TY - JOUR A1 - Solomun, Tihomir A1 - Sturm, Heinz T1 - Bringing electrons and microarray technology together T2 - The Journal of physical chemistry / B Letters N2 - Low-energy secondary electrons are the most abundant radiolysis species which are thought to be able to attach to and damage DNA via formation and decay of localized molecular resonances involving DNA components. In this study, we analyze the consequences of low-energy electron impact on the ability of DNA to hybridize (i.e., to form the duplex). Specifically, single-stranded thymine DNA oligomers tethered to a gold surface are irradiated with very low-energy electrons (E = 3 eV, which is below the 7.5 eV ionization threshold of DNA) and subsequently exposed to a dye-marked complementary strand to quantify by a fluorescence method the electron induced damage. The damage to (dT)25 oligomers is detected at quite low electron doses with only about 300 electrons per oligomer being sufficient to completely preclude its hybridization. In the microarray format, the method can be used for a rapid screening of the sequence dependence of the DNA-electron interaction. We also show for the first time that the DNA reactions at surfaces can be imaged by secondary electron (SE) emission with both high analytical and spatial sensitivity. The SE micrographs indicate that strand breaks induced by the electrons play a significant role in the reaction mechanism. PB - Soc. CY - Washington, DC KW - Low energy electrons KW - DNA hybridization KW - Low voltage SEM KW - Fluorescence PY - 2007 UR - https://opus4.kobv.de/opus4-bam/frontdoor/index/index/docId/15840 AN - OPUS4-15840 SN - 1520-6106 SN - 1089-5647 VL - 111 IS - 36 SP - 10636 EP - 10638 AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany