# US 2014/0194602 A1 · Metamaterial Optical Elements Self-Assembled on Protein Scaffolds > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0194602 A1 - Document ID: US20140194602A1 - Status: Published application - Kind: A1 - Application number: 14/207,807 - Filed: 2014-03-13 - Published: 2014-07-10 - Earliest claimed: 2012-01-12 - Assignees: The Government of the United States of America, as represented by the Secretary of the Navy - Inventors: Banahalli R. Ratna; Carissa M. Soto; Ronald W. Rendell; Jake Fontana; Jeffrey R. Deschamps - Web page: https://patentgrep.com/patent/US20140194602A1 ## CPC - C07K 14/005: from viruses - B82Y 20/00: Nanooptics, e.g. quantum optics or photonic crystals - G01N 21/554: {detecting the surface plasmon resonance of nanostructured metals, e.g. localised surface plasmon resonance} - H01B 1/02: mainly consisting of metals or alloys - H01B 1/12: organic substances {(organic macromolecular compounds or compositions C08)} - B82Y 30/00: Nanotechnology for materials or surface science, e.g. nanocomposites - B82Y 40/00: Manufacture or treatment of nanostructures - C07K: PEPTIDES (peptides in foodstuffs A23; obtaining protein compositions for foodstuffs, working-up proteins for foodstuffs A23J; preparations for medicinal purposes A61K; peptides containing beta-lactam rings C07D; cyclic dipeptides not having in their molecule any other peptide link than those which form their ring, e.g. piperazine-2,5-diones, C07D; ergot alkaloids of the cyclic peptide type C07D519/02; macromolecular compounds having statistically distributed amino acid units in their molecules, i.e. when the preparation does not provide for a specific; but for a random sequence of the amino acid units, homopolyamides and block copolyamides derived from amino acids C08G69/00; macromolecular products derived from proteins C08H1/00; preparation of glue or gelatine C09H; single cell proteins, enzymes C12N; genetic engineering processes for obtaining peptides C12N15/00; compositions for measuring or testing processes involving enzymes C12Q; investigation or analysis of biological material G01N33/00) - B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - H01B: CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES (selection for magnetic properties H01F1/00; waveguides H01P {; printed circuits H05K}) ## Abstract A genetically modified cowpea mosaic virus (CPMV) protein capsid serves as a scaffold for metal nanoparticles, preferably gold nanospheres, of 15 nm to 35 nm, creating plasmonic nanoclusters. The self-assembled nanoclusters gave rise to a 10-fold surface-averaged enhancement of the local electromagnetic field. Other viral capsids or virus-like proteins may also serve as such scaffolds. ## Claims ### Claim 1 A nanocluster comprising: a cowpea mosaic virus (CPMV) protein capsid, the protein genetically modified to incorporate a plurality of cysteine residues providing thiol groups on an exterior surface of the capsid, and a plurality of metal nanoparticles with a size between 15 nm and 35 nm bound to the thiol groups. ### Claim 2 (depends on 1) The nanocluster of claim 1, wherein twelve clusters of thiol groups are present on said exterior surface of said capsid. ### Claim 3 (depends on 1) The nanocluster of claim 1, wherein said protein comprises SEQ ID No: 7. ### Claim 4 (depends on 1) The nanocluster of claim 1, wherein said metal nanoparticles comprise gold nanoparticles and/or silver nanoparticles. ### Claim 5 (depends on 1) The nanocluster of claim 1, where said metal nanoparticles are gold nanospheres all of approximately the same size. ### Claim 6 (depends on 5) The nanocluster of claim 5, wherein said gold nanospheres have a size between 17 nm and 35 nm. ### Claim 7 A method of preparing nanoclusters, the method comprising: providing metal nanoparticles with a size between 15 nm and 35 nm, and contacting a viral protein capsid with the metal nanoparticles in a solution comprising a chelator, thereby obtaining nanoclusters comprising the metal nanoparticles bound to the viral protein capsid. ### Claim 8 (depends on 7) The method of claim 7, wherein said chelator is EDTA. ### Claim 9 (depends on 7) The method of claim 7, wherein said metal nanoparticles are in a state of being concentrated after their initial preparation. ### Claim 10 (depends on 7) The method of claim 7, wherein said contacting occurs with said metal nanoparticles are present in twenty fold molar excess relative to metal binding sites on said viral protein capsid. ### Claim 11 (depends on 7) The method of claim 7, wherein said metal nanoparticles comprise gold nanoparticles and/or silver nanoparticles. ### Claim 12 (depends on 7) The method of claim 7, where said metal nanoparticles are gold nanospheres all of approximately the same size. ### Claim 13 (depends on 12) The method of claim 12, wherein said gold nanospheres have a size between 17 nm and 35 nm. ### Claim 14 (depends on 7) The method of claim 7, wherein said metal nanoparticles are gold nanoparticles aged for at least one week after preparation thereof prior to reaction with said protein capsid. ### Claim 15 (depends on 7) The method of claim 7, wherein said viral protein capsid is in a state of being genetically engineered and/or chemically modified to incorporate metal binding sites on an exterior surface of the capsid. ### Claim 16 (depends on 7) The method of claim 7, wherein said viral protein capsid is that of cowpea mosaic virus (CPMV) in a state of being genetically engineered to incorporate a plurality of cysteine residues providing thiol groups on an exterior surface of the capsid ### Claim 17 (depends on 16) The method of claim 16, wherein twelve clusters of thiol groups are present on said exterior surface of said capsid. ### Claim 18 (depends on 17) The method of claim 17, wherein said protein comprises SEQ ID No: 7. ### Claim 19 A nanocluster comprising: a viral protein capsid and a plurality of metal nanoparticles with a size between of 15 nm to 35 nm bound to the thiol groups. ### Claim 20 (depends on 19) The nanocluster of claim 19, wherein said viral protein capsid is in a state of being genetically engineered to incorporate additional cysteine residues.