Detection of damage to DNA and antioxidative activity of yeast polysaccharides at the DNA-modified screen-printed electrode

• Published in: Talanta (Oxford) 2002-04, Vol.56 (5), p.939-947
• Main Authors: Bučková, Miriam, Labuda, Ján, Šandula, Jozef, Križková, Lı́via, Štěpánek, Ivan, Ďuračková, Zdena
• Format: Article
• Language: English
• Subjects: Antioxidants; Chemical nucleases; Damage to DNA; DNA biosensor; Screen-printed electrode; Yeast polysaccharides
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/S0039-9140(01)00654-3

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 α-tocopherol) and determined by photochemiluminescent method.