Person
Halil Ibrahim Okur
This person is no longer with EPFL
Related publications (21)
Transient domains of ordered water induced by divalent ions lead to lipid membrane curvature fluctuations
Sylvie Roke, Orly Bagunu Tarun, Halil Ibrahim Okur
Cations influence the electrostatic, chemical and mechanical properties of lipid bilayers. Here, label-free second harmonic microscopy shows that cation-induced transient ordering of water also plays a role in driving membrane curvature fluctuations, linki ...
NATURE PUBLISHING GROUP2020On the stability and necessary electrophoretic mobility of bare oil nanodroplets in water
Sylvie Roke, Saranya Pullanchery Sankara Narayanan, Halil Ibrahim Okur, Hilton Barbosa De Aguiar, Sergey Kulik
Hydrophobic oil droplets, particles, and air bubbles can be dispersed in water as kinetically stabilized dispersions. It has been established since the 19th century that such objects harbor a negative electrostatic potential roughly twice larger than the t ...
AMER INST PHYSICS2020Chemistry of Lipid Membranes from Models to Living Systems: A Perspective of Hydration, Surface Potential, Curvature, Confinement and Heterogeneity
Sylvie Roke, Orly Bagunu Tarun, Halil Ibrahim Okur
Lipid membranes provide diverse and essential functions in our cells relating to transport, energy harvesting and signaling. This variety of functions is controlled by the molecular architecture, such as the presence of hydrating water, specific chemical c ...
2019The Diverse Nature of Ion Speciation at the Nanoscale Hydrophobic/Water Interface
Sylvie Roke, Halil Ibrahim Okur, Evangelia Zdrali
Many biological systems are composed of nanoscale structures having hydrophobic and hydrophilic groups adjacent to one another and in contact with aqueous electrolyte solution. The interaction of ions with such structures is of fundamental importance. Alth ...
AMER CHEMICAL SOC2019Specific Ion Effects at the Interface of Nanometer-Sized Droplets in Water: Structure and Stability
Sylvie Roke, Halil Ibrahim Okur, Evangelia Zdrali
The interaction of ions with interfaces influences numerous processes in chemistry, physics, and biology, while different ion species behave differently at hydrophobic or hydrophilic interfaces. Despite its importance, ion specificity and its relation to s ...
2019Polyelectrolytes induce water-water correlations that result in dramatic viscosity changes and nuclear quantum effects
Sylvie Roke, Jan Dedic, Halil Ibrahim Okur
Ions interact with water via short-ranged ion-dipole interactions. Recently, an additional unexpected long-ranged interaction was found: The total electric field of ions influences water-water correlations over tens of hydration shells, leading to the Jone ...
American Association for the Advancement of Science (AAAS)2019Determination and evaluation of the nonadditivity in wetting of molecularly heterogeneous surfaces
Francesco Stellacci, Michele Ceriotti, Sylvie Roke, Quy Ong Khac, Halil Ibrahim Okur, David Mark Wilkins, Zhi Luo, Anna Murello, Filip Kovacik
The interface between water and folded proteins is very complex. Proteins have "patchy" solvent-accessible areas composed of domains of varying hydrophobicity. The textbook understanding is that these domains contribute additively to interfacial properties ...
PNAS2019Membrane–Protein–Hydration Interaction of α-Synuclein with Anionic Vesicles Probed via Angle-Resolved Second-Harmonic Scattering
Sylvie Roke, Jan Dedic, Halil Ibrahim Okur
Amyloid formation of the protein α-synuclein promotes neurodegeneration in Parkinson's disease. The normal function of α-synuclein includes synaptic vesicle transport and fusion, and the protein binds strongly to negatively charged vesicles in vitro. Here, ...
2019Hydration mediated interfacial transitions on mixed hydrophobic/hydrophilic nanodroplet interfaces
Sylvie Roke, Nikolay Smolentsev, Halil Ibrahim Okur, Rüdiger Scheu, Filip Kovacik
Interfacial phase transitions are of fundamental importance for climate, industry, and biological processes. In this work, we observe a hydration mediated surface transition in supercooled oil nanodroplets in aqueous solutions using second harmonic and sum ...
AMER INST PHYSICS2018Temperature dependence of water-water and ion-water correlations in bulk water and electrolyte solutions probed by femtosecond elastic second harmonic scattering
Sylvie Roke, Nathan Dupertuis, Yixing Chen, Halil Ibrahim Okur
The temperature dependence of the femtosecond elastic second harmonic scattering (fs-ESHS) response of bulk light and heavy water and their electrolyte solutions is presented. We observe clear temperature dependent changes in the hydrogen (H)-bond network ...
2018