Original shell

Replica

Isostructure Replication

Ha, et al.

PS/Air Networks

Te/SiO2 network

Te Infiltration

~50 vol% Te

Degas framework550 C with 10,000 psi pressure 50 C/hr to RT, release pressurePolish specific crystallographic orientationEtched silica using HF.

Ha, et al.

John Murry, AFRLShane Juhl, AFRL

Calculated & MeasuredOptical Properties

Te:Air 50 vol%

R

X

M

Unpolarized Reflectance

a ~ 10 mX: 34-37 m

Joseph P. Constantino, AFRL

atmosphericwindows

exoatmosphericVLWIR

Introduction: Photonic Band Gap Materials

Bio-TemplatingScaffolds and Top-Down Replication

Bio-ColloidsSelf, Forced & Directed Assembly

Summary

BioHarvesting Natural FormsFor Photonics

Papillomavirus

Rotavirus

PolioVirus

Virus

Virus Like Particles(foreign expression

system)

1

32

6

54

9

7

8

10

11 12

Rod

Icosahedra20 faces

12 pentameric subunits

20-300 nm

Icosahedral Virus Capsid

Heterogeneous, site specific surface chemistry

Homogeneous surface chemistry

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

functional interiors

triggered intake or release of core material

direct positional and orientational assembly

facile modification of surface chemistries

Virus Characteristics Advantages Gained

Spherical colloidal particle

Colloid Versus Virus

Site specific surface charge determines lowest energy configuration of particles When they arrange (Viruses can have many orientations where spheres have only one)

Chimeric Virus and Virus-Like Particle Materials

M. Stone

M0

T. Douglas et al. Adv. Mat. (2002) 14: 415-418.

Cowpea Chlorotic Mottle Virus (CCMV)

Viral ScaffoldMonodisperse

Heterogeneous, site specific surface chemistry

Shape & Size

Self-Assembly

Forced-Assembly

Directed-Assembly

V. Ward; T. Dokland

Cell Section

140 nm

SurfaceFibrils

(carbohydrate?)

Iridoviruses (Insect Iridescent Viruses)

Wiseana spp larvae

uninfected

infected

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)

Assembly Considerations

-70

-60

-50

-40

-30

-20

-10

0

0 0.2 0.4 0.6 0.8 1

Concentration LiCl (mM)

Zeta

Po

ten

tial (m

V)

Surface charge

Inte

rac

tio

n E

ne

rgy

PS

WIV

Virus AND SubstrateVirus AND SubstrateJuhl

Weak Long Range Repulsion (relatively low surface charge)

Short Range Repulsionfrom depletion (exclusion) forces from tethered chains

400 500 600 700 8000

10

20

30

40

50

60

Red: 780 - 622 nmOrange: 622 - 597 nmYellow: 597 - 577 nmGreen: 577 - 492 nmBlue: 492 - 455 nmViolet: 455 - 390 nm

Re

flect

ivity

(%

)

Wavelength (nm)

C

A

BCB

A

WIV Centrifugation

1. 5x washing100 l20k rpm, 10kGdecant

2. Glutaraldehyde crosslinked during last centrifugation

3. Store in di-H2O

Dehydrated Pellet(no visual optical

properties)

1 mNormal Reflectance

Ref

lect

ivit

y (%

Ag

Mir

ror)

Ha, Chan, Juhl

~0.4d~174 nm~0.3

d~190 nm

~0.18d~230 nm

Assembly: Crystallization Cells

Concentration dependence

Ordered Virus

Dilute virus suspension

Mylar (cell wall)

A = 185 nm,(32%)B = 194 nm (28%)

D = 215 nm (20%)

E = 225 nm (18%)

C = 207 nm (23%)

Virus Spacing and concentration (%)

From Bragg equation

Xie Cells. Flow cellAssembly Time: 4 days

Juhl

Assembly: Crystallization Cells

Thin region Thick region

High throughput screening of assembly parameters, large area for characterization, large grains

Dehydrated AssemblySurface Region

Juhl

Wavelength (nm)420 440 460 480 500 520 540 560 580 600 640 680 720

0

5

10

15

20

25

30

35

40

Wavelength (nm)

Angle (degree)

Transmission

~0.23d~210 nm

0.5 mm