Nucleobases as genetic material building blocks are exposed to several modifications throughout the cellular life cycle, mostly to epigenetic mechanisms like methylation, and to oxidation as the result of aerobic metabolism. The most known studied products of such modifications are 5-methylcytosine and 8-hydroxyguanine, but there is also a multitude of other oxidation products being generated. Studies of DNA methylation and oxidative damage rate can serve as early predictors of pathogenesis and carcinogenesis, as well as for assessment of high-risk individuals and for evaluation of drug effectiveness in oxidative damage prevention. Gas chromatography provides a convenient means for analyzing nucleobase composition of DNA, including modified nucleobases. Before analyis, DNA needs to be hydrolyzed and the nucleobases converted into volatile products, usually into trimethylsilyl (TMS) derivatives. However, the procedure must be carried out under strictly controlled conditions in order to obtain consistent results and to avoid unwanted reaction products. A common problem in obtaining TMS derivatives is the presence of residual water in the sample. In the present work, a sample preparation workflow for DNA nucleobases is presented, including DNA hydrolysis and silylation. The procedure proved to be consistent in terms of reproducibility of TMS-products and to be relatively insensitive against sample residual water.
B.03 Paper at an international scientific conference
COBISS.SI-ID: 5197338Cooperation was due to the needs to implement various IC-MS, LC-MS and GC-MS methods in Lek d.d.. Eight new analytical methods were developed for the determination of decomposition products, analysis of environmental samples and determination of main active substances in final products.
F.23 Development of new system-wide, normative and programme solutions, and methods
Cooperation was due to the needs to implement LC-MS technique in Melamin. Two new analytical procedures were developed for composition determination of melamine-formaldehyde resins.
F.23 Development of new system-wide, normative and programme solutions, and methods