A-DNA modified

If we consider Figs. 3.8 and 3.9, where the results for the oxidation of guanosine and adenosine 5 -monophosphates at a bare glassy carbon electrode and at a DNA-modified electrode are presented, several facts are worth mentioning when comparing voltammograms at both electrodes. 

Sato Y, Hosokawa K, Maeda M (2008) Detection of non-cross-linking interaction between DNA-modified gold nanoparticles and a DNA-modified flat gold surface using surface plasmon resonance imaging on a microchip. Colloids Surf Biointerfaces 62 71-76... 

L. Holm and C. Sander. 1995. Evolutionary link between glycogen phosphorylase and a DNA modifying enzyme EMBO J. 14 1287-1293. (PuhMed)... 

A chronopotentiometric method for determination of amino derivatives of PAH is based on the high affinity of DNA for such compounds. In a cell consisting of a DNA-modified CPE, a reference SSCE and a Pt wire auxiliary electrode, an aqueous solution of the PAA is submitted to an accumulation period, during which the analytes are transferred to the working electrode by an intercalation mechanism, after which the solution is changed... 

Cyt c adsorbed at a DNA-modified metal electrode showed voltage-dependent orientation resulting in non-Nernstian behavior at high electrode potentials. 

Figure 5-9. Plot of the apparent formal potential of Ru(NI at a DNA-modified electrode. The concentration of Ru(NH3) " was adjusted such that I j , remained -10-20 pmol cm or approximately 5-10% of the value at saturation.

Pinijsuwan et al. [65] loaded streptavidin-coated latex particles with biotin-coated Au-NPs so as to increase the quantity of Au-NPs. Then, they attached the latex particles to biotinylated DNA probes for coli previously hybridized to a DNA-modified SPE (Fig. 4.10). The detection step involved the immersion of the modified SPE in a HBr/Brz solution, and further differential pulse anodic stripping voltammetry (DPASV) of Au + ions. Following this methodology, a detection limit of 0.5 fM was achieved. 

FefCN] ] " by methylene blue (MB] at a DNA-modified electrode. LB+ is leucomethylene blue, the product of the electrochemical reduction, (b] Cyclic voltammetry at a gold electrode modified with DNA of 2 mM [Fe(CN]6] (curve 1], 2 p.M MB (curve 2], and 2 mM [FefCNJe] and 2 p.M MB (curve 3]. Reproduced from S. 0. Kelly, E. M. Boon, J. K. Barton, N. M. Jackson, and M. G. Hill, Single-base mismatch detection based on charge transduction through DNA, Nucleic Acids Research, 1999, 27(24], 4830-4837, by permission of Oxford University Press. 

Oliveira-Brett, A.M., Serrano, S.H.P., Macedo, T.A., Raimundo, D., Marques, M.H., LaScalea, M.A. Electrochemical determination of carboplatin in serum using a DNA-modified glassy carbon electrode. Electroanalysis 8, 992-995 (1996)... 

Recent results obtained with a DNA-modified HMDE [293] unambiguously excluded the explanation offered by Flemming (reviewed in [17]). DsDNA was attached at the HMDE at potential Ea —0.1 V (i.e. at a potential more positive than the p.z.c.) the electrode was washed and transferred to the background electrolyte not containing DNA and exposed to potentials (varying from —0.1 to —1.55 V) for 100 s prior the CV measurements [293]. 

The chemical reduction of Fe(CN)g was identified as a reaction that would be catalyzed by electrochemically reduced MB intercalated within a DNA film. This electrocatalytic process is thermodynamically favored by 0.6 eV. Indeed, in the absence of MB, no signal is obtained for the anionic probe at a DNA-modified electrode, presumably because of electrostatic repulsion. In addition, the association of MB with the DNA film produces currents corresponding to the reduction of 1.4 molecules per immobilized duplex (Figure 8). However, when both MB and Fe(CN)g " are present in solution, irreversible electrochanical signals corresponding to multiple turnovers of the intercalated catalyst are observed. Only low levels of electrocatalysis were obtained when daunomycin was used as the intercalated species this probe binds DNA with higher affinity and may have slower exchange dynamics or solvent accessibility. 

Blaskova M, Hajkova A, Vyskocil V (2015) Voltammetric determination of anthracene using a DNA-modified glassy carbon electrode. Chem Listy 109(3) 235-240... 

Kelly OS, Barton JK, Jackstm NM, Lill MG (1997) Electrochemistry of methylate blue bound to a DNA-modified electrode. Bioconjugate Chem 8 31-37... 

McShane H, Brookes R, Gilbert SC, Hill AV. Enhanced immunogenicity of CD4(+) t-cell responses and protective efficacy of a DNA-modified vaccinia virus Ankara prime-boost vaccination regimen for murine tuberculosis. Infect Immun 2001 69(2) 681-686. 

For platinum metals, most typical approaches have already been summarized a bio-assay can be mentioned stiU for the determination of platinum with a DNA-modified biosensor operated in amperometric mode and potentially applicable to environmental samples of biological origin. 

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