Spatial distribution of polyelectrolyte and counterions in nanocapsules: a computer simulation study.
We study a spatial distribution of polyelectrolyte chains and counterions inside nanometer-size capsules by means of molecular dynamics simulation on the level of a colloidal model in which polyelectrolyte coils are modeled as soft charged spheres. The capsule shell is treated as a semipermeable membrane, impermeable for the polyelectrolyte chains, but allowing free diffusion of solvent molecules and counterions. As a result, counterions leak out from the capsule immersed into a fluid of low ionic strength. This counterion leakage leads to a formation of characteristic polyelectrolyte density profiles with the central plateau and large peaks at the wall. We show that a nonuniform distribution of the inner polyelectrolyte depends on the capsule radius, surface charge, concentration of encapsulated polyelectrolyte, and the volume fraction of capsules.
Stukan
Mikhail R
MR
Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany.
Lobaskin
Vladimir
V
Holm
Christian
C
Vinogradova
Olga I
OI
D000327:Adsorption; D040761:Biomimetic Materials / Q000737:chemistry*; D003198:Computer Simulation; D004058:Diffusion; D004573:Electrolytes / Q000737:chemistry*; D007477:Ions; D008956:Models, Chemical; D049329:Nanostructures / Q000737:chemistry*; D055672:Static Electricity
D004573:Electrolytes; D007477:Ions