Dynamics of shape fluctuations of quasi-spherical vesicles revisited

TL;DR

This paper develops a comprehensive theoretical framework for understanding the dynamics of shape fluctuations in giant quasi-spherical vesicles, offering new interpretations of membrane constants and predictions for experimental validation.

Contribution

It introduces a systematic theoretical formulation and a new interpretation of phenomenological constants in membrane dynamics, improving upon previous models.

Findings

Analytical description of vesicle shape fluctuation dynamics

New interpretation of membrane phenomenological constants

Predictions for system-dependent relaxation behaviors

Abstract

In this paper, the dynamics of spontaneous shape fluctuations of a single, giant quasi-spherical vesicle formed of a single lipid species is revisited theoretically. A coherent physical theory for the dynamics is developed based on a number of fundamental principles and considerations and a systematic formulation of the theory is also established. From the systematic theoretical formulation, an analytical description of the dynamics of shape fluctuations of quasi-spherical vesicles is derived. In particular, in developing the theory we have made a new interpretation of some of the phenomenological constants in a canonical continuum description of fluid lipid-bilayer membranes and shown the consequences of this new interpretation in terms of the characteristics of the dynamics of vesicle shape fluctuations. Moreover, we have used the systematic formulation of our theory as a framework against which we have discussed the previously existing theories and their discrepancies. Finally, we have made a systematic prediction about the system-dependent characteristics of the relaxation dynamics of shape fluctuations of quasi-spherical vesicles with a view of experimental studies of the phenomenon and also discussed, based on our theory, a recently published experimental work on the topic.