In this thesis we investigated the ability of two-photon multifocal microscopy for single-molecule microscopy in live cells and organisms.

Single-Molecule Microscopy (SMM) techniques constitute a group of powerful imaging tools that enable researchers to study the dynamic behavior of individual molecules.

Detecting nanoscopic objects plays an important role in nanoscience in particular, in the rapidly growing field of nanobiology. The forebear to modern super-resolution microscopy for single molecule investigation, is fluorescence microscopy.

Single-molecule spectroscopy has become a powerful method for using organic fluorescent molecules in numerous applications.

The sequence-dependence of biomolecular interactions involving nucleic acids and proteins is essential for numerous processes inside the cell. Insights into the underlying molecular mechanisms have been obtained using various biochemical and biophysical methods on two different levels — bulk and sin…

This thesis is a collection of experimental attempts to enhance photoluminescence of fluorescent molecules and quantum dots with single gold nanorods (GNRs) and relevant applications.

Promotores: Prof.dr. D. Bouwmeester, Prof.dr. A. Fiore (TU Eindhoven)

This dissertation revolves around the design and implementation of novel instrumentation and related measurement techniques, at the single molecule level, for use in biophysical research. Chapter 1 presents an introduction to the field of fluorescence-based single molecule measurements. In particular,…

In this thesis, we study different curved single crystals because of the diversity of surface structures across their curvature.

In this work, we investigate the minute circular dichroism effects of single nanoparticles.To this aim, we apply photothermal imaging with a polarization-modulated heating beam.

Promotor: T. Schmidt, Co-promotor: S. J.T. van Noort

Spectroscopic studies on fluorescent single molecules in organic condensed matter does not only provide information about the molecule itself, but also its near environment. By suppression of phonon-induced broadening of spectral lines through cooling to low temperatures, small changes in the spectral…

Quantum position verification (QPV) - the subject of this thesis - is a novel way to authenticate unknown nodes in a quantum network without the need to physically meet up.

Promotor: Prof.dr. M.A.G.J. Orrit

In human cells, a meter-long DNA is condensed inside a micrometer-sized cell nucleus. Simultaneously, the genetic code must remain accessible for its replication and transcription to functional proteins.

Curved single crystals provide variable, but well-defined surface structures.

Promotores: Prof.dr. G.W. Canters, Prof.dr. T.J. Aartsma

Promotor: Thomas Hankemeier, Co-promotores: Heiko van der Linden, Paul Vulto

Early time-resolved experiments by Frauenfelder on the ensemble of the kinetic rebinding of CO to myoglobin molecules resulted in a stretched exponential relaxa-tion due to a very large spread of the reaction rates of individual molecules.

This thesis aims to improve the detection from ultra-weak single emitter by enhancing their emission properties with plasmonic nanostructures. We exploit the wet-chemically synthesized single crystalline gold nanorods (GNRs) as our basic frameworks in the whole studies, simply because of their unique…

Gold nanorods are biocompatible nanoparticles that present an excellent two-photon signal that can be used to get high spatial resolution inside living cells. Gold nanorods are photostable and therefore can be followed inside cells for long time, with possible applications as trackers in live cells.

A single self-assembled semiconductor quantum dot in a high-finesse optical microcavity - the subject of this thesis - is an interesting quantum-mechanical system for future quantum applications. For instance, this system allows trapping of an extra electron and thus can serve as a spin quantum memory,…

Promotor: M.A.G.J. Orrit

Acute cardiovascular syndromes, including myocardial infarction or stroke, are the principal cause of death in the Western society. The main underlying pathology of cardiovascular diseases is atherosclerosis, which is caused by the accumulation of lipids and inflammatory cells in the vessel wall, in…

This thesis consists of two main parts. The first part (Chapters 2 and 3) deals with a class of Markov process called Quasi-Skipfree (QSF) processes.

The deeper understanding of an organism's pathology is important for developing treatments. Over centuries of systematic research, clinical researchers have demonstrated that the more information they acquire about the cellular properties and their organisation in the tissue, the better they can understand…

Despite being the object of intense study, embryonic development has been difficult to model due to a number of reasons. First, complex tissues can be comprised of many cell types, of which we probably only know a subset.

In this thesis, we describe the potential of cell mechanical phenotyping for immune cell characterization, diagnosis, drug testing, as well as treatment of disease.

The focus throughout this thesis will be on gathering fundamental studies of the detailed structure and composition of the electrode/electrolyte interface effect on the rate and mechanism of key electrocatalytic reactions.

Promotor: M.T.M. Koper, Co-Promotor: L.B.F. Juurlink

In most applications, electrocatalysts exhibit a large surface area to volume ratio, for example using nanoparticles.

In this thesis, the focus lies on studying glucocorticoid receptor dynamics in living cells with the aim of understanding how this transcription factor finds its DNA target sites to regulate transcription.

Viral hemorrhagic fever (VHF) is a group of acute diseases caused by highly infectious viruses including Ebola, Lassa, Dengue viruses. Its high mortality rate poses high risk to public health, however, studies on VHF have been hampered due to the non-availability of proper models and incomplete knowledge…

Het College van Bestuur van de Universiteit Leiden heeft Suzanne van der Pluijm herbenoemd als directeur bedrijfsvoering van de Faculteit Wiskunde en Natuurwetenschappen. Haar nieuwe termijn ging in op 1 juni 2026.

Ferritin is a spherical metalloprotein, capable of storing and releasing iron in a controllable way. It is composed of a protein shell of about 12 nm and within its cavity, iron is stored in a mineral form.

Promotores: G.W. Canters, T.J. Aartsma

During my PhD research, I studied the photon statistics of light emitted by a microcavity that contains a single quantum dot (QD) on resonance.

Promotor: Prof.dr. E. Eliel, Co-Promotor: M.J.A. de Dood

Healthy aging is one of the prime goals in today's society and atherosclerosis is among the greatest causes of morbidity in elderly. Cardiovascular disease patients receiving treatment are often of advanced aged and have an aged immune system, which limits translating experimental findings to the pa…

Het faculteitsbestuur heeft prof.dr. Peter Stevenhagen, vanaf 2000 hoogleraar getaltheorie in Leiden, per 15 september 2007 benoemd tot wetenschappelijk directeur van het Mathematisch Instituut. Stevenhagen, momenteel onderwijs directeur wiskunde, is de opvolger van prof.dr. Sjoerd Verduyn Lunel, die…

The adsorption of D2 and CO2 on catalyst surfaces is studied using a molecular beam in ultra-high vacuum.

Heterogeneous catalysis is essential to many industrial applications. These catalysts are often comprised of supported nanoparticles, which contain various different surface sites.

All life on earth contains DNA, which is used to store biological information. Organisms compact their DNA in order for it to fit inside their cell(s).

The research presented in this thesis makes use of small molecules (as H2 , D2 and O2 ) on well-defined single crystal surfaces (flat Pt(111), flat Cu(211) and curved Pt(111)) to elucidate the role of surface structure and degrees of freedom in the reactant in specific surface reactions.

Promotor: T. Schmidt, Co-Promotor: B.E. Snaar-Jagalska