Lipoprotein diffusion in dense yolk plasma is governed by softness, hydrodynamics, and caging: Insights from MHz-XPCS
Abstract
Low-density lipoproteins (LDLs) are central to nutrient transport in egg yolk and have emerged as natural nanocarriers for drug delivery. Their biological function critically depends on mobility within densely crowded environments, yet the mechanisms governing their motion remain elusive, largely because conventional techniques cannot access the relevant microsecond timescales. Here, we employ megahertz X-ray photon correlation spectroscopy at the European X-ray Free Electron Laser facility to resolve LDL dynamics in native yolk-plasma. This approach reveals transient caging and memory effects and shows that the combined influence of particle softness and hydrodynamic coupling slows diffusion by nearly two orders of magnitude compared to dilute solutions. However, this reduction could not be scaled with an increase in macroscopic viscosity obtained from rheometry, indicating deviations from the Stokes–Einstein relation. Despite this slowdown, yolk-plasma remains a “sluggish yet liquid state”, balancing dense packing and the fluidity required for lipid release during embryonic development. These results establish a quantitative framework connecting microstructure, hydrodynamics, and transport in crowded soft-matter systems, with implications for developmental biology and nanomedicine.
Article Details
Journal Info
Proceedings of the National Academy of Sciences
National Academy of Sciences
Authors (30)
Nimmi Das Anthuparambil
Department Physik, Universität Siegen
Michelle Dargasz
Department Physik, Universität Siegen
Sonja Timmermann
Department Physik, Universität Siegen
Anita Girelli
Department of Physics, AlbaNova University Center, Stockholm University
Sebastian Retzbach
Institut für Angewandte Physik, Universität Tübingen
Johannes Möller
European X-Ray Free-Electron Laser Facility
Wonhyuk Jo
European X-Ray Free-Electron Laser Facility
Agha Mohammad Raza
Department Physik
Aliaksandr Leonau
Department Physik, Universität Siegen
James Wrigley
European X-Ray Free-Electron Laser Facility
Frederik Unger
Department Physik, Universität Siegen
Maddalena Bin
Department of Physics, AlbaNova University Center, Stockholm University
Prince Prabhu Rajaiah
Institute for Biochemistry and Molecular Biology
Iason Andronis
Department of Physics, AlbaNova University Center, Stockholm University
William Chèvremont
The European Synchrotron, ESRF, 71 Avenue des Martyrs, CS40220, Grenoble 38043, France
Jörg Hallmann
European X-Ray Free-Electron Laser Facility
Angel Rodriguez-Fernandez
European X-Ray Free-Electron Laser Facility
Jan-Etienne Pudell
European X-Ray Free-Electron Laser Facility
Felix Brausse
European X-Ray Free-Electron Laser Facility
Ulrike Boesenberg
European X-Ray Free-Electron Laser Facility
Mohamed Youssef
European X-Ray Free-Electron Laser Facility
Roman Shayduk
European X-Ray Free-Electron Laser Facility
Rustam Rysov
European X-Ray Free-Electron Laser Facility
Anders Madsen
European X-Ray Free-Electron Laser Facility
Felix Lehmkühler
Deutsches Elektronen-Synchrotron
Michael Paulus
Fakultät Physik/DELTA
Fajun Zhang
Institut für Angewandte Physik, Universität Tübingen
Fivos Perakis
Department of Physics, AlbaNova University Center, Stockholm University
Frank Schreiber
Institut für Angewandte Physik, Universität Tübingen
Christian Gutt
Department Physik, Universität Siegen