We have been asked to analyze natural abundance materials with high (8-15%)
organic N.   We could standardize say bovine serum albumin with our usual
peach leaf standard, but to get the best numbers I assume that isotope
standards with a similar amount of organic N would be ideal.  Does anyone
know of a supplier of isotope standard materials with high organic N?
Alternatively, does anyone have a suggestion as to how we may standardize
these materials so that we get a good absolute isotope ratio as opposed to a
relative one?

Thanks in advance.

John

John Cliff

Dept. of Crop and Soil Sciences
3017 Ag & Life Sci. Bldg.
Oregon State University
Corvallis OR, 97331

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