Supramolecular Immobilization of Xanthine Oxidase on Electropolymerized Matrix of Functionalized Hybrid Gold Nanoparticles/Single-Walled Carbon Nanotubes for the Preparation of Electrochemical Biosensors

Abstract

Glassy carbon electrodes modified with single-walled carbon nanotubes and a three-dimensional network of electropolymerized Au nanoparticles capped with 2-mercaptoethanesulfonic acid, p-aminothiophenol, and 1-adamantanethiol were used as hybrid electrochemical platforms for supramolecular immobilization of a synthesized artificial neoglycoenzyme of xanthine oxidase and β-cyclodextrin through host-guest interactions. The ensemble was further employed for the bioelectrochemical determination of xanthine. The biosensor showed fast amperometric response within 5 s and a linear behavior in the 50 nM to 9.5 μM xanthine concentration range with high sensitivity, 2.47 A/(M cm(2)), and very low detection limit of 40 nM. The stability of the biosensor was significantly improved and the interferences caused by ascorbic and uric acids were noticeably minimized by coating the electrode surface with a Nafion thin film.

Highly Sensitive and Selective Electrochemical Detection of Dopamine using Hybrid Bilayer Membranes

“…The linear concentration range was found to be 1 to 80 pM, leading to a correlation coefficient of 0.99 and the calibration curve of y = 6.58 × 10 À 3 x + 1.26. As a result, the lower limit of detection was calculated as 0.41 pM for DA, based on the equation LOD = 3σ/λ, [32] where the standard deviation of the blank solutions s was 0.89~0.9 % and the slope of the calibration curve was 6.58 × 10 À 3 . This resulting LOD was amazingly at least three orders of magnitude better than any previously reported value for the electrochemical detection of DA in the presence of AA interference.…”

Layered Metal Nanoparticle Structures on Electrodes for Sensing, Switchable Controlled Uptake/Release, and Photo‐electrochemical Applications

“…The binding of the horseradish peroxidase, HRP, glycoprotein to the Au NP matrix ( Figure A, Panel I) resulted in a Au NP–HRP hybrid electrode that allowed the analysis of H 2 O 2 through its electrocatalytic reduction (Figure A, Panel II). In another study, Au NPs were functionalized with ( 11 ), ( 12 ), and mercaptoadamantane, ( 14 ). The resulting NPs were electropolymerized on a single‐walled carbon nanotube (SWCNT)‐functionalized glassy carbon electrode to yield a bis aniline‐crosslinked conductive Au NP matrix.…”

“…Panel II – amperometric responses of: a) a tyrosinase‐functionalized, thioaniline‐coated, non‐nanostructured Au electrode, and b) electropolymerized cysteamine core polyamidoamine G‐4 dendron‐coated Au NP‐modified electrode, to successive additions of 100 μM catechol solution to 10 mL of 0.1 M sodium phosphate buffer, pH = 7.0, at E = 100 mV vs. Ag/AgCl. Reproduced with permission . Copyright 2012, The Royal Society of Chemistry.…”

“…[ 29 ] Copyright 1999, The Royal Society of Chemistry. In another study, [ 35 ] Au NPs were functionalized with ( 11 ), ( 12 ), and mercaptoadamantane, ( 14 ). The resulting NPs were electropolymerized on a single-walled carbon nanotube (SWCNT)-functionalized glassy carbon electrode to yield a bis aniline-crosslinked conductive Au NP matrix.…”

Mesoporous silica thin film mechanized with a DNAzyme-based molecular switch for electrochemical biosensing

“…Several electrochemical, fluorescent, colorimetric and electrochemiluminescent sensors for copper have been designed [4][5][6][7][8][9]. Among these, excellent results have been reported for fluorescent biosensors based on specific Cu(II)-specific DNAzyme [10][11][12], but electroanalytical methods based on similar DNAzymes have not been described despite the high sensitivity, low cost, flexibility and miniaturization facility of electrochemical biosensors [13][14][15][16][17].…”