Dr. Krzysztof Slowinski (Chemistry & Biochemistry)
M.S. Chemistry, Warsaw University (1992)
Ph.D. Analytical Chemistry, Warsaw University (1997)
Postdoctoral, University of California at Berkeley (1997-2000)
Bio-molecular electronics, analytical chemistry, electrochemistry
The mechanism of long-range electron transfer (ET) through DNA is currently in the center of a vigorous debate. The possibility of the efficient electronic conductivity of DNA has important biological consequences. The positive charge migration from the product of guanine (G) oxidation (guanine radical cation) to GGG sequence or other G clusters along DNA helix may be responsible for point mutations occurring far away from originally damaged guanine. Several hot-spot codons of the p53 tumor suppressor genes contain GGG sequences. Therefore, long-range electron transfer through DNA helix may play role in carcinogenesis. Electronic characterization of DNA assemblies is also important in developing the DNA sensors. For example, the single-nucleotide polymorphisms are thought to cause substantial inhibition of electron transfer along the helix. Therefore, the conductivity measurements of DNA fragments may lead to development of new devices for point mutation detection.
My Lab is interested in developing simple and robust methods allowing measurements of the conductivity of the DNA fragments. We use a well organized monolayer of DNA duplexes self-assembled on a metal electrode. The conductivity of short double-stranded DNA fragments is measured using a mercury tunnel junction device constructed in our lab. We also use electrochemical scanning tunneling microscopy to measure the electrical conductivity of single DNA molecules. The results of our research will provide information on mechanism and efficiency of electron transfer through various DNA fragments. They will also lead to a better understanding of DNA conductivity as a function of a molecule structure and will help to develop new DNA sensors.
Slowinski Group Publications:
(* denotes undergraduate co-author)
Wierzbinski, E., Arndt, J.*, Hammond, W.*, Slowinski K., In-Situ Electrochemical Distance Tunneling Spectroscopy of ds-DNA Molecules. Langmuir, 2006 in press
York, R.L.*, Nacionales, D.*, Slowinski, K., Electrical Resistivity of Monolayers and Bilayers of Alkanethiols in Tunneling Junction with Gate Electrode. Chemical Physics, 2005, 319, 235
Sek, S., Bilewicz, R., Slowinski, K., Wiring of α, ω - Alkaneditiols Into Electrical Circuit. Chemical Communications (Royal Society) 2004, (4), 404
York, R.L.*, Nguyen, P.T*., Slowinski, K., Long-Range Electron Transfer through Monolayers and Bilayers of Alkanethiols in Electrochemically Controlled Hg-Hg Tunneling Junctions, Journal of the American Chemical Society 2003, 125, 5948
York R.L.*, Slowinski K., Electron Tunneling through Single- and Two Component Bilayers in Hg-Hg Tunneling Junctions
Journal of Electroanalytical Chemistry 2003, 550-551, 327
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