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Updated: Feb 26, 2026
11:55
Membrane Transport Processes Analyzed by a Highly Parallel Nanopore Chip System at Single Protein Resolution
Published on: August 16, 2016
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Permeability modes in fluctuating lipid membranes with DNA-translocating pores
L H Moleiro1, M Mell2, R Bocanegra3
13BHub, Biophysics for Biotechnology and Biomedicine, Departamento de Química Física I, Universidad Complutense, Ciudad Universitaria s/n, 28040 Madrid, Spain; Physikalische Chemie I, Univeristät Bayreuth, Universitätsstraße 30, D95447 Bayreuth, Germany; Physikalische und Biophysikalische Chemie I, Universität Bielefeld, Universitätsstraße 25, D33615 Bielefeld, Germany.
Advances in Colloid and Interface Science
|July 25, 2017
Summary
Large membrane pores induce active-like fluctuations due to solute transport, demonstrating non-equilibrium behavior in lipid vesicles. This finding has bio-nano-technology applications for gene delivery.
Area of Science:
- Biophysics
- Soft Matter Physics
- Nanotechnology
Background:
- Membrane pores influence permeation dynamics and elasticity.
- Theoretical models predict active-like behavior in permeable membranes due to enhanced fluctuations.
- Large pores transporting macromolecules offer a unique system to study these phenomena.
Purpose of the Study:
- To experimentally analyze active shape fluctuations in lipid vesicles with large macromolecular pores.
- To investigate the relationship between pore density, mechanical properties, and permeability rates.
- To demonstrate the non-equilibrium nature of membrane fluctuations under permeation.
Main Methods:
- Experimental analysis of active shape fluctuations in lipid vesicles with engineered large pores.
- Quantitative comparison of experimental results with theoretical predictions.
- Detection and analysis of individual permeation events from fluctuation time-series.
Main Results:
- Experimental data quantitatively agree with theoretical predictions.
- Active fluctuations show a strong dependence on membrane pore density.
- Permeation events exhibit a stochastic distribution consistent with shot-noise.
Conclusions:
- Forced transport through large membrane pores drives non-equilibrium active shape fluctuations.
- The study demonstrates the non-equilibrium character of membrane fluctuations even with passive pores.
- The findings suggest potential applications in bio-nano-technology, such as active membrane DNA-pores for gene delivery.
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