English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Journal Article

Modulating vesicle adhesion by electric fields

MPS-Authors
/persons/resource/persons133119

Steinkühler,  Jan
Rumiana Dimova, Theorie & Bio-Systeme, Max Planck Institute of Colloids and Interfaces, Max Planck Society;

/persons/resource/persons131271

Agudo-Canalejo,  Jaime
Reinhard Lipowsky, Theorie & Bio-Systeme, Max Planck Institute of Colloids and Interfaces, Max Planck Society;

/persons/resource/persons121584

Lipowsky,  Reinhard
Reinhard Lipowsky, Theorie & Bio-Systeme, Max Planck Institute of Colloids and Interfaces, Max Planck Society;

/persons/resource/persons121236

Dimova,  Rumiana
Rumiana Dimova, Theorie & Bio-Systeme, Max Planck Institute of Colloids and Interfaces, Max Planck Society;

External Resource
No external resources are shared
Fulltext (public)

2351362.pdf
(Publisher version), 2MB

Supplementary Material (public)

2351362_supp1.pdf
(Supplementary material), 498KB

2351362_supp2.pdf
(Supplementary material), 2MB

Citation

Steinkühler, J., Agudo-Canalejo, J., Lipowsky, R., & Dimova, R. (2016). Modulating vesicle adhesion by electric fields. Biophysical Journal, 111(7), 1454-1464. doi:10.1016/j.bpj.2016.08.029.


Cite as: http://hdl.handle.net/11858/00-001M-0000-002B-B685-F
Abstract
We introduce an experimental setup for modulating adhesion of giant unilamellar vesicles to a planar substrate. Adhesion is induced by the application of an external potential to a transparent indium tin oxide-coated electrode (the substrate), which enables single-vesicle studies. We demonstrate tunable and reversible adhesion of negatively charged vesicles. The adhesion energy at different potentials is calculated from the vesicle shape assessed with confocal microscopy. Two approaches for these estimates are employed: one based on the whole contour of the vesicle and a second based on the contact curvature of the membrane in the vicinity of the substrate. Both approaches agree well with each other and show that the adhering vesicles are in the weak adhesion regime for the range of explored external potentials. Using fluorescence quenching assays, we detect that, in the adhering membrane segment, only the outer bilayer leaflet of the vesicle is depleted of negatively charged fluorescent lipids, while the inner leaflet remains unaffected. We show that depletion of negatively charged lipids is consistent Poisson-Boltzmann theory, taking into account charge regulation from lipid mobility. Finally, we also show that lipid diffusion is not significantly affected in the adhering membrane segment. We believe that the approaches introduced here for modulating and assessing vesicle adhesion have many potential applications in the field of single-vesicle studies and research on membrane adhesion.