Direct electrochemistry of horseradish peroxidase immobilized on DNA/electrodeposited zirconium dioxide modified, gold disk electrode

Abstract

A novel H(2)O(2) biosensor is described which is based on immobilization of horseradish peroxidase (HRP) on DNA/electrodeposited, ZrO(2)/modified, gold electrode. The DNA is attached via its 5' end to ZrO(2) and this provides a microenvironment for the immobilization of various biomolecules and promotes electron transfer between HRP and the electrode surface. Under optimized conditions, the biosensor reduced H(2)O(2) linearly between 3.5 microM and 10 mM with a detection limit of 0.8 microM at a signal-to-noise ratio of 3. In addition, the developed biosensor shows an acceptable stability and repeatability. Importantly, the analytical methodology could be further developed for the immobilization of other proteins and biocompounds.

Direct detection and quantification of microRNAs

“…It is a somewhat recent discovery that horseradish peroxidase (HRP) can be absorbed onto DNA (or RNA) through electrostatic interaction with the negatively charged sugar-phosphate backbone. [28] Hybridization of the PNA capture probe to the miRNA target spatially localizes the negative charge for HRP adsorption. This unique technique removes the need for a target labeling step and thereby increases assay sensitivity.…”

Direct electrochemistry of glucose oxidase immobilized on ZrO2nanoparticles-decorated reduced graphene oxide sheets for a glucose biosensor

“…25,26 Its excellent electrocatalytic properties make it a good candidate for an active electrode material for the electrocatalysis of various important analytes. [26][27][28][29] Electrodeposition of ZrO 2 on a self-assembled monolayer template has been used for the fabrication of a modied gold electrode that can be employed for the sensitive determination of parathion. 30 Liu et al developed an electrochemical DNA biosensor based on the incorporation of ZrO 2 in a boron doped diamond modied electrode.…”

Emerging Multimodel Zirconia Nanosystems for High‐Performance Biomedical Applications

“…Such a grafted biosensor would provide an excellent platform for the immobilization of proteins. Furthermore, Tong et al [ 302 ] derived a novel biosensor by immobilizing the HRP enzyme over DNA/ZrO 2 /modified Au electrode. Attachment of DNA via the 5′ end to ZrO 2 developed a favorable microenvironment for the biomolecules’ immobilization.…”