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bioRxiv · 10.1101/2025.08.02.668278

A Microfluidic Platform for Whole-Membrane Integrity Profiling in Live Neuronal Cells

Abstract

Structural and functional compromise of the cellular membrane are central mechanisms in the pathogenesis of numerous diseases, including neurodegenerative disorders such as Alzheimers and Parkinsons disease. However, existing techniques for assessing membrane integrity often lack the ability to provide dynamic, whole-cell measurements and are limited to localized damage detection or population-level analysis. There is a growing need for methods capable of monitoring membrane integrity over time at the single-cell level and across the entire membrane surface. In this study, we present a microfluidic platform for real-time, label-free assessment of membrane integrity by analyzing dielectric properties. We apply this system to investigate how different aggregated forms of -Synuclein (aSyn), a protein that plays a central role in the pathogenesis of Parkinsons disease and disrupts neuronal membranes. Our platform integrates electrokinetic microdevices with 3D microelectrodes and imaging, enabling continuous analysis of up to 30 live neuronal cells per hour under flow. By measuring electrorotation responses, we quantify changes in plasma membrane capacitance in response to monomeric, oligomeric, and fibrillar aSyn. This approach allows direct, time-resolved comparison of membrane-disruptive effects across different aSyn conformations with single-cell resolution and whole-membrane sensitivity.

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BibTeXRIS

Ryser, T., Krichene, A., Marchi, N., Rodriguez Espinal, F., Mahul-Mellier, A.-L., Lashuel, H. A., Guiducci, C.. 2025-08-02. A Microfluidic Platform for Whole-Membrane Integrity Profiling in Live Neuronal Cells. https://doi.org/10.1101/2025.08.02.668278

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