Imaging and force transduction in correlative scanning force and confocal fluorescence microscopy

K.R Karimullin,A.V Naumov,Thomas Basché,M.G Gladush

doi:10.1051/epjconf/201819002002

Abstract

Correlative scanning force and confocal fluorescence microscopy has been used to study individual molecules, nanoparticles and nanoparticle oligomers. By applying a compressive force via the AFM cantilever, spectral blue and red shifts in the range of several meV/GPa have been observed for single dye molecules and semiconductor quantum dots. Moreover, individual Au nanoparticle dimers linked by a chlorophyll binding protein have been imaged in both modes and plasmonic fluorescence enhancement of the chlorophyll emission of up to a factor of 15 has been found.

Highlights

Correlative microscopies are gaining increasing attention, since they allow for correlating structure or morphology of individual nano-sized objects from a potentially heterogeneous population with their electronic or photo-physical properties
In a first set of experiments we applied compressive forces via the AFM cantilever to single terrylenediimide molecules decorated with large side-groups and deposited on a mica surface
Reversible blue and red-shifts as well as irreversible shifts were observed and attributed to different conformations of the terrylene core induced by the compressive force [4]

Summary

Introduction

Correlative microscopies are gaining increasing attention, since they allow for correlating structure or morphology of individual nano-sized objects from a potentially heterogeneous population with their electronic or photo-physical properties. We have used confocal fluorescence and scanning force (AFM) microscopy of single molecules and nanoparticles for two purposes: i) To correlate structural information with photo-physical properties, and ii) To apply compressive stress and track the effects of the impact on the electronic states by fluorescence spectroscopy.

Results

Conclusion