By detecting the tiny forces between a micrometer sized magnet and the spins of hydrogen nuclei, we can do MRI with a volume resolution that is approximately 12 orders of magnitude better than a conventional MRI.  

Promotor: Prof.dr. J.P. Abrahams, Prof.dr. M. van Heel

This thesis aimed to investigate the impact of exposure dynamics, relative contributions of ENPs(particle) and ENPs(ion), and dosing regimens on the toxicity of ENPs varying in different physico-chemical properties, on the composition and functioning of soil microbial communities.

Promotor: Prof.dr. T. Hankemeier, Prof.dr. J.C.T. Eijkel (Twente University)

Metal complexes and 2D materials like graphene were combined to produce structures that can function as sensors.

From filtering UV light in sun cream to preventing perspiration odour in socks and sterilising fridges and washing machines. The use of nanoparticles in products is increasing. But what is the impact of these miniscule particles on the environment?

Individual molecules are extremely hard to see through feeble fluorescence. Tiny gold nanorods serve as new antennas to intensify their signal 500 times. Publication on 24 February in Angewandte Chemie.

'Quality Nano' funded research of the Institute of Environmental Sciences to work in Exeter University for 20 working days, which allows the institute to access highly advanced equipment needed for evaluation the toxicity of nanoparticles.

Promotor: J.P. Abrahams, Co-promotor: T. Grüne

Scattering of light in the presence of nano-structured materials, i.e. with features in the order of the wavelength of the light or smaller, reveals details of how light interacts with matter at the nanoscale.

PhD Defence

Bachelor projects are available in

PhD Defence

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

1. To what extent do metallic NPs added to soil extractions change the activity, abundance, or community composition of microbes? 2. How do the effects of metallic NPs on soil microbes differ from the effects of the ions shedding from corresponding NPs?

Membrane proteins and membrane interactions of proteins are studied by spin label EPR. Intact, native membranes, vesicles of all sizes and nano-disks can be investigated, because the size of the object does not matter in EPR. Whereas solution NMR is limited to micelles (a few nm in diameter), by EPR…

In this project innovative technology for photovoltaics cells is developed and analysis of ecological and health related risks are explicitly accounted for.

Gold nanoparticles show surprisingly strong interactions with light in the visible range, which can be divided into scattering, absorption, and photoluminescence.

PhD Defence

A new microtonal approach of the bass clarinet, to further develope the instrument’s capability to produce not only exact quartertones, but also smaller units.

The aim is to discover where differently shaped metal nanoparticles distributes in Danio rerio, linking the distribution with genomic responses and so come up with a Mode of Action.

Develop EPR instrumentation and methodology to investigate intrinsically disordered proteins (IDPs).

Promotor: D. Bouwmeester, Co-promotor: D. Kraft

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

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

Promotor: W. Jiskoot, Co-promotor: A. Hawe

With a pioneering project like the quantum computer, it’s a good idea not to place all your bets on a single horse. In Leiden’s Quantum Optics research group, instead of working on a Majorana-based qubit, people are working on a qubit based on an ‘artificial atom’. If that becomes the basis of the quantum…

A couple of years ago, theoretical physicist Carlo Beenakker tracked down the Majorana particles and inspired Leo Kouwenhoven from TU Delft to try to create them in a superconducting nano-structure. He succeeded in doing so in 2012, and the news made headlines around the world. But a lot of work still…

In Quantum mechanics, particles can be in multiple positions simultaneously. Yet, when a measurement is made, the particle is found only in one place. Technology has come to a point where we may design experiments that will tell us how.

Poly(lactic-co-glycolic acid) (PLGA) particles have been extensively studied as biodegradable delivery system to improve the potency and safety of protein-based vaccines. In this study we analyzed how the size of PLGA particles, and hence their ability to be engulfed by dendritic cells (DC), affects…

On 18 June 2019, Neta Palkovitz Menashy defended her thesis 'Regulating a Revolution: Small Satellites and the Law of Outer Space'. The doctoral research was supervised by Prof. dr. P.M.J. Mendes de Leon and Prof. dr. G. Molier.

Is it possible to successfully design self-assembling nano-scale protein skeletons for use as a vaccine platform?

A lot of our research is performed at temperatures close to absolute zero, among other reasons because this increases the sensitivity of the measurements. 

Master projects are available in

Assessing the risks of engineered nanomaterials (ENMs) solely on the basis of experimental assays is time-consuming, resource intensive, and constrained by ethical considerations (such as the principles of the 3Rs of animal testing). The adoption of computational toxicology in this field is a high p…

Research at the department of Environmental Biology

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.

This research programme aims to increase the scientific understanding of how current and emerging anthropogenic threats affect biodiversity and ecosystem services to facilitate strategic management of natural resources. To this end, we address urgent challenges in relation to the mechanisms involved…

Twenty years from now, the world population is estimated to be around 8.7 billion people, compared to the current 7.3 billion. In combination with the improvements in living standards and the corresponding growth in consumption, this will result in an enormous increase in the demand for food, consumables,…

Former PhD, Bachelor and Master students of the Van Exter Lab

Twenty years from now, the world population is estimated to be around 9 billion people (now 7.8 billion). In combination with the improvements in living standards and the corresponding growth in consumption, this will result in an enormous increase in the demand for food, consumables, water and energy.…

What are the principles of genome folding and dynamics in bacteria?

Coordination chemistry is the chemistry of metal atoms

How do plants lure microscopically small 'support teams' into their roots for protection against diseases? And what functions are activated in the microbes and the plants?

The quantum nature of matter and light has grown into a broad and fruitful research field for theorists and experimentalists alike. It combines foundational research with toward applications, the most well known of which is the quantum computer.

Our group explores the larger domain of quantum measurement. In particular we investigate two themes that are closely connected: The detection of specially prepared quantum states of light and understanding and characterizing quantum photon detectors.

How to make a quantitative assessment of the relative contribution to toxicity of ions and particles? Is the toxicity of nanoparticles related to their size or shape? Which physicochemical property of nanoparticles is an appropriate dose metric of nanoparticles?

Leiden researchers have carried out successful tests using a new method of packaging a cancer vaccine in nano-particles. The new vaccine has induced a strong immune reaction in mice. The researchers believe that this method can make an important contribution to the treatment of cancer. Their findings…

Superconducting devices such as SQUIDS (Superconducting Quantum Interferometry Device) can perform ultra-sensitive measurements of magnetic fields. Leiden physicsts invented a method to 3D-print these and other superconducting devices in minutes.