for C and N = ~10.0 mg

Soils/sediments for C and N (high organic content) = 8.0-10.0 mg

Soils/sediments for C and N (low organic contect) = 10.0-15.0 mg

Sulfates and sulfides for S = 0.4-0.6 mg

Soils, sediments, animal tissue, plant tissue for S = >10 mg

Phosphates and nitrates for O = 0.4-0.6 mg

Organic solids for O = 0.3-0.5 mg

Organic solids for H = 0.3-0.5 mg

Pure carbonates for C and O = 0.3-0.5 mg

Enamel and hydroxyapatite for C and O = 3.0-4.0 mg

4.  For EA and TC/EA analyses, weigh and pack your samples; place them in a 96-well sample tray.  Obtain the sample list template (excel format) from the lab manager and record your sample names and weights (in mg to at least 3 decimal places).  We can recommend vendors for the tin cups, silver cups, and sample trays if necessary.

Samples for EA carbon, nitrogen, or sulfur isotopes and elemental abundances - Samples should be weighed into tin cups (3.5x5mm, 4x6mm, or 5x9mm) and tightly packed into a ball.  

Samples for TC/EA oxygen isotopes - Samples should be weighed into silver cups (3.5x5mm, 4x6mm, or 5x9mm) and tightly packed into a ball.

Samples for TC/EA hydrogen isotopes - Samples for hydrogen analyses must be brought to the isotope lab at least 3 days prior to analysis to allow exchangeable hydrogen to equilibrate with our local atmospheric water vapor.  All samples for hydrogen analyses must therefore be weighed and packed at the isotope lab.  Contact the lab manager to make arrangements.  Samples should be weighed into silver cups (3.5x5mm, 4x6mm, or 5x9mm) and tightly packed into a ball.

5.  For carbonate analyses, samples will have to be delivered in bulk to the mass spec lab where they will then be transferred into the appropriate exetainer vials.

6.  We can accommodate some gaseous samples for dual inlet analyses.  Please communicate with the lab manager for details.

7.  Once your samples are prepared, submit your project submission request form and your sample templates electronically to the lab manager.  Include a paper copy of the sample templates with your trays.  Cover your trays securely and coordinate with the lab manager to either drop off your samples in person or mail them to the lab.  

Please contact the lab manager before you send your samples!  Internal SI mail can be sent to MRC 534.  Securely packed samples can be mailed to the following address:

Christine France

Smithsonian Museum Conservation Institute

4210 Silver Hill Rd.

Suitland, MD  20724