Electrochemical Study and Direct Determination of Adenosine‐5′‐Monophosphate Coupled to 6‐Thioguanosine and a Glassy Carbon Modified Electrode with Gold Nanoparticles

Abstract

The direct accumulation of 6-thioguanosine (6-TG) and its electrochemistry has been studied by cyclic voltammetry in different conditions physical and chemical. In a first moment the surface of electrode was modified with gold nanoparticles. This modification was realized by electrodeposition on the active surface of a glassy carbon electrode with a HAuCl 4 solution. The nucleotide 6-thioguanosine was deposited in this gold nanoparticles monolayer. The study of accumulation of other nucleotide, adenosine 5'-monophosphate (AMP), was realized by the direct reaction with 6-TG deposited. The conditions of the reaction and its electrochemical response were tested to fix the ideal conditions of its determination. The ideal conditions of formation of the monolayer and its electrochemical response were studied; the possibility of preconcentration of 6-TG nucleotide in gold nanoparticles, the possibility of catalysis and limits of identification and quantification were also determined. The method proposed can be applied in direct determination of oligonucleotides. In this respect we applied it in the determination of AMP in a commercial product of infantile nutrition.

Gold Nanoparticles in Chemical and Biological Sensing

“…AuNPs have been used for enhanced electrochemical detection of numerous small molecules − including glucose, − dopamine, − uric acid, − ascorbic acid, − ,− epinephrine, ,− bisphenol A, nitrite, − etc. Identification of several phenolic compounds; e.g.…”

Electrochemical fabrication of metallic nanostructured electrodes for electroanalytical applications

“…Many researchers have chosen to electrodeposit metals onto untreated substrates in order to maintain an overall clean surface, thereby avoiding possible complications in later applications with surface capping organic moieties. In particular, recent research in the sensor field has focussed on the electrodeposition of several of the noble metals as a sensing layer, in particular gold, [13][14][15][16][17][18][19] silver [20][21][22][23][24] and platinum. [25][26][27][28] An example of hierarchical nanostructured gold is shown in Fig.…”

Biochemical Characterization of Human Guanylate Kinase and Mitochondrial Thymidine Kinase: Essential Enzymes for the Metabolic Activation of Nucleoside Analog Prodrugs

“…GMP was detected in the concentration range from 50 µM to 1200 µM, and saturation started above this value. Mora et al [130] developed an analytical method for the determination of AMP (adenosine 5´-monophosphate) coupled to 6-thioguanosine and a glassy carbon electrode with gold nanoparticles. In comparison, our approach is different because it is an enzyme-based detection of nucleotides which could be applied to any type of kinases in general, and can be used for studying their kinetics.…”