Directed self-assembly of CdS quantum dots on bacteriophage P22 coat protein templates.

The hierarchical organization of inorganic nanostructures has potential applications in diverse areas such as photocatalytic systems, composites, drug delivery and biomedicine. An attractive approach for this purpose is the use of biological organisms as templates since they often possess highly ordered arrays of protein molecules that can be genetically engineered for specific binding. Indeed, recent studies have shown that viruses can be used as versatile templates for the assembly of a variety of nanostructured materials because of their unique structural and chemical diversity. These highly ordered protein templates can be employed or adapted for specific binding interactions. Herein we report the directed self-assembly of independently synthesized 5 nm CdS nanocrystal quantum dots on ∼60 nm procapsid shells derived from wild-type P22 bacteriophage. The bacteriophage P22 shell is comprised of hexameric and pentameric clusters of subunits known as capsomeres. The pre-synthesized CdS QDs show the corresponding hexameric and pentameric patterns of assembly on these P22 shells, possibly by interacting with particular protein pockets.