With the support of the Organic Dynamics Program, Professor Thomas L. Netzel, of the Department of Chemistry at Georgia State University, and Professor Bruce E. Eaton, of the Department of Chemistry at Washington State University, explore photoinduced electron transfer mechanisms in covalently labeled DNA oligomers. Through the synthesis and study of short, covalently modified DNA oligonucleotides, Professors Netzel and Eaton explore the rates of electron transfer among various DNA bases and representative organic electron donor and acceptor molecules, probing such issues as the rate at which an initially formed hole or excess electron within DNA will travel to its final trapping site and the nature of such trapping sites. These studies provide the information needed to design and interpret electron transfer in covalently modified DNA duplexes, wherein the skewed pi-stacking of bases suggests the possibility of enhanced electronic coupling between donors and acceptors embedded within or attached to such a pi stack. The uses of charge-separating supramolecules spans fields as diverse as artificial photosynthesis, photocopying, and optical information storage and processing, leading to great interest in developing spatially well-defined molecular assemblies designed to effect efficient charge separation through the harnessing of the energy of light. Professor Thomas L. Netzel, of the Department of Chemistry at Georgia State University, and Professor Bruce E. Eaton, of the Department of Chemistry at Washington State University, with the support of the Organic Dynamics Program, prepare and study short pieces of DNA bearing chemically attached molecules designed to probe the fundamental aspects of the charge separation process. These studies provide an initial framework for the systematic design of DNA molecules which geometrically position molecules at desired positions relative to one another for controlled light-induced charge separation.
