Inclusion Complex of α-Cyclodextrin with Poly(ethylene glycol) Brush

The inclusion complex (IC) of α-cyclodextrin (α-CD) with poly(ethylene glycol) (PEG) brush was investigated by neutron reflectometry and grazing-incidence wide-angle X-ray scattering. When the PEG brush was exposed to 10% aqueous α-CD solution, an IC consisting of randomly oriented α-CD polycrystals appeared. On the other hand, when the PEG brush was exposed to 5% aqueous α-CD solution, a uniform 10-nm-thick IC layer with α-CD stacked perpendicular to the substrate was formed. A 10-nm-thick IC was also found in the diluted PEG brush, even when exposed to the 10% α-CD solution. The characteristic 10-nm-thick layer is related to the folded crystalline structure of α-CD on the PEG brush.