Thermo-mechanic-electrical coupling in phospholipid monolayers near the critical point

TL;DR

This paper demonstrates that lipid monolayers exhibit coupled thermo-mechanic-electrical properties near their critical point, enabling predictions of electrical and thermal behaviors from mechanical measurements with increasing accuracy close to criticality.

Contribution

It introduces a theoretical framework linking mechanical, thermal, and electrical properties of lipid monolayers near the critical point using fluctuation theory.

Findings

Linear relationships between entropy, area, and charge.

Couplings allow predicting electrical and thermal properties from mechanical data.

Prediction accuracy improves near the critical temperature.

Abstract

Lipid monolayers have been shown to represent a powerful tool in studying mechanical and thermodynamic properties of lipid membranes as well as their interaction with proteins. Using Einstein's theory of fluctuations we here demonstrate, that an experimentally derived linear relationship both between transition entropy S and area A as well as between transition entropy and charge q implies a linear relationships between compressibility \kappa_T, heat capacity c_\pi, thermal expansion coefficient \alpha_T and electric capacity CT. We demonstrate that these couplings have strong predictive power as they allow calculating electrical and thermal properties from mechanical measurements. The precision of the prediction increases as the critical point TC is approached.