title: A virus-based nanoplasmonic structure as a surface-enhanced Raman biosensor.
abstract: Fabrication of nanoscale structures with localized surface plasmons allows for substantial increase in sensitivity of chem/bio sensors. The main challenge for realizing complex nanoplasmonic structures in solution is the high level of precision required at the nanoscale to position metal nanoparticles in 3D. In this study, we report a virus-like particle (VLP) for building a 3D plasmonic nanostructure in solution in which gold nanoparticles are precisely positioned on the VLP by directed self-assembly techniques. These structures allow for concentration of electromagnetic fields in the desired locations between the gold nanoparticles or "hot spots". We measure the efficiency of the optical field spatial concentration for the first time, which results in a ten-fold enhancement of the capsid Raman peaks. Our experimental results agree with our 3D finite element simulations. Furthermore, we demonstrate as a proof-of-principle that the plasmonic nanostructures can be utilized in DNA detection down to 0.25 ng/μl (lowest concentration tested), while the protein peaks from the interior of the nanoplasmonic structures, potentially, can serve as an internal tracer for the biosensors.
authors.affiliation: Center for Bio/Molecular Science and Engineering, US Naval Research Laboratory, 4555 Overlook Avenue SW, Code 6900, Washington DC 20375, USA; Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom.
authors.forename: Nikolai
authors.initials: N
authors.lastname: Lebedev
authors.affiliation: Department of Mathematical Sciences and Computational Material Science Center, George Mason University, 4400 University Drive, Fairfax, VA 22030, USA; Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom.
authors.forename: Igor
authors.initials: I
authors.lastname: Griva
authors.affiliation: Center for Bio/Molecular Science and Engineering, US Naval Research Laboratory, 4555 Overlook Avenue SW, Code 6900, Washington DC 20375, USA; Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom.
authors.forename: Walter J
authors.initials: WJ
authors.lastname: Dressick
authors.affiliation: Department of Molecular Biology,The Scripps Research Institute, 10550, North Torrey Pines Road, La Jolla, California 92037, USA; Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom.
authors.forename: Jamie
authors.initials: J
authors.lastname: Phelps
authors.affiliation: Department of Molecular Biology,The Scripps Research Institute, 10550, North Torrey Pines Road, La Jolla, California 92037, USA; Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom.
authors.forename: John E
authors.initials: JE
authors.lastname: Johnson
authors.affiliation: Center for Bio/Molecular Science and Engineering, US Naval Research Laboratory, 4555 Overlook Avenue SW, Code 6900, Washington DC 20375, USA; Department of Mathematical Sciences and Computational Material Science Center, George Mason University, 4400 University Drive, Fairfax, VA 22030, USA; Department of Molecular Biology,The Scripps Research Institute, 10550, North Torrey Pines Road, La Jolla, California 92037, USA; Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom.
authors.forename: Yulia
authors.initials: Y
authors.lastname: Meshcheriakova
authors.affiliation: Center for Bio/Molecular Science and Engineering, US Naval Research Laboratory, 4555 Overlook Avenue SW, Code 6900, Washington DC 20375, USA; Department of Mathematical Sciences and Computational Material Science Center, George Mason University, 4400 University Drive, Fairfax, VA 22030, USA; Department of Molecular Biology,The Scripps Research Institute, 10550, North Torrey Pines Road, La Jolla, California 92037, USA; Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom.
authors.forename: George P
authors.initials: GP
authors.lastname: Lomonossoff
authors.affiliation: Center for Bio/Molecular Science and Engineering, US Naval Research Laboratory, 4555 Overlook Avenue SW, Code 6900, Washington DC 20375, USA; Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, United Kingdom. Electronic address: carissa.soto@nrl.navy.mil.
authors.forename: Carissa M
authors.initials: CM
authors.lastname: Soto
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation; D004247:DNA / Q000032:analysis* / Q000235:genetics*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006046:Gold / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000295:instrumentation; D066330:Printing, Three-Dimensional; D013059:Spectrum Analysis, Raman / Q000295:instrumentation*; D020349:Surface Plasmon Resonance / Q000295:instrumentation*; D014771:Virion / Q000648:ultrastructure*
chemical_list: D006046:Gold; D004247:DNA
keywords: Cowpea mosaic virus; Gold nanoparticles; Raman; SERS; Self-assembly; Virus-like particles