Research – University of Copenhagen

Research

* Single molecule fluoresence spectroscopy.

Our group studies the photophysical properties of organic fluorophores at the single molecule level and we also develop new fluorophores (silver nanoclusters) for single molecule spectroscopy applications. These characterizations are important to advance the field of single molecule detection and spectroscopy and have in recent years enabled subdiffraction limited fluorescence imaging. 

An example of a confocal fluorescence image showing a number of well separated individual molecules (20 by 20 micron) together with a fluorescence intensity trajectory, emission spectrum and fluorescence decay curve that can be recorded simultaneously from a single molecule.

Green emitting photoproducts from Terrylene Diimide after red illumination.
Liao, Z.; Hooley, E.N.; Chen, L.; Stappert, S.; Müllen, K.; Vosch, T.
J. Am. Chem. Soc. 2013, 135, 19180-19185.

Single-Molecule Characterization of Near-Infrared-Emitting Silver Nanoclusters
Hooley, E.N.; Paolucci, V.; Liao, Z.; Carro  Temboury, M.R.; Vosch, T.   
Adv. Opt. Mat., 2015, 3, 1109-1115.

With collaborators from Munich and Milan, we recently measured two-dimensional excitation-emission (2D-EEM) maps of single molecules.  Check out the conference talk video on the results.

* Silver nanocluster fluorescence.

In collaboration with other research groups, we explore the potential of using DNA and peptides as a scaffold for stabilizing fluorescent silver nanoclusters. Such metal clusters exhibit photophysical properties which can find applications in the biomedical field for sensing or imaging applications.

Figure: Range of different DNA stabilized silver nanoclusters.

Probing DNA-Stabilized Fluorescent Silver Nanocluster Spectral Heterogeneity by Time-Correlated Single Photon Counting.
Carro Temboury, M.R.; Paolucci, V.; Hooley, E.N.; Latterini, L.; Vosch, T.
Analyst 2016, 141, 123–130.

Ultrafast coherence transfer in DNA-templated silver nanoclusters.
Thyrhaug, E.; Bogh, S.A.; Carro-Temboury, M.R. Madsen, C.S.; Vosch, T.; Zigmantas, D.
Nature Communications 2017, 8, 15577.

Temperature Dependent Excited State Relaxation of a Red Emitting DNA-Templated Silver Nanocluster.
Cerretani, C.; Carro-Temboury, M.R.; Krause, S.; Bogh, S.A.; Vosch, T.
Chem. Comm. 2017, 53, 12556.

* Time-gated, Raman and Lanthanide emission microscopy.

In collaboration with other research groups, we use our confocal microscope for diffraction limited spectroscopy and imaging of a variety of samples and materials.

Image taken from ref. 1

Micro-Raman spectroscopy for the detection of stacking fault density in InAs and GaAs nanowires.
Tanta, R.; Lindberg, C.; Lehmann, S.; Bolinsson, J.; Carro-Temboury, M.R.; Dick, K.A.; Vosch, T.; Jespersen, T.S.; Nygard, J.
Phys. Rev. B 2017, 96, 165433.

Spectrally Resolved Confocal Microscopy using Lanthanide Centred near-IR Emission.
Liao, Z.; Tropiano, M.; Mantulnikovs, K.; Faulkner, S.;
Vosch, T.; Sørensen, T.J.
Chem. Commun. 2015, 51, 2372-2375.

Ref 1: Time-resolved confocal microscopy using lanthanide centred near-IR emission.
Liao, Z.; Tropiano, M.; Faulkner, S.; Vosch, T.; Sørensen, T.J.
RSC Advances, 2015, 5, 70282-70286.