MilliporeSigma
  • Amplified electrochemical hydrogen peroxide reduction based on hemin/G-quadruplex DNAzyme as electrocatalyst at gold particles modified heated copper disk electrode.

Amplified electrochemical hydrogen peroxide reduction based on hemin/G-quadruplex DNAzyme as electrocatalyst at gold particles modified heated copper disk electrode.

Biosensors & bioelectronics (2015-06-05)
Shao-Hua Wu, You Tang, Liang Chen, Xian-Gui Ma, Song-Mao Tian, Jian-Jun Sun
ABSTRACT

A new gold particles modified heated copper disk electrode (Au-HCuDE) with direct current was fabricated. The hemin/G-quadruplex horseradish peroxidase-mimicking DNAzyme (HRP-DNAzyme) was self-assembled on the heated electrode and resulted in a new biosensor denoted as HRP-DNAzyme/Au-HCuDE. By controlling the temperature of the surface of the electrode, the dramatic temperature effect on the electrocatalytic reduction of H2O2 at HRP-DNAzyme/Au-HCuDE sensing platform was demonstrated. This electrocatalytic activity of HRP-DNAzyme was enhanced with electrode temperature elevated. This method was thus preliminarily used to develop an electrochemical biosensor for highly sensitive detection of H2O2. A detection limit of 1.6×10(-7) M could be obtained (S/N=3) with an electrode temperature of 50 °C, which was more than one magnitude lower than that at electrode temperature of 0 °C. This heated electrochemical biosensor shows many merits such as easy fabrication and simple heating equipment, low cost, high thermal stability, and high sensitivity and good reproducibility.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
HEPES, anhydrous, free-flowing, Redi-Dri, ≥99.5%
Sigma-Aldrich
6-Mercapto-1-hexanol, 97%
Sigma-Aldrich
1-Hexanethiol, 95%
Sigma-Aldrich
HEPES buffer solution, 1 M in H2O
Sigma-Aldrich
HEPES, BioPerformance Certified, ≥99.5% (titration), suitable for cell culture
Sigma-Aldrich
HEPES, BioXtra, suitable for mouse embryo cell culture, ≥99.5% (titration)
Sigma-Aldrich
HEPES, ≥99.5% (titration)
Sigma-Aldrich
Trizma® hydrochloride, pH 3.5-5.0 (0.5 M in H2O), BioXtra, ≥99.0% (titration)
Sigma-Aldrich
HEPES, BioXtra, pH 5.0-6.5 (1 M in H2O), ≥99.5% (titration)
Sigma-Aldrich
Hemin, BioXtra, from Porcine, ≥96.0% (HPLC)
Sigma-Aldrich
Hemin, from bovine, ≥90%
Sigma-Aldrich
6-Mercapto-1-hexanol, 99%
Sigma-Aldrich
1-Hexanethiol, 99% (GC)
SAFC
HEPES
SAFC
HEPES
Supelco
Tris(2-carboxyethyl)phosphine hydrochloride solution, 0.5 M, pH 7.0(aqueous solution; pH was adjusted with ammonium hydroxide)
Sigma-Aldrich
HEPES, BioUltra, for molecular biology, ≥99.5% (T)
Sigma-Aldrich
Tris(2-carboxyethyl)phosphine hydrochloride, BioUltra, ≥98% (NMR)
Sigma-Aldrich
Tris(2-carboxyethyl)phosphine hydrochloride, powder
Sigma-Aldrich
Tris(2-carboxyethyl)phosphine hydrochloride, BioUltra, suitable for electrophoresis, SDS-PAGE tested
Sigma-Aldrich
Trizma® hydrochloride, anhydrous, free-flowing, Redi-Dri, ≥99.0%
Sigma-Aldrich
Trizma® hydrochloride, BioPerformance Certified, suitable for cell culture, ≥99.0% (titration)
Sigma-Aldrich
Trizma® hydrochloride, reagent grade, ≥99.0% (titration), crystalline
Sigma-Aldrich
Trizma® hydrochloride, BioUltra, for molecular biology, ≥99.0% (AT)