title: Role of surface charge density in nanoparticle-templated assembly of bromovirus protein cages.
abstract: Self-assembling icosahedral protein cages have potentially useful physical and chemical characteristics for a variety of nanotechnology applications, ranging from therapeutic or diagnostic vectors to building blocks for hierarchical materials. For application-specific functional control of protein cage assemblies, a deeper understanding of the interaction between the protein cage and its payload is necessary. Protein-cage encapsulated nanoparticles, with their well-defined surface chemistry, allow for systematic control over key parameters of encapsulation such as the surface charge, hydrophobicity, and size. Independent control over these variables allows experimental testing of different assembly mechanism models. Previous studies done with Brome mosaic virus capsids and negatively charged gold nanoparticles indicated that the result of the self-assembly process depends on the diameter of the particle. However, in these experiments, the surface-ligand density was maintained at saturation levels, while the total charge and the radius of curvature remained coupled variables, making the interpretation of the observed dependence on the core size difficult. The current work furnishes evidence of a critical surface charge density for assembly through an analysis aimed at decoupling the surface charge and the core size.
authors.affiliation: Department of Chemistry, Indiana University, Bloomington, Indiana 47405, USA.
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Daniel
authors.forename: Irina B
authors.initials: IB
authors.lastname: Tsvetkova
authors.forename: Zachary T
authors.initials: ZT
authors.lastname: Quinkert
authors.forename: Ayaluru
authors.initials: A
authors.lastname: Murali
authors.forename: Mrinmoy
authors.initials: M
authors.lastname: De
authors.forename: Vincent M
authors.initials: VM
authors.lastname: Rotello
authors.forename: C Cheng
authors.initials: CC
authors.lastname: Kao
authors.forename: Bogdan
authors.initials: B
authors.lastname: Dragnea
mesh_terms: D017795:Bromovirus; D004583:Electrons; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D010316:Particle Size; D013499:Surface Properties; D014764:Viral Proteins / Q000737:chemistry*
chemical_list: D014764:Viral Proteins; D006046:Gold