We are investigating the integration of hybrid nanostructures as illustrated below using inorganic nanoparticles of spherical QDs (ZnS shell/CdSe core) with organic wild type and engineered mutant viral templates (icosahedral Cow Pea Mosaic Virus, CPMV). Extensive conjugation chemistry and constituent preparations and characterization were conducted on these initial hybrids, leading to discovery of a unique multi-stability effect. Such observations led to the application of QD-CPMV hybrids for non volatile memory as objective (1). Addressing solution based limitations of hybrid assembly and inhomogeneities led to formulation of objective (2), utilizing a substrate based method for integration of nanoparticle hybrids via self assembled monolayers (SAM). Extending development of substrate approach in objective (2), an unaggregated multifunctional nanoparticle hybrid CPMV-QD(1,2) system was demonstrated, using 2 different color emitting QDs on a mutant CPMV-T184C template (objective 3). Such a proof of concept documents advancement in multifunctional nanoparticle systems to combine more robust viral based architectures for future therapeutics development. Finally, investigation of insulating iron oxide (γ-Fe₂O ₃) nanoparticles suitable for bioimaging applications confirms universal applicability of modular substrate approach to nanoparticle hybrid integration in biological applications. (Abstract shortened by UMI.)