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arXiv · 2403.19922

Ion-Mediated Structural Discontinuities in Phospholipid Vesicles

Judith U. De Mel·Sudipta Gupta·Gerald J. Schneider
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Abstract

Despite intense research, methods for controlling soft matter's spontaneous self-assembly in-to well-defined layers remain a significant challenge. We observed ion-induced structural disconti-nuities of phospholipid vesicles that can be exploited for controlled self-assembly of soft materials. We used dynamic light scattering, zeta-potential measurement, cryo-electron microscopy, small-angle X-ray, and small-angle neutron scattering. All the experimental observations indicate that de-clining solvent quality and increasing osmotic pressure direct lipids to expel preferentially to the inner compartment. Upon reaching a critical concentration, excess lipids can form a new bilayer. This spontaneous self-assembly process causes simultaneous shrinkage of the aqueous core and expansion of the vesicle. This approach opens an intriguing path for controlling the self-assembly of bioinspired colloids, which can also serve as a vehicle to control the polymerization of multilayer polymeric systems.

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Judith U. De Mel, Sudipta Gupta, Gerald J. Schneider. 2024-03-29. Ion-Mediated Structural Discontinuities in Phospholipid Vesicles. https://arxiv.org/abs/2403.19922

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