Vesicle formation induced by thermal fluctuations

TL;DR

This paper demonstrates that increasing temperature can promote vesicle formation in membranes, revealing a phase transition influenced by curvature, energy terms, and chemical potential, with implications for understanding membrane dynamics.

Contribution

It introduces a membrane phase field model incorporating Gaussian curvature to analyze how temperature induces vesiculation, highlighting the dominant role of Gaussian energy.

Findings

Vesicle formation is promoted by temperature increases.

A phase transition exists between fluctuating and vesiculation phases.

Temperature broadens the conditions for spontaneous vesiculation across geometries.

Abstract

The process of fission and vesicle formation depends on the geometry of the membrane that will split. For instance, a flat surface finds it difficult to form vesicles because of the lack of curved regions where to start the process. Here we show that vesicle formation can be promoted by temperature, by using a membrane phase field model with Gaussian curvature. We find a phase transition between fluctuating and vesiculation phases that depends on temperature, spontaneous curvature, and the ratio between bending and Gaussian moduli. We analysed the energy dynamical behaviour of these processes and found that the main driving ingredient is the Gaussian energy term, although the curvature energy term usually helps with the process as well. We also found that the chemical potential can be used to investigate the temperature of the system. Finally we address how temperature changes the condition for spontaneous vesiculation for all geometries, making it happen in a wider range of values of the Gaussian modulus.