How Ethanolic Disinfectants Disintegrate Coronavirus Model Membranes: A Dissipative Particle Dynamics Simulation Study

Abstract

We have developed dissipative particle dynamics models for pure dipalmitoylphosphatidylcholine (DPPC), dioleoylphosphatidylcholine (DOPC), and dimyristoylphosphatidylcholine (DMPC) as well as their binary and ternary mixed membranes, as coronavirus model membranes. The stabilities of pure and mixed membranes, surrounded by aqueous solutions containing up to 70 mol % ethanol (alcoholic disinfectants), have been investigated at room temperature. We found that aqueous solutions containing 5–10 mol % ethanol already have a significant weakening effect on the pure and mixed membranes. The magnitude of the effect depends on the membrane composition and the ethanol concentration. Ethanol permeabilizes the membrane, causing its lateral swelling and thickness shrinking and reducing the orientational order of the hydrocarbon tail of the bilayer. The free energy barrier for the permeation of ethanol in the bilayers is considerably reduced by the ethanol uptake. The rupture-critical ethanol concentrations causing the membrane failure are 20.7, 27.5, and 31.7 mol % in the aqueous phase surrounding pure DMPC, DOPC, and DPPC membranes, respectively. Characterizing the failure of lipid membranes by a machine-learning neural network framework, we found that all mixed binary and/or ternary membranes disrupt when immersed in an aqueous solution containing a rupture-critical ethanol concentration, ranging from 20.7 to 31.7 mol %, depending on the composition of the membrane; the DPPC-rich membranes are more intact, while the DMPC-rich membranes are least intact. Due to the tight packing of long, saturated hydrocarbon tails in DPPC, increasing the DPPC content of the mixed membrane increases its stability against the disinfectant. At high DPPC concentrations, where the DOPC and DMPC molecules are confined between the DPPC lipids, the ordered hydrocarbon tails of DPPC also induce order in the DOPC and DMPC molecules and, hence, stabilize the membrane more. Our simulations on pure and mixed membranes of a diversity of compositions reveal that a maximum ethanol concentration of 32 mol % (55 wt %) in the alcohol-based disinfectants is enough to disintegrate any membrane composed of these three lipids.

Faraday Instability in Viscous Fluids Covered with Elastic Polymer Films

“…For provided material and structure of the polymer film, its surface tension and bending stiffness are usually interrelated [57]. In this work, we discuss the effects of surface tension and bending stiffness on the critical value of Faraday instability, respectively, to understand the effect of each parameter on Faraday instability.…”

Supramolecular Self-Assembly of Dipalmitoylphosphatidylcholine and Carbon Nanotubes: A Dissipative Particle Dynamics Simulation Study

“…The DPD interaction parameters for DPPC were recently parameterized in Ref. [ 24 ]. The mapping scheme for CNT is based on a previously developed coarse-grained model of graphene [ 28 , 29 ], in which eight C atoms are regarded as a single bead.…”

“…Therefore, all DPD repulsion parameters for beads of the same type were set to 100, and the cross-interaction parameters were determined according to the Flory−Huggins χ-parameter. In order to avoid dealing with explicit electrostatic interactions in DPD [ 30 ], we slightly increased the repulsion strength between the similarly charged head groups of DPPC ( = 110) to compensate for electrostatic repulsion [ 24 ]. The DPPC bilayer model was previously validated [ 24 ] by simulating a DPPC bilayer immersed in pure water and comparing the area per lipid molecule and the bilayer thickness against experiment and existing atomistic simulation results in the literature [ 23 ].…”

“…In order to avoid dealing with explicit electrostatic interactions in DPD [ 30 ], we slightly increased the repulsion strength between the similarly charged head groups of DPPC ( = 110) to compensate for electrostatic repulsion [ 24 ]. The DPPC bilayer model was previously validated [ 24 ] by simulating a DPPC bilayer immersed in pure water and comparing the area per lipid molecule and the bilayer thickness against experiment and existing atomistic simulation results in the literature [ 23 ]. The DPD repulsion parameters ( ), as well as the parameters for bonded potentials, are reported in Table 1 .…”

“…Because phosphatidylcholines are the most important component of living organisms, we perform our simulations on a model membrane, dipalmitoylphosphatidylcholine (DPPC). DPPC is known as a useful model for understanding the physical properties of biological membranes [ 23 , 24 ]. We examine the effects of lipid concentration and surface curvature of CNTs on the structural evolution of lipid aggregates at the CNT interface and investigate the mechanism of self-assembly.…”