DNA Biosensors for Enviromental and Clinical Analysis
The molecular recognition ability of the double stranded DNA can be used for the detection of some important analytes such as drugs or potential risk chemicals. These analytes have to interact with the DNA structure. Using carbon paste electrodes, glassy carbon electrode and screen printed electrodes as the signal transducers, the guest molecules were determined by CV and DP voltammetry as well as potentiometric stripping analysis and the results were compared with those obtained by the fluorimetric measurement with a thiazole orange derivative TO-PRO-3.
The detection schemes are based on the preconcentration of an analyte in the host biocomponent and the electrochemical measurement of the analyte itself, the competing DNA redox marker tris(1,10-phenanthroline) cobalt(III) complex or the DNA quanine-residue. Simple, fast and sensitive analytical procedures were proposed. The detection limits down to nM concentrations were obtained for the derivatives of azepine, phenothiazine, acridine, catechin, quinazoline, pyrene and phenolic antioxidants.
The DNA modified electrodes were also applied to the detection of compounds which cause damage to DNA. Some antioxidants were investigated as inhibitors of the DNA cleavage process.
M. Buckova, J. Labuda, M. Vanickova and M. Fuknova
Department of Analytical Chemistry, Slovak Technical University,