A Biosensing Platform Based On Graphene and Supramolecular Protein Complexes

Abstract

Generic biosensing platforms with adaptable biorecognition are desirable but difficult to design; protein immobilization onto surfaces often causes major loss of function, while achieving multi-recognition usually requires a combination of heterogeneous elements. In this thesis we demonstrate a generic biosensing platform based on multi-functional, supramolecular multi-enzyme complexes immobilized directly and non-covalently on graphene electrodes. Dihydrolipoyl acyltransferase (E2) complexes can self-assemble as a layer, preserving a supramolecular structure and specific binding capability. Platform viability is shown through binding and electrochemical detection of activity of E2’s physiological partner enzyme. The cage-like E2 complexes are robust, exceptionally versatile, and can be customized for desired binding specificity and multiplicity, providing a platform that can be adapted to sense a wide range of analytes. Conventional electrode surfaces, such as glassy carbon, did not lead to a functional biosensing platform when functionalized with E2 complexes – this highlights the major role played by graphene as a solid-state interface for these systems.

Date of Award	22 Apr 2015
Original language	English
Awarding Institution	University of Bath
Sponsors	King Saud University
Supervisor	Adelina Ilie (Supervisor) & Daniel Wolverson (Supervisor)