UV Irradiation of Thymine Molecules and Gas Chromatography – Mass Spectrometry

Cyclobutane pyrimidine dimers (CPDs) are products of a photochemical reaction caused by ultraviolet (UV) irradiation of adjacent pyrimidine molecules. Thymine dimers, the most common form of CPDs in the body, are of particular interest because they are the cause of the majority of UV-induced mutations in mammals, often resulting in the development of skin cancers. Because of the photochemical properties of the reactions of thymine dimers, and the relation of these dimers to cancer pathogenesis, the formation and analysis of thymine dimers in a laboratory setting could be a useful educational tool for pre-medicine students learning about organic and photochemistry. Previous studies have shown that thymine monomers, which are normally not volatile enough for gas chromatography, are able to undergo gas chromatography after being derivatized with isobutyl chloroformate (IBCF). In this study, using IBCF as a derivatizing agent for the analysis of UV-irradiated thymine dimers, the use of gas chromatography – mass spectrometry for analysis is attempted