Stable Isotope Facility

University of Wyoming

Solid Samples for δ 13C / δ 15N /δ 34S / δ 18O / δ 2H analysis

  • Samples should be thoroughly dried, ground and well mixed. Samples pretreated with acids need to be given at least 5-8 rinses with distilled water to get rid of all the acid in the sample.   
  • If you have enriched samples or decide to load your natural abundance samples yourselves please use 96 well plastic trays. Samples should be loaded according to the tray loading template. Please leave the well number marked for lab standards empty.
  • Group samples of similar material together, e.g., keratin with keratin and plants with plants.  If different types of samples e.g., keratin, chitin, plant, are all in the same tray label what type of sample they are in the loading template. 
  • A soil permit must accompany any soils mailed to SIF.  If submitting soil samples please contact SIF before sending for permit and instructions.  
  • If sending samples for us to weigh; fill out only the sample Id column in the tray loading template.  Samples can be sent in eppendorf tubes, glass/plastic vials, envelopes.  They should be dried and ground(unless we are performing the grinding).  Clearly label the container with the label used on the tray loading template.
  • Regardless of whether we weigh samples or sent to the lab already weighed, the sample IDs should be unique. Do not repeat sample ID names.  The names should be less than 20 characters long and cannot include special characters  (e.g. ! @ # $ % ^ & * ( ) . / \ +.";') on the sample list. Only hyphens ( - ) are acceptable.
  • Secure the trays with two pieces of tape on opposite sides of the tray and label the tray according to the tray template.  Do not use parafilm or completely wrap the tray in tape.  If sending in the mail it is advised to cut a piece of card stock or thin cardboard and place in between the tray and the lid to prevent samples from moving from well to well during shipment.  Turn the tray over and gently shake to make sure no sample leaks from capsules and samples do not move from well to well.
  • Pack shipment box well enough to prevent any breakage of vials or loss of sample.  Envelopes are not suggested because damage can occur during shipment and samples can be lost.  UWSIF is not responsible for sample loss due to shipping and packaging.
  • If submitting samples for solid hydrogen analysis please contact SIF before sending.  Hydrogen analysis can be complicated because hydrogen readily exchanges with atmospheric hydrogen.  Special procedures must be followed in order to get accurate results.  Special preparation charges may apply.

Loading sample guidelines

  • Load samples in the proper size and type of capsules. You can order the 3.5x5 mm, 4x6 mm, and 5x9 mm capsules from Costech.
  • Use the smallest capsule size that will hold the sample with no leakage
  • Use tin capsules for δ13C / δ15N analysis
  • Use silver capsules for δ18O / δ2H analysis
  • Make sure the capsule does not have any protrusions and is 

Keep the working area, weighing table and spatula and forceps very clean. Wipe the forceps and spatulas with Kimwipe in-between subsequent samples. Capsules should be folded and crushed into a cube or ball without any protrusions.  Samples that are flat or have protrusions tend to get stuck in the sample carousel. Record the final weight after the capsule is sealed. For elemental C and N analysis, the same sample loading procedure should be followed.  Also, please ensure that no sample is leaking from the tin.


Required sample size:

δ 13C / δ 15N /δ 34S                                δ 13C only  

Sample Size CNS                                                                Sample Size C Only

Sample Type         Weight in mg (milligrams)                         Sample Type         Weight in mg (milligrams)

Blood                      0.5-0.62                                               Blood                    0.2-0.3                                        

Keratin                    0.75-0.85                                             Keratin                  0.2-0.3

Collagen/bone         0.75-0.85                                             Collagen/bone        0.2-0.3

Chitin (insects)        0.75-0.85                                             Chitin (insects)       0.2-0.3

Muscle/Tissue          0.75-0.85                                             Muscle/Tissue        0.2-0.3

Plants                     2-2.5                                                    Plants                   0.2-0.3

Roots                     4-4.5mg                                                Roots                    0.2-0.3

Soils                      Contact SIF                                            Cellulose               0.2-0.3

Other                    Contact SIF                                             Soils                       10


δ 18 O / δ 2


Sample Size O&H
Sample Type Weight in mg (milligrams)
Blood 0.2-0.3
Keratin 0.2-0.3
Collagen/bone 0.2-0.3
Chitin (insects) 0.2-0.3
Muscle/Tissue 0.2-0.3
Plants 0.2-0.3
Roots 0.2-0.3
Cellulose 0.2-0.3
Phosphates 0.2-0.3


Or please refer to our Excel sample calculator for CN analysis.

Sample Loading Templates

Click on blue template link below to download.
Sample Sheet templates table

Job Code




EA-IRMS organic, δ13

Natural Abundance

100 Carousel 

 Sample diameter


Natural Abundance 

50 Carousel

 Sample diameter


Isotopically Enriched

100 Carousel

 Sample diameter


Isotopically Enriched

  50 Carousel

Sample diameter



EA-IRMS organic, δ15N


EA-IRMS organic, δ13C+δ15N


EA-IRMS organic, δ13C+C%+N%


EA-IRMS organic, δ15N+C%+N%


EA-IRMS organic,  δ13C+δ15N+C%+N%


EA-IRMS organic,  δ13C+δ15N+δ34SC%+N%+S%

100 Carousel CNS

50 Carousel CNS



Elemental Composition, %C+%N

100 Carousel

50 Carousel

32 Carousel


TC/EA-IRMS, solids, δ18O

TC/EA Organic

TC/EA Phosphate


TC/EA-IRMS, solids, δ2H


TC/EA-IRMS, solids, δ2H+δ18O



I have reviewed the sample submission procedures and downloaded and filled out the correct template.  Please take me to the order form.

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