Determinatiom of 8‐Hydroxy 2′‐Deoxyguanosine Using Electrodes Modified with a Dispersion of Carbon Nanotubes in Polyethylenimine

Abstract

Hydroxyl radicals easily oxidize biomolecules such as proteins and DNA. The most abundant oxidative product of DNA is 8-hydroxy 2'-deoxyguanosine (8-OHdG) and this is considered a biomarker of oxidative DNA damage. This work studies the electrochemical behavior of 8-OHdG on electrodes modified with carbon nanotubes dispersed in polyethylenimine. The technique of differential pulse anodic stripping voltammetry (DPASV) enables quantification of 8-OHdG in the presence of its major interferents, such as ascorbic acid and uric acid. We obtained linear calibration plots in the range from 5.0 10 À7 M to 3.0 10 À5 M, with detection limit (DL) of 1.0 10 À7 M and the quantification limit (QL) of 3.0 10 À7 M.

Electrochemical Sensing of Uric Acid Using Glassy Carbon Modified with Multiwall Carbon Nanotubes Dispersed in Polyethylenimine

“…However, they present the disadvantage of the interference of other electroactive compounds like ascorbic acid (AA), which is oxidized at potentials similar to UA 8–19. Several strategies have been proposed to overcome this problem 8, 20 involving the modification of electrodes with polymeric membranes 10, 15, 21–25, nanoparticles 19, 26–31, cyclodextrines 19, 20, 32 and carbon nanostructures 9, 10, 12–19, 25, 28, 31, 33–38. Rodríguez et al.…”

Effects of pH on electrocatalytic activity of carbon nanotubes in polyethylenimine composites

“…Glassy carbon electrode (GCE) modified with CNT-PEI dispersion in 50/50 v/v ethanol/water solution was found to be capable of detecting 8-hydroxy 2 0 -deoxyguanosine (8-OHdG), the most abundant oxidative product of DNA. The GCE/CNT-PEI electrode was selectively and sensitively able to analyze 8-OHdG in the presence of its main interferents such as ascorbic acid and uric acid [9]. The same modified GCE was also able to sensitively, selectively, and quantitatively detect quercetin in the presence of rutin [10].…”

Electrochemiluminescence immunosensor for highly sensitive detection of 8-hydroxy-2′-deoxyguanosine based on carbon quantum dot coated Au/SiO2 core–shell nanoparticles

“…For example, electrochemical method based on poly(3-methylthiophene) (P3MT) and polyethylenimine dispersed carbon nanotubes modified glassy carbon electrode (GCE) used as working electrode allowed the sensitive determination of 8-OHdG. But the results of electrochemistry methods above were likely to be affected by other biomolecules or matrix effects [15,16]. Fluorescent sensor is the another method for 8-OHdG detection which developed in recent years.…”