Voltammetric Monitoring of Protein Aggregation from Solution Using Tris-(2,2'-Bipyridine) Osmium (II) Chloride as an Electrocatalytic Mediator

Published

February 2, 2014

Author(s)

Napoleon E. Tercero, Joseph A. Kotarek

Abstract

The present work evaluates the feasibility of tracking protein aggregation voltammetrically by taking advantage of the intrinsic electroactivity of tyrosine residues. The electrocatalytic current due to the oxidation of tyrosine, mediated by tris-(2,2'-bipyridine) Osmium (II) chloride, is used as a reporter of changes in protein aggregation state. We demonstrate, by the use of square wave voltammetry, that this system is able to detect the presence of tyrosine in peptides, differentiate between peptides of equimolar tyrosine concentration and even detect tyrosine within large entities such as antibodies and insoluble amyloid fibrils. We also determine the aggregation time course of a model peptide, amyloid beta. The method offers the prospect of monitoring biopharmaceutical aggregation and has potential to establish itself as a technique that is orthogonal to existing methods of aggregation detection.

Citation

Electroanalysis

Volume

26

Issue

2

Pub Type

Journals

Keywords

protein aggregation, square wave voltammetry, biopharmaceutical, amyloid beta

Citation

Tercero, N. and Kotarek, J. (2014), Voltammetric Monitoring of Protein Aggregation from Solution Using Tris-(2,2'-Bipyridine) Osmium (II) Chloride as an Electrocatalytic Mediator, Electroanalysis (Accessed March 13, 2025)