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dc.contributor.advisorKohler, Bern
dc.creatorCoons, Marc
dc.description.abstractDNA undergoes photochemical reactions when exposed to ultraviolet (UV) radiation. The photochemical products cause mutations which can lead to cancer and apoptosis. Upon exposure to UV radiation, the major photochemical products are cyclobutane pyrimidine dimer (CPD) and the pyrimidine-(6-4)-pyrimidone photoadduct. After photoexcitation, relaxation from the excited 1ππ* state results in a [2 + 2] cycloaddition between adjacent thymine bases forming CPDs. Due to the ultrafast timescale of dimerization, it has been proposed that thymine bases must have the proper geometry before excitation. It is the purpose of this study to obtain experimental evidence for this theory: the ground state control theory. To prepare a system of thymine bases, a room temperature trehalose/sucrose glass was used to encapsulate free thymine bases, thymidine monophosphate (TMP), and thymidylyl-(3’-5’)-thymidine (dTpdT) in a pH 7 buffer solution. The glass samples were irradiated with 254 nm UV light from a mercury lamp. A UV-Vis absorption spectrum was recorded for each sample at varying time intervals of irradiation until there was no further decrease in absorbance at 260 nm, indicating that the photochemical reaction is at equilibrium. The quantum yields in the sugar glass increased at least 10-fold for thymine and TMP and over 40-fold for dTpdT relative to the quantum yields in buffered solution.en
dc.description.sponsorshipNational Science Foundationen
dc.description.sponsorshipCollege of Arts and Sciencesen
dc.publisherThe Ohio State Universityen
dc.relation.ispartofseriesThe Ohio State University. Department of Chemistry Honors Theses; 2009en
dc.subjectBase Stackingen
dc.subjectQuantum Yielden
dc.titleKinetics of UV Photodegradation of DNA Model Systems in a Room Temperature Sugar Glassen
dc.description.embargoNo embargoen
dc.rights.ccAttribution 3.0 Unporteden_US

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Attribution 3.0 Unported
Except where otherwise noted, this item's license is described as Attribution 3.0 Unported