Ba. Bruenner et al., SIMULTANEOUS DETERMINATION OF MULTIPLE ALDEHYDES IN BIOLOGICAL TISSUES AND FLUIDS USING GAS-CHROMATOGRAPHY STABLE-ISOTOPE DILUTION MASS-SPECTROMETRY, Analytical biochemistry, 241(2), 1996, pp. 212-219
Biological oxidative stress has been associated with various degenerat
ive disorders and disease states, and accurate and sensitive methods a
re needed to determine the extent of oxidation occurring in vivo. Pero
xidation of polyunsaturated fatty acids forms complex mixtures of alde
hydes and other breakdown products because various oxidants are involv
ed and lipid composition is not uniform. Quantitative analysis of mult
iple lipid peroxidation products yields a more complete measure of bio
logical oxidation than measurement of a single aldehyde, particularly
when aldehydes exhibit marked differences in reactivity. This report d
escribes extensions of an established gas chromatography/mass spectrom
etry method to include stable isotope dilution determination in tissue
and plasma of three aldehydic products of lipid peroxidation: hexanal
, nonanal, and 4-hydroxy-2-nonenal. Use of deuterated internal standar
ds for each analyte improved precision and accuracy compared to a sing
le internal standard for all three aldehydes, Improvements are attribu
ted to differences in extraction and derivatization efficiencies for i
ndividual analytes owing to substantial differences in reactivity. Ele
ctron ionization of oxime-tert-butyldimethylsilyl derivatives gave gre
ater specificity for detecting all three aldehydes than was possible u
sing electron-capture ionization of O-pentafluorobenzyl oxime derivati
ves. Exchange of the deuterium label of [2,3-H-2]HNE internal standard
was determined to be minimal during the analyses. (C) 1996 Academic P
ress, Inc.