ARS | Publication request: UPDATED ESTIMATES OF THE SELENOMETHIONINE CONTENTS OF NIST WHEAT REFERENCE MATERIALS BY GC-IDMS

Submitted to: Analytical and Bioanalytical Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 28, 2006
Publication Date: April 1, 2007
Citation: Wolf, W.R., Goldschmidt, R.J. 2007. Updated estimates of the selenomethionine contents of nist wheat reference materials by gc-idms. Analytical and Bioanalytical Chemistry. 38:2449-2452.

Interpretive Summary: Updated estimates of the selenomethionine (Selnet) contents of four National Intstitute of Standardard and Technologhy (NIST)wheat reference materials have been obtained using a revised gas chromatography-stable isotope dilution mass spectrometry method. The revised method makes use of digestion with methanesulfonic acid, providing a more complete accounting of endogenous Semet than was previously obtained using an overnight denaturing treatment in 0.1 M hydrochloric acid. The NIST wheat reference materials each contain about 55% of their total Se content as selenomethionine. Information about forms of Se in reference materials adds value to these materials in Se speciation studies. Estimates of selenomethionine content are also provided for some other wheat samples, including several grown under conditions of exposure to high selenium (Se) levels. These samples also contain about 55% of their total Se content as selenomethionine. These data will be used by laboratories in the public and private sectors analyzing food materials for forms of selenium.

Technical Abstract: Updated estimates of the selenomethionine contents of four NIST wheat reference materials have been obtained using a revised gas chromatography-stable isotope dilution mass spectrometry method. The revised method makes use of digestion with methanesulfonic acid, providing a more complete accounting of endogenous Semet than was previously obtained using an overnight denaturing treatment in 0.1 M HCl. The NIST wheat reference materials each contain about 55% of their total Se content as selenomethionine. Information about forms of selemium (Se) in reference materials adds value to these materials in Se speciation studies. Estimates of selenomethionine content are also provided for some other wheat samples, including several grown under conditions of exposure to high Se levels. These samples also contain about 55% of their total Se content as selenomethionine.