Analytical procedures and quality assurance criteria for the determination of major and minor deoxynucleosides in fish tissue DNA by liquid chromatography-ultraviolet spectroscopy and liquid chromatography-thermospray mass spectrometry.
Analytical procedures and quality assurance criteria have been established for enzymatic hydrolysis of fish tissue DNA to free nucleosides and their subsequent characterization by liquid chromatography-photodiode-array ultraviolet spectroscopy and liquid chromatography-thermospray mass spectrometry. Optimization of enzymatic efficiency to assure minimal loss of modified nucleosides is described. Variability in analyte capacity factors and multiwavelength response have been compared for analyte standards and hydrolysates, and results have been used to derive qualitative and quantitative quality assurance criteria. A comparison of DNA mole percent calculated using single-wavelength quantification and multiwavelength averaging quantification indicates that less variability in data may be expected using the multiwavelength technique. Finally, the composition of DNA from liver of three species of fish widely used in mutagen/carcinogen laboratory and field studies, rainbow trout (Onchorynchus mykiss), medaka (Oryzias latipes), and brown bullhead (Ictalurus nebulosus), has been determined. Identification of deoxyuridine in the DNA hydrolysates of each fish indicates that this analyte should be measured to accurately report DNA deoxynucleoside mole percent, especially when reporting data for the methylation of deoxycytidine.
Serrano
J
J
U.S. Environmental Protection Agency, Duluth, MN 55804.
Kuehl
D W
DW
Naumann
S
S
D000818:Animals; D002851:Chromatography, High Pressure Liquid; D002853:Chromatography, Liquid; D004247:DNA / Q000032:analysis*; D005399:Fishes / Q000378:metabolism*; D007059:Ictaluridae; D007202:Indicators and Reagents; D013058:Mass Spectrometry; D009705:Nucleosides / Q000032:analysis*; D009990:Oryzias; D011786:Quality Control; D012313:RNA / Q000032:analysis; D012474:Salmon; D013056:Spectrophotometry, Ultraviolet
D007202:Indicators and Reagents; D009705:Nucleosides; D012313:RNA; D004247:DNA