Selective binding of nanoparticles on surfaces and into polymeric matrices via directed hydrogen bonding interactions

The attachment of nanoparticles (NPs) onto planar surfaces and into specific phases of block copolymers is an important prerequisite for exerting their function on/in matrices for application in the field of nanotechnology. Besides non-directional binding modes (i.e. interfacial ordering effects) most known methods rely on intermolecular ordering forces to mediate binding of NPs onto surfaces. The approach towards NP-binding onto surfaces relies on directed, multiple hydrogen bonding systems. In this study the modular generation of surfaces and bulk-phases with hydrogen bonding receptors and the stable binding of the NPs onto the derivatized surfaces by atomic force microscopy (AFM) are reported. To this respect surfaces presenting Hamilton-type receptors (displaying association constants > 3 x 10(4) M-1) using Sharpless-1,3-dipolar cycloaddition reactions are prepared in high efficiency. Nanoparticle binding is studied with Au-NPs surface modified with barbituric acid-receptors. Binding of the particles to a surface presenting 100 mol% of receptor shows a highly dense packed layer of Au-NPs on the surface as seen by AFM measurements. The density of the receptors is the important factor in controlling a selective binding process, achieving > 100 fold binding selectivity. The present approach opens an efficient and general mode to direct nanoparticle assembly onto nanoscaled surfaces. Copyright (c) 2006 John Wiley & Sons, Ltd.