Reagentless electrochemical immunoassay using electrocatalytic nanoparticle-modified antibodies

Abstract

We describe a new approach for reagentless electrochemical immunoassay sensing in which Au/Pd NPs can be "loaded" onto antibodies to create an electrocatalytic antibody that is sensitive to the oxygen reduction reaction.

Electrically Addressable Cell Immobilization Using Phenylboronic Acid Diazonium Salts

“…[8b, 13] Diazonium-modified electrodes have been used to immobilize many biomolecules including DNA, [14] proteins, [15] and peptides. [16] We have used the direct immobilization of diazonium-modified proteins to detect H 2 O 2 [17] and cytokines, [18] as well as to construct sensing platforms for multianalyte immunosensors [19] and to enable the simultaneous electrochemical detection of DNA and protein on the same electrode array. [20] The method for the functionalization of an electrode surface with phenylboronic acid pinacol ester diazonium salt is presented in Scheme 1.…”

Multifunctional Electrode Arrays: Towards a Universal Detection Platform

“…The Willner group recently introduced the use of nucleic acid-functionalized Pt-NPs as catalytic labels to detect biomolecules using the electrocatalyzed reduction of H 2 O 2 [23]. We examined the catalytic properties of palladium nanoparticles to make an electrocatalytic nanoparticle-modified antibody that is sensitive to the oxygen reduction reaction (ORR) [24].…”

Functional Nanoparticles as Catalysts and Sensors

“…Brozik and coworkers have developed a reagentless electrochemical immunoassay by using electrocatalytic NP modified antibodies that are sensitive to the oxygen reduction reaction. 74 Gold/palladium core-shell particles were appended to antitumor necrosis factor (TNF-a) antibody. The resultant "sandwich" immunoassay demonstrated catalytic activity from the tagged TNF-a antibody with a peak potential at À160 mV and a slightly smaller peak potential at À570 mV.…”