title: Quantitative measurement of N-acetyl-L-aspartic acid in urine by gas chromatography with negative-ion chemical ionization mass spectrometry.
abstract: A highly specific and sensitive assay for N-acetyl-L-aspartic acid has been developed. The trideuterated compound was synthesized and used as an internal standard for gas chromatography with negative-ion chemical ionization mass spectrometry. Urine samples were acidified and extracted with ethyl acetate, and the compounds converted into their pentafluorobenzyl ester derivatives. Under these conditions, sub-picogram amounts of the pure derivatives could be detected. Thus, only microliter volumes of urine samples have to be processed to achieve reliable quantification of "basal" levels of N-acetyl-L-aspartic acid.
authors.affiliation: Department of Mass Spectrometry, University Children's Hospital, University of Graz, Austria.
authors.forename: H J
authors.initials: HJ
authors.lastname: Leis
authors.forename: P T
authors.initials: PT
authors.lastname: Ozand
authors.forename: A
authors.initials: A
authors.lastname: al Odaib
authors.forename: H
authors.initials: H
authors.lastname: Gleispach
mesh_terms: D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000652:urine; D002849:Chromatography, Gas; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods
chemical_list: D001224:Aspartic Acid; C000179:N-acetylaspartate