Past colloquia and seminars


Resolving the Spectrum of a Plasmon Enhanced Fluorescent Dye

Academic or specialist Thesis defense

The study of fluorescent molecules (fluorophores) as light emitters has been for a long time a major field of research. Fluorescent molecules are used as dyes and markers in a multitude of interdisciplinary imaging techniques, where there can be used for instance as markers in fluorescent microscopy to image objects that are below the diffraction limit of the used light source. Fluorophores exhibit alot properties that can be taken advantage of when realising application, for instance the stoke shift or the F¨oster energy transfer (FRET). Deeper understanding of these properties allows to further improve existing applications and may even lead to new applications.
In this work, the spectral reshaping of a ATTO542 fluorescent dye (fluorophore) in the vicinity of a 40x68nm gold Nanorod (AuNR) was studied. The structures were prepared in a T-shaped scaffold using the DNA-Origami Method. This method allows the positioning of the fluorophore and the AuNR with nm precision in relation to each other, as well as the immobilization of the whole structure on a glass slide, to study under a microscope. The structures were studied under a confocal fluorescence microscope that allowed imaging single-molecules and localizing them. Once localized, the light of the structures were guided into a spectrograph, to see the emission spectrum.
The findings of this thesis supports the current research on the field. We can show that spectral reshaping of a fluorescent molecule with a gold nano particle is possible and can be described using the formalism put forward by other research.

When? 05.05.2023 16:00
Where? PER 08 0.51
Chemin du Musée 3
1700 Fribourg
speaker Bruder Nicolas, présentation du travail de Master de Physique
Contact Département de physique