Self-Assembly of Phosphocholine Derivatives Using the ELBA Coarse-Grained Model: Micelles, Bicelles, and Reverse Micelles

Author(s)

de Souza, R. M. ^{[1, 2, 3]} ; Ratochinski, R. H. ^[1] ; Karttunen, Mikko ^{[4, 2, 3]} ; Dias, L. G. ^[1]

Affiliation

^[1] Univ Sao Paulo, Dept Quim, FFCLRP, Ave Bandeirantes 3900, BR-14040901 Ribeirao Preto, SP - Brazil

^[2] Univ Western Ontario, Dept Chem, London, ON N6A 3K7 - Canada

^[3] Univ Western Ontario, Ctr Adv Mat & Biomat Res, London, ON N6K 3K7 - Canada

^[4] Univ Western Ontario, Dept Appl Math, London, ON N6A 5B7 - Canada

• Document type: Journal article
• Source: JOURNAL OF CHEMICAL INFORMATION AND MODELING; v. 60, n. 2, p. 522-536, FEB 2020.
• Web of Science Citations: 1

Abstract

The ELBA coarse-grained force field was originally developed for lipids, and its water model is described as a single-site Lennard-Jones particle with electrostatics modeled by an embedded point-dipole, while other molecules in this force field have a three (or four)-to-one mapping scheme. Here, ELBA was applied to investigate the self-assembly processes of dodecyl-phosphocholine (DPC) micelle, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine/1,2-dihexaoyl-sn-glycero-3-p hosphocholine (DPPC/DHPC) bicelles, and DPPC/cyclohexane/water reverse micelles through coarse-grained molecular dynamics (MD) simulations. New parameters were obtained using a simplex algorithm-based calibration procedure to determine the Lennard-Jones parameters for cyclohexane, dodecane, and cyclohexane dodecane cross-interactions. Density, self-diffusion coefficient, surface tension, and mixture excess volume were found to be in fair agreement with experimental data. These new parameters were used in the simulations, and the obtained structures were analyzed for shape, size, volume, and surface area. Except for the shape of DPC micelles, all other properties match well with available experimental data and all-atom simulations. Remarkably, in agreement with experiments the rodlike shape of the DPPC reverse micelle is well described by ELBA, while all-atom data in the literature predicts a disclike shape. To further check the consistency of the force field in reproducing the correct shapes of reverse micelles, additional simulations were performed doubling the system size. Two distinct reverse micelles were obtained both presenting the rodlike shape and correct aggregation number. (AU)

• FAPESP's process: 17/03204-7 - Development and application of coarse-graining force field in self-assembled systems
• Grantee: Luis Gustavo Dias
• Support Opportunities: Regular Research Grants
• FAPESP's process: 13/08166-5 - Interfacial chemistry: drugs, peptides and ezymes interactions with membrane models
• Grantee: Iolanda Midea Cuccovia
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 18/13867-6 - Computational simulation of the electrolytic medium of secondary alkaline and/or alkaline earth metal ion batteries
• Grantee: Rafael Maglia de Souza
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate