In:
Zeitschrift für Physikalische Chemie, Walter de Gruyter GmbH, Vol. 229, No. 7-8 ( 2015-8-28), p. 1119-1139
Kurzfassung:
Planar polyelectrolyte brushes are prepared by Langmuir–Schaefer
based grafting of perdeuterated (styrene) 49 -b-(acrylic
acid) 222 block copolymer (dPS-b-PAA) to dPS pre-coated silicon
supports with grafting density σ PAA from 0.07 to
0.11 nm – 2 . The structure of the solvent-swollen brushes,
i. e. the volume fraction profile of polymer segments, ϕ PAA , as a function of altitude z from the grafting
plane into the liquid phase is extracted from neutron reflectivity measurements. We find that for all cases investigated ϕ PAA ( z ) resembles a Gaussian profile. Although very
condensed, the PAA brushes can be loaded with bovine serum albumin (BSA). The integral amount of adsorbed BSA scales linearly with
grafting density. We compare our z -resolved volume fraction profile ϕ BSA ( z ) of BSA on PAA brushes with existing literature
on that system. It is found that a cross-over takes place in the adsorption scheme from ternary compressive, where proteins can
approach the grafting surface only by compressing the brus h, to
ternary insertive, where proteins enter the brush with only local perturbation of the concentration profile, as a function of R P / H max , where R P is the
Stokes-Radius of the protein, and H max is the
experimentally determined maximum height of the brush.
Materialart:
Online-Ressource
ISSN:
2196-7156
,
0942-9352
DOI:
10.1515/zpch-2014-0540
Sprache:
Englisch
Verlag:
Walter de Gruyter GmbH
Publikationsdatum:
2015
ZDB Id:
201103-7
