Model of a magnetic polymersome containing a transportable substance

Purpose. Using a model of a magnetic polymersome, considering the substance located in the cavity, to study the features of the migration of particles of the transported substance depending on the permeability of the membrane and its magnetic properties using the method of coarse-grained molecular dynamics.
Methods. The polymersome under study is represented as a set of interacting particles of three types: polymer particles simulating the bilayer of an amphiphilic membrane; magnetic nanoparticles located in the membrane layer, and substance particles placed in the cavity. Polymer particles interact via elastic potentials that maintain equilibrium spherical vesicular geometry. Magnetic nanoparticles interact with each other as point dipoles. The steric interaction of magnetic particles with polymer walls is modeled as soft repulsion. The interaction of substance particles and polymer layers can be adjusted to account for their impermeability. Magnetic nanoparticles are considered impermeable for the substance carried by the polymersome. The model polymersome under study corresponds to a magnetopolymer particle with a diameter of about 100 nm located in an aqueous solution at 25°C, half of the cavity of which is filled by volume with substance particles. The behavior of the system is monitored over several realizations, followed by averaging using a numerical solution of the particle motion equations with introduced interactions and imposed conditions, and further analysis of the resulting sets of particles.
Results. In numerical experiments, the influence of the elastic properties of the membrane on the equilibrium state of a polymersome containing a given number of magnetic particles and particles of the transferred substance was investigated. The features of the migration of substance particles from the cavity of the polymersome were analyzed depending on the permeability of the membrane and the properties of magnetic nanoparticles located in the membrane layer.
Conclusion. The presented model allows us to describe the features of the release of particles of a substance enclosed in the cavity of a magnetic polymersome in the presence of a magnetoactive layer in the capsule membrane.

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