Protein adsorption properties of OEG monolayers and dense PNIPAM brushes probed by neutron reflectivity

作者：Brouette N^*; Xue C; Haertlein M; Moulin M; Fragneto G; Leckband D E; Halperin A; Sferrazza M

来源：The European Physical Journal - Special Topics, 2012, 213(1): 343-353.

DOI：10.1140/epjst/e2012-01681-4

The structure of dense poly(N-isopropylacrylamide) (PNIPAM) brushes and oligo(ethylene glycol) (OEG) monolayers has been probed using neutron reflectometry and ellipsometry. The PNIPAM brush is swollen below the Lower Critical Solution Temperature (LCST) of 32 degrees C and is collapsed at 37 degrees C. Neutron reflectivity shows that below the LCST, the brush is described by a two-layer model: an inner dense layer and a hydrated outer layer. Above the LCST the collapsed brush forms a homogenous layer. With a fully deuterated myoglobin protein to increase the neutron scattering length density contrast, the reflectivity data show no detectable primary adsorption on the grafted OEG surface. A bound on the ternary adsorption onto PNIPAM chains forming dense brushes below and above the LCST is obtained.

• 出版日期2012-11