The research objective of this work is to develop methods of preparing multifunctional surface-grafted polymer assemblies that can operate as engines capable of directing motion of nanosized objects. The approach is to: 1) generate surface-grafted macromolecular assemblies with gradual variation of physico-chemical properties (grafting density, molecular weight) and surface-grafted "smart" polymers that undergo sharp and reversible transitions in response to temperature changes; 2) develop characterization tools for monitoring the transport on gradients; and 3) demonstrate motion of nanoparticles using the surface-tethered gradient assemblies and thermoresponsive polymers.
Understanding how "smart" polymer surfaces direct transportation of nanosized objects is expected to have a profound impact on basic science, technology, and life sciences. For example, uncovering the conditions under which such "smart" polymer surfaces act as molecular engines capable of controlling the motion of nanoparticles can be utilized in designing novel methods of material assembly or providing insight into partitioning of functional adsorbates on surfaces. In addition, the basic principles of nanoparticle motion can be used to understand protein adsorption and protein separation from multicomponent protein mixtures on artificial surfaces. The societal benefits resulting from this work include (but are not limited to) better design of medical drugs or capability of detecting bio-warfare agents.