The Bioelectronic Interface: Sensors and Switches

Posted on Wednesday, February 13th, 2008 in Event, Polymer seminars| Share this article

Chemistry Dept. Lecture Theatre 1

Seminar by Dr Jason Davis from the Inorganic Chemistry Laboratory at the University of Oxford.

The generation of functionally-active biomolecular monolayers is important in both analytical science and biophysical analyses. Our ability to monitor the redox-active state of immobilised proteins or enzymes at a molecular level, from which stochastic and surface-induced variations would be apparent, is impeded by comparatively slow electron transfer kinetics and associated signal:noise difficulties.  We demonstrate herein that, by covalently tethering an appropriate dye to the copper protein azurin, a highly oxidation-state sensitive FRET process can be established which enables redox switching to be optically monitored at protein levels down to the zeptomolar limit.  The surface-potential induced cycling of emission enables the redox potential of clusters of a few hundred molecules to be determined.

The interfacing of biomolecule with electrode is also analysed at the single molecule level by combinations of conductive probe AFM and electrochemical STM where conductance switches across an order of magnitude can be measured.  Finally, progress towards the femtomolar detection of protein binding events at suitably engineered surfaces will be discussed