Electrochemical sensors based on stationary electrodes and immobilized DNA or its fragments and the assessment of their analytical potentials

Amperometric biosensors were developed on the basis of stationary mercury-film and glassy-carbon electrodes and DNA or its fragments, oligodeoxynucleotides (ODNs), immobilized in a nitrocellulose matrix. Taking into account the high affinity of Cu(II) and Fe(III) ions to denatured DNA ((19.1 ± 0.1) ×105 and (1.4 ± 0.3) × 105 L/mol, respectively), a procedure was proposed for the voltammetric determination of these ions in natural materials and blood serum at a level of n × 10-11 M. This procedure involves analyte pre-concentration on a DNA-containing biosensor. An ODN-containing biosensor (DNA probe) was used in the study of DNA hybridization for the highly specific determination of its nucleotide sequence. © 2005 Pleiades Publishing, Inc