The design of complex synthetic nanoscale materials that possess similarities in size and shape to several nanoscale biomolecules is receiving considerable attention, due to the expectation that they will exhibit (at least to some extent) similar properties and function.  This presentation will discuss amphiphilic core-shell nanospheres composed of a crosslinked network of hydrogel-like material surrounding a hydrophobic core environment.  A schematic representation of these spherical nanoparticles is illustrated below.  The basic components of the shell crosslinked knedel-like (SCK) nanoparticles resemble several biomolecular systems, including globular proteins, liposomes, and viruses.  The synthesis of these unique nanoparticles, characterization of their structure, composition and properties, and investigation of their biomimicry potential will be presented.

The approach to the preparation of such structures loosely models the basic construction tools found in nature, involving the use of hydrophobic interactions to assemble nanoscale structure, followed by covalent bond formation to stabilize that structure.  Therefore, the self-organization of di-block copolymers into polymer micelles within an aqueous solution is followed by intramicellar crosslinking selectively within the peripheral domain.  This approach ensures complete coverage of the core material with a uniform shell layer, while maintaining the desired nanoscale particle diameters and narrow size distributions.  Importantly, the surface, shell, interface, and core compositions and dimensions are controlled, to allow for modification of the properties within the different nanodomains.

Because the surface of the SCK nanoparticles experiences the initial contact with the surrounding environment, the nature of the surface is important for the SCK properties and their compatibility within their environment.  This is particularly important both in the solid state (e.g. as coatings or filler particles) and also in solution.  The transport of guests to and from the core of the SCK nanoparticles is dependent upon the shell thickness, crosslinking density and core fluidity.  Fluid-filled nanospheres and those with crystalline cores will also be described.  The final discussion will detail the transformation of these materials into hollow nanocages.