Lamellar and micellar phases of pluronic F127: insights from computer simulations

M. PICKHOLZ; WOOD, IRENE; J.M.R. ALBANO

Melbourne

Congreso; Emerging Polymer Technologies Summit (EPTS'16); 2016

EPTS

Motivation: Poloxamers, also known as Pluronics (PL), are linear triblockcopolymers. Flanked by hydrophilic blocks of poly(ethylene oxide), thecenter of the copolymer is made up of hydrophobic poly(propylene oxide).PL have been proposed as biomaterials for the design of drug deliverysystems. Aditionally, alteration of physicochemical properties of lipidbilayers by PL unimers could lead to enhance the passive transport ofsome drugs. In a previous work, we determined through simulations thestability of the interaction of PL F127 unimers with lipid bilayers[1]. Inparticular we found that u-shape (U) and straight (S) unimers were stablewithin the bilayer. The goal of this study is to evaluate the stability oflamellar and micellar phases of the copolymers, considering the unimerinternal structure (U or S).Methods: Molecular Dynamics (MD) simulations were carried out using aCoarse Grain (CG) F127 and water model. We investigate two kind ofstructures:-Lamellar phases: we compared the stability of monolayers (S) and bilayers(U) formed by this copolymers.-Micellar phases: we investigated the internal micelle structure of pre- andself- assembled micelle.Results and conclusions: Through this work we were able to shed light tothe molecular structre of the lamelar and micellar phases of PL F127 andcaputre important features that will improve our understaning of thispolymers as a drug delivery sistems. Evenmore, the size of micellarstructure found here were in good agreement with dynamic light scatteringmeasurements.References1. Wood,I.,Martini,M.F, Albano, J.M.R.,Cuestas M.L.,Mathet V.L.andPickholz M. Coarse grained study of pluronic F127: Comparisonwith shorter co-polymers in its interaction with lipid bilayers andself-agregation in water. Journal of Molecular Structure, 2016,1109, 106-133.