Solvent-free coarse-grained lipid model for large-scale simulations

TL;DR

This paper introduces a solvent-free coarse-grained lipid model that efficiently simulates large-scale membrane behaviors, capturing key physical properties and phase transitions with adjustable parameters.

Contribution

The novel model combines a spherical particle and orientation vector to simulate lipid membranes without explicit solvent, enabling large-scale and flexible membrane simulations.

Findings

Successfully reproduces bilayer structure and properties

Demonstrates membrane stability and phase transitions

Allows tuning of membrane physical parameters

Abstract

A coarse-grained molecular model, which consists of a spherical particle and an orientation vector, is proposed to simulate lipid membrane on a large length scale. The solvent is implicitly represented by an effective attractive interaction between particles. A bilayer structure is formed by orientation-dependent (tilt and bending) potentials. In this model, the membrane properties (bending rigidity, line tension of membrane edge, area compression modulus, lateral diffusion coefficient, and flip-flop rate) can be varied over broad ranges. The stability of the bilayer membrane is investigated via droplet-vesicle transition. The rupture of the bilayer and worm-like micelle formation can be induced by an increase in the spontaneous curvature of the monolayer membrane.