Laboratory for Fundamental BioPhotonics

Welcome to the LBP!


Recent Results

Spatiotemporal Imaging of Water in Operating Voltage-Gated Ion Channels Reveals the Slow Motion of Interfacial Ions

O. B. Tarun, M. Y. Eremchev, A. Radenovic, S. Roke

Nano Lett. 2019, 19, 11, 7608-7613 – DOI: 10.1021/acs.nanolett.9b02024


Surface Characterization of Colloidal Silica Nanoparticles by Second Harmonic Scattering: Quantifying the Surface Potential and Interfacial Water Order

A. Marchioro, M. Bischoff, C. Lütgebaucks, D. Biriukov, M. Předota, S. Roke

J. Phys. Chem. C 2019, 123, 33, 20393-20404 – DOI: 10.1021/acs.jpcc.9b05482


Specific Ion Effects at the Interface of Nanometer-Sized Droplets in Water: Structure and Stability

E. Zdrali, H. I. Okur, S. Roke

J. Phys. Chem. C 2019, 123, 27, 16621-16630 – DOI: 10.1021/acs.jpcc.9b01001



Membrane water for probing neuronal membrane potentials and ionic fluxes at the single cell level

M. E. P. Didier, O. B. Tarun, P. Jourdain, P. Magistretti and S. Roke

Nature Comm. (2018), 9, 5287. – DOI: 10.1038/s41467-018-07713-w

Our recent Nature Communication article is featured on EPFL main page (English and French), and many popular scientific websites; EurekAlert!, The Medical News, Nanowerk,, Science Daily, Long Room, Medical News, and Health Canal.


Imaging of water molecules inside a pore and at an interface with SH microscopy:

  • Label-free and charge-sensitive dynamic imaging of lipid membrane hydration on millisecond time scales.

Orly B. Tarun, Christof Hannesschlager, Peter Pohl, Sylvie Roke

PNAS (2018), 115, 16, 4081-4086.        DOI: 10.1073/pnas.1719347115

Our recent PNAS paper is featured on EPFL main page (English and French), and many popular scientific websites; sciencedaily, sciencenewsline,, kynplex, techexplorist, numerons, myhealthexercise, and innovations-report.

  • The Jones-Ray effect is not caused by surface active impurities.

Halil I. Okur, Chad I. Drexler, Eric Tyrode, Paul S. Cremer, Sylvie Roke

Journal of Physical Chemistry Letters, 2018, 9 (23), 6739-6743        DOI: 10.1021/acs.jpclett.8b02957

  • Interaction of oil and lipids in freestanding lipid bilayer membranes studied with label-free high-throughput wide-filed second-harmonic microscopy.

Orly B. Tarun, Maksim Y. Eremchev, Sylvie Roke

Langmuir, 2018, 34 (38), 11305-11310       DOI: 10.1021/acs.langmuir.8b01790

  • Temperature dependence of water-water and ion-water correlations in bulk water and electrolyte solutions probed by femtosecond elastic second harmonic scattering.

Yixing Chen, Nathan Dupertuis, Halil I. Okur, Sylvie Roke

Journal of Chemical Physics 148, 222835 (2018)        DOI: 10.1063/1.5023343

  • Comment On “Water-water correlations in electrolyte solutions probed by hyper-Rayleigh scattering”.

Yixing Chen, Halil I. Okur, Nathan Dupertuis, Jan Dedic, David M. Wilkins, Michele Ceriotti, Sylvie Roke

J. Chem Phys. 149, 167101 (2018)              DOI: 10.1063/1.5023579

  • Polycation Interactions with Zwitterionic Phospholipid Monolayers on Oil Nanodroplets Suspensions in Water (D2O) Probed by Sum Frequency Scattering.

Laura L. Olenick, Julianne M. Troiano, Nikolay Smolentsev, Paul E. Ohno, Sylvie Roke, Franz M. Geiger

J. Phys. Chem. B. 2018, 122, 19, 5046-5056      DOI: 10.1021/acs.jpcb.8b00309

  • Zwitterionic and charged lipids form remarkably different structures on nanoscale oil droplets in aqueous solution.

Yixing Chen, Halil I. Okur, Cornelis Lütgebaucks, Sylvie Roke

Langmuir, 2018, 34(3), pp 1042-1050  DOI: 10.1021/acs.langmuir.7b02896

  • Optical imaging of surface chemistry and dynamics in confinement.

Carlos Macias-Romero, Igor Nahalka, Halil I. Okur, Sylvie Roke

Science (2017) eaal4346, DOI:10.1126/science.aal4346

Our recent Science paper is featured on EPFL main page (english and french), and many popular scientific websites;

  • The Molecular Mechanism of Nanodroplet Stability.

Evangelia Zdrali, Yixing Chen, Halil I. Okur, David M. Wilkins and Sylvie Roke

ACS Nano, 2017, 11(12), pp12111-12120 DOI: 10.1021/acsnano.7b05100

  • The interfacial structure of water droplets in a hydrophobic liquid.

Nikolay Smolentsev, Wilbert J. Smit, Huib J. Bakker, Sylvie Roke

Nature Communications 8, 15548 (2017) DOI: 10.1038/ncomms15548

Our Nature Communications article was featured on EPFL main webpage (english and french), IBI webpage, AMOLF (english and dutch) and FOM websites as well as many popular scientific websites:,,,,,,,,,, and

  • The Jones-Ray Effect Reinterpreted: Surface Tension Minima of Low Ionic Strength Electrolyte Solutions are caused by Electric Field Induced Water-Water Correlations.

Halil I. Okur, Yixing Chen, David M. Wilkins, and Sylvie Roke

Chem. Phys. Lett. 684, (2017), 433-442 DOI:10.1016/j.cplett.2017.06.018

  • Interfacial Structure and Hydration of 3D Lipid Monolayers in Aqueous Solution.

Halil I. Okur, Yixing Chen, Nikolay Smolentsev, Evangelia Zdrali, and Sylvie Roke

J. Phys. Chem. B. 2017, 121 (13), pp 2808-2813              DOI: 10.1021/acs.jpcb.7b00609

  • Orientational ordering of water in extended hydration shells of cations is ion-specific and is correlated directly with viscosity and hydration free energy

Yixing Chen, Halil I. Okur, Chungwen Liang and Sylvie Roke

Phys. Chem. Chem. Phys., 2017, 19, 24678-24688             DOI: 10.1039/C7CP03395H

  • Characterization of the interface of binary mixed DOPC:DOPS liposomes in water: The impact of charge condensation.

Cornelis Lütgebaucks, Carlos Macias-Romero and Sylvie Roke

J. Chem. Phys. 146, 044701 (2017)                DOI: 10.1063/1.4974084

  • Aqueous Nanoscale Systems

Sylvie Roke

CHIMIA International Journal for Chemistry 71, 278-282, (2017)              DOI:

  • Communication: Mean-field theory of water-water correlations in electrolyte solutions

David M. Wilkins, David E. Manolopoulos, Sylvie Roke, Michele Ceriotti

The Journal of Chemical Physics 146 (18), 181103 (2017)               DOI:

  • Generalized expressions for hyper-Rayleigh scattering from isotropic liquids

Yixing Chen, Sylvie Roke


  • Solvent fluctuation and nuclear quantum effects modulate the molecular hyperpolarizability of water

Chungwen Liang, Gabriele Tocci, David M. Wilkins, Andrea Grisafi, Sylvie Roke, Michele Ceriotti

Physical Review B, 96, 041407 (2017)             DOI: 10.1103/PhysRevB.96.041407