title: Voltammetric microanalysis of DNA adducts with osmium tetroxide,2,2'-bipyridine using a pyrolytic graphite electrode.
abstract: DNA and synthetic polynucleotides modified with a complex of osmium tetroxide with 2,2'-bipyridine (Os,bipy) produce specific voltammetric signals at pyrolytic graphite electrodes. Based on a sufficient potential separation between the peaks of Os,bipy-modified DNA (DNA-Os,bipy) and of free Os,bipy, and using an adsorptive transfer stripping voltammetric procedure involving extraction of free Os,bipy from the electrode by chloroform, DNA-Os,bipy can be determined in an excess of the free reagent. Under certain conditions, 140 pg of DNA-Os,bipy can be detected after a 5 min accumulation period. This analysis displays a more favorable sensitivity and a better selectivity for DNA structure than oxidation of DNA guanine moieties, and offers detection of osmium DNA markers at carbon electrodes.
authors.affiliation: Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, CZ-612 65 Brno, Czech Republic.
authors.forename: Miroslav
authors.initials: M
authors.lastname: Fojta
authors.forename: Ludek
authors.initials: L
authors.lastname: Havran
authors.forename: René
authors.initials: R
authors.lastname: Kizek
authors.forename: Sabina
authors.initials: S
authors.lastname: Billová