Debye colloquium - Prof. dr. Peter Zijlstra (TU/e)

The nanotorch: plasmonic nanoparticles shine light on single molecules for biosensing

Biomolecular sensing is fundamental to our understanding of disease mechanisms, and to develop platforms toward diagnostics. Detection of single molecules remains  challenging, particularly in complex biological fluids. In this talk, I will present our recent work on the use of plasmonic nanoparticles to amplify the signal of a single molecule. I will discuss the basic principles of plasmon resonances, and how the strong electric field near a nanoparticle can be used as a nanotorch to illuminate single molecules for their enhanced detection. 

I will then describe our recent efforts to use plasmon-enhanced detection to monitor single-molecule interactions on short timescales. Herein we use plasmon-enhanced fluorescence to amplify single-molecule signals and enable the tracking of transient interactions on microsecond timescales. I will then explain the application of plasmonic biosensing toward diagnostics, enabling the continuous monitoring of concentration fluctuations by tracking single-molecule interactions directly in blood serum.