title: Detection of damage to DNA and antioxidative activity of yeast polysaccharides at the DNA-modified screen-printed electrode.
abstract: A simple procedure for the voltammetric detection of the DNA damage and antioxidants protecting DNA from its damage using a disposable electrochemical DNA biosensor is reported. The carbon-based screen-printed electrode (SPE) modified by a surface layer of the calf thymus double stranded (ds) DNA was used as a working electrode in combination with a silver/silver chloride reference electrode and a separate platinum auxiliary electrode. The [Co(phen)(3)](3+) ion served as the dsDNA redox marker and the [Cu(phen)(2)](2+) and [Fe(EDTA)](-) complex compounds were used as the DNA cleavage agents under the reduction by a chemical reductant (ascorbic acid). Four yeast polysaccharides with different chemical structure were investigated as the antioxidants within the concentration range of 0.05-4 mg ml(-1) in the cleavage mixture. A remarkable antioxidative activity of polysaccharides in order mannan (Candida krusei)>extracellular glucomannan (Candida utilis)>mannan (Candida albicans)>glucomannan (C. utilis) was found which is in agreement with that refered to trolox (a structural derivative of alpha-tocopherol) and determined by photochemiluminescent method.
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemical Technology, Slovak University of Technology, Radlinskeho 9, 81237 Bratislava, Slovak Republic.
authors.forename: Miriam
authors.initials: M
authors.lastname: Bucková
authors.forename: Ján
authors.initials: J
authors.lastname: Labuda
authors.forename: Jozef
authors.initials: J
authors.lastname: Sandula
authors.forename: Lívia
authors.initials: L
authors.lastname: Krizková
authors.forename: Ivan
authors.initials: I
authors.lastname: Stepánek
authors.forename: Zdena
authors.initials: Z
authors.lastname: Duracková