STI – A nonlinear optical view of proton transport and proton coupled transport

Two PhD student positions are available at the Laboratory for fundamental BioPhotonics (LBP) at the École Polytechnique Fédérale de Lausanne (EPFL), Switzerland.

The Projects

Proton transfer is crucial in numerous biological and chemical processes, e.g. in cellular proton pumps or in hydrogen fuel cells. Even though the empirical study of H+ ions began with the origin of chemistry, many details of the proton transfer mechanism are still unresolved and understanding the way in which confined water mediates proton dynamics remains a fundamental challenge in chemistry and biochemistry. Newly developed label-free and charge-sensitive dynamic imaging techniques of lipid membrane hydration, and the hydration of active sites now offer the possibility to explore the interplay between structural features of interfacial hydration and proton migration on the molecular level and on sub-second time scales.

To aid the understanding of proton transport on multiple levels, within the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement, H2020-MSCA-ITN-2019 – 860592 – PROTON, we are looking for two PhD positions. The two PhD positions have the following objectives:

  1. The hydrated interfacial layer of lipid membranes plays an important role in the distribution and transport of ions. The structure of water and ions are intimately related and how they interact precisely with the membrane and its constituents is not known, mainly due to a lack of sufficiently sensitive noninvasive spectroscopic / microscopic tools. To quantify the molecular level structural of the hydrated interfacial layer of membranes and changes therein when proton transport occurs, we apply our newly developed high throughput nonlinear imaging and light scattering techniques that allow to probe the interactions of interfacial lipids, water and ions.
  2. Ion channels are the most important membrane related signaling element in cells. They are generally studied using a structural biology approach, which means there is often some information about passive structure (e.g. in the crystalline form), but not during ion channel activity. By spatiotemporal and spectroscopic mapping of water molecules and ions in and near active or passive ion channels, using second harmonic and sum frequency scattering of ion channels in (liposome) membranes, we will aim to determine the molecular structure of the water, as well as the conformation of the channels and the adjacent membrane molecules.

The Candidate

This research has many interdisciplinary aspects that demand a highly motivated candidate with strong analytical abilities, and someone who is able to think out of the box. The diverse aspects of the project require a backgrounds that includes photonics, physics, physical chemistry, material science or electrical engineering. Experience in nonlinear optics / microscopy, or ultrafast (vibrational) spectroscopy is another asset. EPFL offers excellent working conditions and a state-of-the-art infrastructure in a highly dynamic and international environment at the forefront of research.

The Application Procedure

Applications should include a motivation letter, detailed CV, transcripts of diplomas as well as three letters of reference. In conjunction to the application the candidate must be accepted by one of the doctoral schools: photonics, materials science, or bioengineering (

More Information & contact

Work conditions are in accordance with H2020 guidelines and more information about the project framework can be found at: Feel free to contact us in case of further questions. Contact: [email protected]