Fluctuation spectroscopy of giant unilamellar vesicles using confocal and phase contrast microscopy

TL;DR

This paper compares fluctuation spectroscopy measurements of giant unilamellar vesicles using confocal and phase contrast microscopy, confirming consistent bending rigidity values and discussing potential sources of discrepancy.

Contribution

It provides a direct comparison of two microscopy techniques for fluctuation spectroscopy and analyzes factors affecting measurement accuracy.

Findings

Both microscopy methods yield consistent bending modulus values.

Factors influencing measurement discrepancies are identified and discussed.

The study validates fluctuation spectroscopy as a reliable method across different imaging techniques.

Abstract

A widely used method to measure the bending rigidity of bilayer membranes is fluctuation spectroscopy, which analyses the thermally-driven membrane undulations of giant unilamellar vesicles recorded with either phase-contrast or confocal microscopy. Here, we analyze the fluctuations of the same vesicle using both techniques and obtain consistent values for the bending modulus. We discuss the factors that may lead to discrepancies.