1 / 12

Original shell

Isostructure Replication. Replica. Original shell. Ha, et al. Te Infiltration. Degas framework 550  C with 10,000 psi pressure 50  C/hr to RT, release pressure Polish specific crystallographic orientation Etched silica using HF. PS/Air Networks. ~50 vol% Te. John Murry, AFRL

milla
Télécharger la présentation

Original shell

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Isostructure Replication Replica Original shell Ha, et al.

  2. Te Infiltration Degas framework 550 C with 10,000 psi pressure 50 C/hr to RT, release pressure Polish specific crystallographic orientation Etched silica using HF. PS/Air Networks ~50 vol% Te John Murry, AFRL Shane Juhl, AFRL Te/SiO2 network Ha, et al.

  3. Calculated & Measured Optical Properties Unpolarized Reflectance a ~ 10 mm X: 34-37 mm exoatmospheric VLWIR atmospheric windows Te:Air 50 vol% R X  M Joseph P. Constantino, AFRL

  4. BioHarvesting Natural Forms For Photonics Introduction: Photonic Band Gap Materials Bio-Templating Scaffolds and Top-Down Replication Bio-Colloids Self, Forced & Directed Assembly Summary

  5. 1 2 3 4 5 7 10 6 8 9 12 11 Virus Like Particles (foreign expression system) Virus Rod Icosahedra 20 faces 12 pentameric subunits Papillomavirus 20-300 nm PolioVirus Rotavirus

  6. Virus Characteristics Advantages Gained size (20-300 nm) shape (icosahedral, rod etc..) monodisperse cage-like structure (capsid), pH dependent gating of pores surface consists of well-defined proteins directional expression of attachment proteins non face-centered-cubic packing functionalinteriors triggered intake or release of core material facile modification of surface chemistries direct positional and orientational assembly Colloid Versus Virus Icosahedral Virus Capsid Spherical colloidal particle Heterogeneous, site specific surface chemistry Homogeneous surface chemistry Site specific surface charge determines lowest energy configuration of particles When they arrange (Viruses can have many orientations where spheres have only one)

  7. Chimeric Virus and Virus-Like Particle Materials Self-Assembly Cowpea Chlorotic Mottle Virus (CCMV) T. Douglas et al. Adv. Mat. (2002) 14: 415-418. Forced-Assembly M0 Directed-Assembly Viral Scaffold Monodisperse Heterogeneous, site specific surface chemistry Shape & Size M. Stone

  8. Iridoviruses (Insect Iridescent Viruses) Wiseana spp larvae uninfected infected Surface Fibrils (carbohydrate?) • Caspid • 1564 x major caspid protein • Arginine (R), Glutamate (E) surface residues (40, 260, 360) • (Emini Surf. Prop) • Substantial glycosylation sites (N X S(T)) • Core • Linear Genome 220kbp • (20kbp terminal redundant) • ~10 additional proteins • Phospholipid encap. (1-3 nm) Cell Section 140 nm V. Ward; T. Dokland

  9. Assembly Considerations Surface charge WIV PS Interaction Energy Weak Long Range Repulsion (relatively low surface charge) Short Range Repulsion from depletion (exclusion) forces from tethered chains Virus AND Substrate Juhl

  10. Dehydrated Pellet (no visual optical properties) 1 mm WIV Centrifugation 1. 5x washing 100 ml 20k rpm, 10kG decant 2. Glutaraldehyde crosslinked during last centrifugation 3. Store in di-H2O f~0.4 d~174 nm f~0.3 d~190 nm f~0.18 d~230 nm A A B C B C Reflectivity (% Ag Mirror) Normal Reflectance Ha, Chan, Juhl

  11. Assembly: Crystallization Cells Xie Cells. Flow cell Assembly Time: 4 days Dilute virus suspension Ordered Virus Mylar (cell wall) Virus Spacing and concentration (%) From Bragg equation A = 185 nm,(32%) B = 194 nm (28%) C = 207 nm (23%) D = 215 nm (20%) E = 225 nm (18%) Concentration dependence Juhl

  12. Thin region Thick region Transmission Angle (degree) f~0.23 d~210 nm Dehydrated Assembly Surface Region 40 Wavelength (nm) Wavelength (nm) 35 30 25 20 15 10 5 0 420 440 460 480 500 520 540 560 580 600 640 680 720 Assembly: Crystallization Cells High throughput screening of assembly parameters, large area for characterization, large grains 0.5 mm Juhl

More Related