Voltammetric Determination of Purine Bases Using a Carbon Electrode Modified With Hybrid Silica Film

Abstract

Hybrid silica films containing cation‐exchange polyelectrolytes were designed and used to modify a glassy carbon electrode (GCE) for voltammetric determination of purine bases. Hybrid silica‐polyelectrolyte films synthesised in the presence of adenine as structure directed component have demonstrated enhanced sorption capacity to purine base. The anodic peaks of adenine and guanine at a hybrid film‐modified GCE were observed at +1.55 and +1.1 V, respectively, in phosphate buffer solution at pH 3.5. Oxidation currents of adenine and guanine were proportional to their concentration in the range of 0.02–0.50 mM, with a detection limit of 0.015 mM. The developed method was used to determine adenine in adenosine triphosphate and purine bases in hydrolyzed solutions of DNA and demonstrated good metrological characteristics.

Polyelectrolytes Assembly: A Powerful Tool for Electrochemical Sensing Application

“…This electrode was utilized for the amperometric determination of H2O2. Silica sol, prepared by the hydrolysis of tetraethyl orthosilicate (TEOS), was modified in order to obtain a cationic (with film of the PDDA and PVS) or an anionic (with PDDA) ion-exchange material [148]. After the addition of adenine, the prepared material was placed onto a GCE or a glass substrate by spin-coating.…”

Composite Silica‐Based Films as Platforms for Electrochemical Sensors

“…Polyelectrolytes can be also added to the MIS in order to induce positive or negative charges that are likely to affect the probe binding process, as reported for the voltammetric sensing of purine bases (adenine and guanine) in hydrolysed solutions of DNA. [99] Finally, it is also possible to perform chiral electrochemical recognition using very thin MIS films on ITO electrode, as pointed out for the distinction of enantiomer pairs (respectively (R)-and (S)-N,N'-dimethylferrocenylethylamine and dand l-3,4dihydroxyphenylalanine). [110] In this work, the modified electrode was not directly applied to quantitative determinations but, taking into account the attractiveness of electrochemical chiral analysis, [111] the elaboration of chiral MIS for electrochemical sensing could be a versatile and rather simple way to achieve this goal by avoiding the need to elaborate very sophisticated multicomponent systems.…”

“…MPTMS served as molecular glue between Au surface and MIS while phenyl and amino groups helped with the probe recognition via electrostatic, hydrogen bonding and “π–π” interactions (Figure 3B). Polyelectrolytes can be also added to the MIS in order to induce positive or negative charges that are likely to affect the probe binding process, as reported for the voltammetric sensing of purine bases (adenine and guanine) in hydrolysed solutions of DNA [99] . Finally, it is also possible to perform chiral electrochemical recognition using very thin MIS films on ITO electrode, as pointed out for the distinction of enantiomer pairs (respectively (R)‐ and (S)‐N,N′‐ dimethylferrocenylethylamine and d ‐ and l ‐3,4‐dihydroxyphenylalanine) [110] .…”

Recent Advances in Hybrid Biomimetic Polymer-Based Films: from Assembly to Applications

“…Other examples of cationic PE-based conjugated platforms for DNA detection include a poly{9,9-di[3-(1-ethyl-1,1-dimethyl ammonio)propyl]-2,7-fluorenyl-alt-1,4-phenylene dibromide} (PFN)-ssDNA [107], poly{(1,4-phenylene)-2,7-[9,9-bis(6'-N,N,N-trimethylammonium)-hexyl fluorene]dibromide} [158], trimethylphosphonium-substituted polyfluorenes (PTMPHFs)-ssDNA [159], and poly[(9,9-bis(6 -N,N,N-trimethylammonium)hexyl) fluorene-alt-1,4-phenylene] bromide) (PFPBr)-AuNPs-ssDNA [160], PFBT-ssDNA [161]. On the other hand, the conjunction of PE-SiO 2 NPs and a purine base results in an enhanced electroactive sorption capacity towards purine bases present in a DNA molecule [162]. This system has been applied for electrochemical determination of adenine in adenosine triphosphate and purine bases in hydrolyzed solutions of DNA at glassy carbon electrode (GCE) surface decorated with the film.…”