Preparation of nanoscaled bio-inorganic hybrid materials from tobacco mosaic virus

Functionalized bio/nano materials were prepared by using a tubular plant virus, Tobacco Mosaic Virus (TMV), as a template. Various noble metal clusters were deposited on the TMV template through the in situ mineralization of metal anions in an aqueous solution. Deposition of metal clusters was improved by using the genetically engineered TMV virion as template which has dense specific binding sites of cysteine residues on the outer surface. The cysteine residues worked as binding and nucleation sites in metal cluster deposition. The electrical conductance of TMV was increased after the metal cluster deposition, which suggests a potential use of metal/TMV composite nanomaterials as nanowires. Collidal stability diagrams of TMV virions in aqueous mixtures were obtained from dynamic light scattering experiments to find solvent conditions where the aggregation of TMV is prevented during the mineralization process. To further understand the colloidal stability of TMV suspensions, interaction energies between two cylindrical TMV particles were calculated numerically by the finite element method. The calculated interaction energy profiles agreed well with the aggregation behavior of TMV suspension, and provided a criterion where the TMV suspension can be kept stable without aggregation. Finally, maghemite nanoparticles were synthesized for application in post-conjugation with biomolecules. The capping molecules on the magnetic particles surface were modified to introduce functional groups that are reactive with biomolecules. Carboxyl groups were introduced by chemical reaction with shortened alkyl chains, which enhanced colloidal stability of the magnetic particles in ethanol