Intrigued by the way cells autonomously regulate their fate, we strive to understand and visualize cellular processes as the basis of Cell Signaling.

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

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.

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.

Promotor: T. Schmidt

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.

Since the early 1990s, one can isolate the optical signal of a single molecule and single-molecule spectroscopy has quickly grown into an important research field.

The Microscopy Unit houses, maintains and coordinates most of the microscopy equipment of the IBL. The available equipment ranges from conventional light and fluorescence microscopes, to confocal laser scanning and electron microscopes. In addition, infrastructure is available for histology, including…

We study cell-fate decision-making using embryonic stem cells as a model system. Stem cells integrate a large number of cues to direct their development into a great variety of cell types.

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

Optical detection of a single electron using a single molecule has never been done. Leiden physicist Michel Orrit and his team have now identified a molecule that is sensitive enough to detect an electron at a distance of hundreds of nanometers. The results are published as a cover article in ChemPh…

Promotor: M.A.G.J. Orrit

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

How can novel bioimaging technologies and vertebrate model species be used to gain a better understanding of early cellular behaviours with the ultimate goal to increase our understanding of human development and disease processes?

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.

In surface science there is great effort to move from studying simple, flat model surfaces in vacuum to investigating more complex model catalysts in gas environments (in situ). This thesis gives three examples of such studies using microscopy and spectroscopy.

Research groups in the Biological & Soft Matter Programme unravel mechanisms in biological processes and develop novel bio-inspired soft materials.

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…

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

This is a yearly event where we move in one week from the physics of light through the composition of the microscope, fluorescence microscopy and end up with some image analysis All the lectures are backed by practicals to really put your obtained knowledge into practice

Can we find new chemical and biological sensing routes on the edge and surface of graphene to improve the potential of graphene to act as a sensor?

The Royal Netherlands Academy of Arts and Sciences (KNAW) selects prominent researchers as members based on their scientific achievements. On September 17th, the KNAW will install 21 new members, including Leiden physicist Michel Orrit.

Wiskunde en Natuurwetenschappen, Leiden Academic Centre for Drug Research (LACDR)

The Royal Netherlands Academy of Arts and Sciences (KNAW) selects prominent researchers as members based on their scientific achievements. On September 17th, the KNAW will install 21 new members, including Leiden physicist Michel Orrit and chemist Hermen Overkleeft.

Electron microscopy has become an extremely important techniquein a wide variety of elds.

The aim of this facility is to accelerate biomedical research by providing access to advanced light and electron microscopy and by sharing expertise about sample preparation, imaging modalities, data storage and image analysis.

Bioactive Molecules is one of the four research themes of the Institute of Biology Leiden.

Wiskunde en Natuurwetenschappen

This thesis described the development of novel scanning tunneling microscopy techniques to investigate strongly correlated electronic states in quantum matter.

Ariadne Schmidt, Isabelle Devos and Julie de Groot provide you with refreshing insights concerning the study on urban singles in the period between 1200 and 1900.

Promotor: Prof.dr. J.M. van Ruitenbeek, Prof.dr. R.M. Tromp

Promotor: Prof.dr. T. Schmidt, Co-promotor: Dr. ir. S. J.T. van Noort

In this thesis, we describe the latest advances in SQUID-detected Magnetic Resonance Force Microscopy (MRFM).

In this thesis we use Josephson and noise scanning tunneling microscopy for the study of conventional, unconventional (iron-based) and disordered superconductors. On the one hand, Josephson scanning tunneling microscopy allows us to directly visualize the superfluid density with high spatial resolut…

In this thesis, we show how MRFM can usefully contribute to the field of condensed-matter.

Our DNA molecules are packaged by proteins in compact structures. The aim of this project is to understand how modern gene editing techniques nevertheless get access to their target in the DNA.

The dissertation describes TEM experiments on heterogeneous catalysts.

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.

We explore the possibilities to combine magnetic resonance techniques with atomic force microscopy together in a single microscope: the MRI-AFM, also called Magnetic Resonance Force Microscopy (MRFM).

Nucleoid associated proteins maintain the architecture of the bacterial chromosome and regulate gene expression, hinting that their role as transcription factors may involve local three-dimensional chromosome re-modelling.

High throughput microscopy

Microbial Sciences' contribution to the Bioactive Molecules research theme is to discover new bioactive molecules and enzymes and unravel their mechanisms of action, regulatory networks, and the (bio)synthetic pathways required for their production.

Even a small quantum computer should be able to simulate exactly the properties and behaviour of new molecules. This would take chemistry to an entirely new level. Better solar panels, more powerful batteries, saving lots of energy in the chemical industry: the applications have the potential to transform…

Deficiency of glucocerebrosidase (GBA) underlies Gaucher disease, a common lysosomal storage disorder. Carriership for Gaucher disease has recently been identified as major risk for parkinsonism. Presently, no method exists to visualize active GBA molecules in situ. We here report the design, synthesis…

Promotores: Prof.dr. H.P. Spaink & Prof.dr. P.C.W. Hogendoorn, Co-promotor: Dr. M.J.M. Schaaf

Plant Sciences' contribution to the Bioactive Molecules research theme is to identify new plant bioactive molecules, and unravel their mechanisms of action in plant development or health, and the regulatory networks and (bio)synthetic pathways required for their production.

Promotores: Prof.dr. C.U. Keller, Prof.dr. H.C. Gerritsen

Leiden physicists have managed to detect a single molecule called dibenzoterrylene in a new crystal, and found that it is a candidate component for a quantum network. Future quantum computers will need such a network to work together while maintaining their advantages. Publication in ChemPhysChem jo…

Promotor: T.H. Oosterkamp