© 1990 Oxford University Press
other |
Vinyl chloride-induced DNA adducts I: Quantitative determination of N2,3-ethenoguanine based on electrophore labeling
Chemical Industiy Institute of Toxicology, Department of Biochemical Toxicology and Pathobiology PO Box 12137, Research Triangle Park, NC 27709 USA
3To whom correspondence should be addressed
1Present address:Hüls AG, PS Biologic und Toxikologie, Postfach 1320, D-4370 Marl, FRG
2Present address: Department of Pathology, Campus Box 7095, University of North Carolina, Chapel Hill, NC 27599, USA
A sensitive assay for quantitative determination of the vinyl chloride (VC)-induced cyclic DNA adduct N2,3-ethenoguanine (EG) was developed. The method is based on the detection of EG as its di-pentafluorobenzyl derivative (3,5-PFB2-EG) This compound exhibited good gas chromatographic properties and was detected with high sensitivity by gas chromatography with electron capture detection (limit of detection 300 amol/µl injected solution) or with negative ion chemical ionization mass spectrometry monitoring the [M-181] fragment ion at m/z 354 (GC-NICI MS, limit of detection 190 amol/µl injected solution).EG, its 13C-labeled analog {13C4]-EG and 3,5-PFB2-EG were synthesized and characterized by UV and fluorescence spectrophotometry, 1H- and 13C-NMR spectroscopy and mass spectrometry. The standards were used to optimize the isolation of EG and its derivatization with pentafluorobenzyl bromide (electrophore labeling) at fmol quantities. DNA solutions were spiked with EG, the DNA was depurinated by mild acid hydrolysis, and EG was isolated from the hydrolysates by low-pressure strong cation exchange chromatography with subsequent C18 solid-phase extraction. The extracted EG was electrophore labeled and 3,5-PFB2 EG was detected using GC-NICI-MS. [13C4] EG served as internal standard. 3,5-PFB2-EG was quantitated relative to its 13C-labeied analog by measuring the ion ratio m/z 354/358. The limit of detection for the complete method was 60 fmol EG/µmol guanine. The method was applied to liver DNA from young Sprague-Dawley rats exposed to 600 p.p.m. VC from day 10 through day 14 after birth. The EG concentration in these samples was 1.8 ± 0.3 pmo/µmol guanine.
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
E. J. Morinello, H. Koc, A. Ranasinghe, and J. A. Swenberg Differential Induction of N2,3-Ethenoguanine in Rat Brain and Liver after Exposure to Vinyl Chloride Cancer Res., September 15, 2002; 62(18): 5183 - 5188. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. J. Morinello, A.-J. L. Ham, A. Ranasinghe, J. Nakamura, P. B. Upton, and J. A. Swenberg Molecular Dosimetry and Repair of N2,3-Ethenoguanine in Rats Exposed to Vinyl Chloride Cancer Res., September 15, 2002; 62(18): 5189 - 5195. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. J. Marnett Oxyradicals and DNA damage Carcinogenesis, March 1, 2000; 21(3): 361 - 370. [Abstract] [Full Text] [PDF] |
||||

