UC Santa CruzStable Isotope Laboratory
SIL Home Analyses Research People Publications Photos
A-Z Index | Find People A-Z Index Find People

SIL Home

University of California
Stable Isotope Laboratory
Earth and Planetary Sciences
1156 High Street Santa Cruz, CA 95064

Lab: (831) 459-5751
Office: (831) 459-5857
Fax: (831) 459-3074

Visiting the Lab

Isotopic Analyses

Instrument Scheduling

Instrument Use Forms

Instruments Live!

Kiel Live Data
Dick Tracy Live Data
Columbo Live Data

SIL Standards Table

CIAAW website


Merck Chem. Index

Periodic Table


EOP STEM Transfer Weekend 2018

UCSC-SIL Undergraduate Reseach Grants


UCSC SIL History

EH&S Lab Safety

Lab Safety Manual
Lab Safety Training Classes
EH&S Waste Tags
SIL Chemical Inventory
Safety Data Sheets
Safety Training Checklist

Shipping Frozen Samples w/o Using Dry Ice


I am having some cetacean skin samples sent to me from overseas for C and N analysis (for a feeding ecology study). The samples will be in transit for approximately 72 hours. I cannot use dry ice to keep the samples frozen and the folks sending them to me are unable to dry the tissue. Any thoughts on how, if at all, this might affect the C and N signatures of the tissues? And if the consensus is that this will have a dramatic affect on the numbers, any suggestions on how to preserve the tissues during transit to avoid this?

Nicole Browning, University of Central Florida


A neat way to keep things cold (ca. 0°C) for 3-4 days is to place the samples in 1.5 ml Eppendorf tubes. Then, take a wide-mouthed thermos flask (metal or plastic), place the samples within it and then almost fill with water.

Without putting the top on, place the whole thing upright into a -20C freezer for a day or so. When it is completely frozen, top up with water, and place the top on the flask.

When you are ready to ship the flask, they can wrap it in a towel or something similar to insulate it. I have brought samples from Trindad to Germany in this way, and they were still frozen 4 days after I set out (I know, because my bags got lost by the airline!).

Alternatively, air-dry the samples (over a radiator?). I sometimes make a small washing line where I dry thin sections of muscle tissue in 2-3 days. They could just stick them in alcohol or even salt?

Preservation will have a small effect, but most studies indicate it is minimal....

Dr Chris Harrod, Queen's University Belfast, UK