TY  - JOUR
A1  - Cherstvy, Andrey G.
T1  - Critical polyelectrolyte adsorption under confinement Planar slit, cylindrical pore, and spherical cavity
JF  - Biopolymers
N2  - We explore the properties of adsorption of flexible polyelectrolyte chains in confined spaces between the oppositely charged surfaces in three basic geometries. A method of approximate uniformly valid solutions for the Green function equation for the eigenfunctions of polymer density distributions is developed to rationalize the critical adsorption conditions. The same approach was implemented in our recent study for the inverse problem of polyelectrolyte adsorption onto a planar surface, and on the outer surface of rod-like and spherical obstacles. For the three adsorption geometries investigated, the theory yields simple scaling relations for the minimal surface charge density that triggers the chain adsorption, as a function of the Debye screening length and surface curvature. The encapsulation of polyelectrolytes is governed by interplay of the electrostatic attraction energy toward the adsorbing surface and entropic repulsion of the chain squeezed into a thin slit or small cavities. Under the conditions of surface-mediated confinement, substantially larger polymer linear charge densities are required to adsorb a polyelectrolyte inside a charged spherical cavity, relative to a cylindrical pore and to a planar slit (at the same interfacial surface charge density). Possible biological implications are discussed briefly in the end.
KW  - polymers
KW  - adsorption
KW  - electrostatics
KW  - confinement
Y1  - 2012
U6  - https://doi.org/10.1002/bip.22023
SN  - 0006-3525
VL  - 97
IS  - 5
SP  - 311
EP  - 317
PB  - Wiley-Blackwell
CY  - Hoboken
ER  -