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Virus templating for nanostructured devices

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ingrid spielman

on 30 April 2010

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Transcript of Virus templating for nanostructured devices

VIRUS TEMPLATING Quantum dot nanowires semiconductor materials Light-Harvesting Nanoantennae What is a Virus? How Can we use it? Why is it advantageous? Nanoring Assembly Conclusion How it works Tobacco Mosaic Virus
(TMV) cowpea chlorotic mottle virus
(CCMV) lithium ion Batteries Multilayered Materials Step 1: M13 viruses randomly deposited on LPEI/PAA multilayers Step 2: PAA has strong electrostatic interactions with LPEI
- competitive binding with virus
- this allows for separation and pushes M13 to surface Step 3: repulsive interactions of liquid-crystalline like M13 lead to spontaneous ordering process. - M13 (-)
- LPEI (+)
- PAA (-)

very thin LPEI/PAA multilayers (less than 10 nm) How does this interdiffusion and ordering process occur? monitored buildup process for series of polyelectrolytes atop
an already adsorbed viral stack. pH 5 Alternating depositions of LPEI and PAA a. superlinear thickness growth in an LPEI/PAA LBL
assembled film at pH 5.0.
solid line exponentially fit curve
error bars indicate standard deviations.
b. genetically engineered M13 virus and its functional groups to create biological or inorganic interaction sites
proteins at pIII in the head group
pVIII around the capsid body b, AFM image of the randomly stacked and aggregated M13 viruses on bilayers of strong PEM of polydiallylamine hydrochloride and polystyrene sulphonate.

c. AFM image of a closely packed monolayer of M13 virus on LPEI and PAA polyelectrolyte multilayer (PEM) Findings:
1. the originally adsorbed viral layer is highly disordered (Fig. 3a)
2. First M13 layer seem to diffuse to surface through LPEI (Fig. 3b)
3. counter-ionic PAA deposition buried under added PAA surface (Fig. 3c)
This process implies that LPEI plays a key role in driving the interdiffusion.
It appears that LPEI diffuses underneath the virus layer and into the multilayer matrix during

LPEI preferentially interacts with PAA over the M13 virus at pH5:
charge density of the capsid body of the M13 virus (1−1.5 e− per subunit)
charge density of LPEI (3−4 e− nm−1)30.

Test: replace LPEI with molecular weight ten times higher (250,000 Mw).
The reduced mobility of the larger-molecular-weight LPEI
blocking of chain interdiffusion by LPEI within the PEM,
virus cannot undergo a spontaneous ordering process
1.thin (> 5nm thick) base polyelectrolyte multilayer deposited on silicon
2. viruses directly adsorbed from a dilute buffer solution
3. LPEI and PAA were alternately adsorbed on top of the viral layer
4. topography of the thin film monitored systematically with increasing deposition number using tapping-mode atomic force microscopy (AFM) a. Zeta potential–pH dependence of the M13 virus

viruses were adsorbed at different pH values onto (LPEI/PAA):
b.Densely packed (pH 4.8, 60 viruses μm−2)
c. loosely packed (pH 5.15, 25 viruses μm−2) d. sparsely ordered (pH 5.5, 10 viruses μm−2) Density control in an electrostatically regulated viral monolayer stronger repulsive interactions at higher pH result in fewer adsorbed viruses. The mesophase ordering of the viruses at the top surface
is entropically driven and electrostatically regulated a. An assembled virus monolayer template for growing materials.

b. AFM/TEM images of gold nanoparticles attached to the virus monolayer.
5-nm cationic gold particles incubated on negatively charged M13 virus.
Particles align along the M13 virus.

c. AFM/TEM images of cobalt-nucleated virus nanowires.
The nucleation of cobalt increased contrast in the phase-mode AFM image.
AFM image: cobalt-coated virus is ~16 nm in width == ~ 2X virus width in a.

d. AFM and fluorescence images of the GaN virus nanowire films. Demonstration of templated biomineralization on the virus monolayer. Benefits of this system 1. electrostatic interactions for binding cationic nanoparticles to a negatively charged virus layer.

2. peptide mediated biomineralization ofmetal ions.

3. phage selected from a 100% display library for a peptide sequence on the viral coat that was specific to bind to GaN. Proven Uses 1. Simple modifications in the DNA sequence allow us to manipulate the intrinsic charge properties of the constituents, which yields an additional degree of tunability in this system.

2.the LBL adsorption process has been shown to be easily scalable up to metre length scales

3. With competitive binding the system is mobile and order can be created at a surface.
Most (PEM) systems maintain a strong ionically crosslinked network that does not allow for intermixing/diffusion of polyions: lead to irreversible and randomly placed viruses.

4.Easily tunable surface density via pH shift Polyelectrolyte multilayer (PEM) Assembly of System AFM image (left) and photograph (right, sample size 2 cm×4 cm). Nature 2006 Spontaneous assembly of viruses on
multilayered polymer surfaces PIL J. YOO, KI TAE NAM, JIFA Q, SOO-KWAN LEE, JUHYUN PARK, ANGELAM. BELCHER, PAULA T. HAMMOND filamentous phage viruses
helical rod shape composed of 2130 protein subunits
tubular shaped virus
300 nm long
18 nm wide,
4 nm wide interior cavity
cowpea chlorotic mottle virus (CCMV)
plant virus
protein capsid diameters of 26–28 nm
inner diameter of 20 nm that encapsulates nucleic acids

capsid forms a protein based cage-like structure
comprised of 180 identical protein subunits
modifiable both genetically and chemically
resembles ferritin (iron storage protein) found in bacteria M13 bacteriophage M13 VIRUS
Virus that infects bacteria

circular single-stranded DNA molecule
~6407 nucleotides long
encased in a flexible cylinder Cowpea Mosaic Virus cowpea mosaic virus (CPMV)

icosahedral virus
contains 60 copies of two protein subunits forming a protein cage
diameter of 30 nm
Tiny Easy to Genetically Modify versatile Phage display for surface peptide optimization Virii are useful for nanomaterial organization and templating.... 1. Gene insertion
2. Protein Display
3. Library Creation
4. Targeting Peptide
5. Binding and Isolation
6. Amplification Phage Display Routes for materials synthesis using viruses Rod-shaped Cage
structured Virus Display with Inorganic Materials Engineered M13 virus Displaying Peptides (a) The M13 virus evolved to grow materials on its pIII protein
major coat proteins of M13 (pVIII) and TMV have been used in the synthesis of crystalline nanowires.

(b) The viral cages of CCMV and CPMV, devoid of nucleic acids
used in the controlled synthesis of nanoparticles within its interior
external surface of the viral protein cage modified with polymers and fluorophores (c) Both M13 and TMV viruses have been used in the fabrication of liquid crystals.
incorporation of nanocrystals (blue) via nanocrystal nucleating viruses.
(d) Inorganically-modified liquid crystals fabricated into viral films and viral fibers for device tunability. (a) A combinatorial virus library made to expresses random peptide fusions
(b) Library exposed to a substrate s.a inorganic single crystal
positive binding interaction of the peptide fusion?
(c) wash with detergents to leave bound viruses,
isolate leftover via a disruption in binding conditions s.a pH change
amplify in bacterial host and reintroduced to fresh substrate surface.
repeated (b)/(c) 5x to mimicking evolutionary cycles
(d) DNA from the virus is isolated and sequenced to determine the identity of the peptide responsible for binding to the substrate. (b) NPs (spheres) localized on the viruses
potential of multiple materials engineering into one viral structure
length/shape customized depending on the genome size (a) M13 virus peptides fused to:
pIX shown in green
pVIII shown in orange
pIII shown in blue Body containing DNA surrounded by 2700 copies of the major coat protein, pVIII
repeating helical array
One end contains five copies of a minor coat protein, pIII.
Other end of the virus are five copies of another minor coat protein, pIX. 2003 PNAS Viral assembly of oriented quantum dot nanowires Chuanbin Mao, Christine E. Flynn, Andrew Hayhurst, Rozamond Sweeney, Jifa Qi, George Georgiou, Brent Iverson, and Angela M. Belcher Goal: Template Quantum Dot nanowires
How: Peptides selected by using a pIII phage display library for their ability to nucleate ZnS or CdS nanocrystals.
Results: nanowires 560 nm long and 20 nm wide Virus: 100-300nm
QD: 5 - 10nm Virus-Templated Assembly of Porphyrins into Light-Harvesting Nanoantennae JACS 2010 Yoon Sung Nam, Taeho Shin, Heechul Park, Andrew P. Magyar, Katherine Choi, Georg Fantner, Keith A. Nelson, and Angela M. Belcher Motivation:Sophisticated self-organization of the natural photosystems serves as a model for artificial photosynthetic systems that require efficient energy and electron transfers.

Goal: use M13 virus as templates guiding nanoscale organization of pigments via chemical linkage or electrostatic interactions

Results:molecular pigments can be
assembled into a light-harvesting antenna using M13 viruses as
templates through chemical linkage. Zn(II) deuteroporphyrin IX 2,4-bis(ethylene glycol) anti-streptavidin peptide (SWDPYSHLLQHPQ-), hexahistidine peptide (AHHHHHH-)
fused to the N-terminus of pIX
binds strongly to Ni(II)-nitrilotriacetic acid complex (Ni-NTA) Genetically Driven Assembly of
Nanorings Based on the M13 Virus Ki Tae Nam, Beau R. Peelle, Seung-Wuk Lee, and Angela M. Belcher Nano Letters 2003 Nanoring System Results Why a Ring? To form a ring, the two ends of the virus must meet and be held together via the linker molecule.
An increase of strain energy and some decrease in entropy would accompany this process.
Thermal fluctuation, mechanical forces induced by vortexing or hydrodynamic fluid motion including Brownian motion, may contribute to overcoming the required activation energy to bend the virus into a ring. Once formed, the ring structure is believed to be stable due to exceptionally strong binding between the displayed peptides and the linker. SCIENCE 2009 Fabricating Genetically Engineered High-Power Lithium-Ion Batteries Using Multiple Virus Genes Yun Jung Lee, Hyunjung Yi, Woo-Jae Kim, Kisuk Kang, Dong Soo Yun, Michael S. Strano, Gerbrand Ceder, Angela M. Belcher Idea: reduce material dimensions to boost Li+ ion and electron transfer in nanostructured electrodes. manipulating two genes:
peptide groups having affinity for single-walled carbon nanotubes (SWNTs) on one end
peptides capable of nucleating amorphous iron phosphate (a-FePO4) fused to the viral major coat protein

The virus clone with the greatest affinity toward SWNTs enabled power performance of a -FePO4 comparable to that of crystalline lithium iron phosphate (c-LiFePO4) and showed excellent capacity retention upon cycling
This environmentally benign low-temperature biological scaffold could facilitate fabrication
of electrodes from materials previously excluded because of extremely low electronic conductivity. Lithium Battery Anode: Graphite (LiC6), Hard Carbon (LiC6) Cathode: LiNiO2, LiFePO4 etc....
OR iron phosphate based materials: high power use Electrolyte: LiPF6, LiBF4, LiClO4 discharging- Li+ from anode to cathode
charging- Li+ from cathode to anode. Problem: M13 bacteriophage can be used for battery device fabrication synthesizing electrochemically active anode nanowires
organizing the virus on a polymer surface iron phosphate
lower toxicity
lower cost,
improved safety via high-power applications stability iron phosphate has kinetic limitations
fix by decreasing travel distance via NPs
How do we easily order the NPs? VIRUSES Solution: (A) TEMimages of templated a-FePO4 nanowires on E4 viruses.
(B) TGA curve of a-FePO4 nanowires synthesized on Ag NP–loaded E4. For comparison, a TGA curve of a-FePO4·H2O grown on E4 virus (without Ag NPs) is also presented.

(C and D) Electrochemical performance of a-FePO4 viral nanowires on E4 tested between 2.0 and 4.3 V. Active materials loading was 2.63 mg/cm2.
(C) First discharge curves at different rates.
(D) The Ragone plot representing rate performance in terms of specific power versus specific energy (only the active electrode mass is included in the weight). Characterization of a-FePO4 nanowire cathodes in a one-gene viral system E4 virus
modified M13 virus that has tetraglutamate (EEEE) fused to the N terminus of each copy of pVIII major coat protein extra carboxylic acid groups
exhibits increased ionic interactions with cations
template for materials growth thermal gravimetric analysis (TGA) determine changes in weight in relation to change in temperature to determine degradation and corrosion kinetics Ragon Plot characterising the trade-off between effective capacity and power handling Separate
(A) a-FePO4 nanowires templated on EC#2 viruses with no SWNT interaction
(B) SWNTs only

Attached SWNTs and templated Virus
(C) Low magnification (×10,000).
(D) Higher magnification (×30,000).
(E) High-resolution TEM (HRTEM)
images (×800,000). Morphology of the a-FePO4 grown on the
multifunctional viruses/SWNT hybrid nanostructures. TEM images EC#2 virus is a two-gene system virus with the strongest binding affinity to SWNTs. Biological toolkits: genetic engineering and biomolecular recognition (A) multifunctional M13 virus
The gene VIII protein (pVIII), a major capsid protein of the virus, is modified to serve as a template for a-FePO4 growth,
The gene III protein (pIII) is further engineered to have a binding affinity for SWNTs.

(B) Schematic of fabricating genetically engineered high-power lithium-ion battery cathodes using multifunctional viruses (two-gene system) biomolecular recognition and attachment to conducting SWNT networks make efficient electrical nanoscale wiring to the active nanomaterials, enabling high power performance. Battery used to power a green LED Virus: positive electrode
lithium metal foil: negative electrode Deposits form inside the electrolyte that inhibit lithium ion transport and the capacity of the cell diminishes.
Increase in internal resistance affects the cell's ability to deliver current. Good system but... Poor Cycle Life (A) First discharge curves at different rates.

(B) Ragone plot showing improvement in high-power performance with higher binding affinity toward SWNTs

Compare: Super P carbon or SWNTs.

(C) Capacity retention for 50 cycles at 1C rate. Electrochemical properties of the a-FePO4 viral nanowires in twogene systems Tested between 2.0 and 4.3 V
EC#2 virus is a two-gene system virus with the strongest binding affinity to SWNTs;
EC#1 is a two-gene system virus with moderate binding affinity;
E4 is a onegene system virus with no insert on pIII. Synthesis and organization of nanoscale II–VI semiconductor materials using evolved peptide specificity and viral capsid assembly The Journal of Materials Chemistry
2003 Christine E. Flynn, Chuanbin Mao, Andrew Hayhurst, Julie L. Williams, George Georgiou, Brent Iversona and Angela M. Belcher ZnS screening ZnS, CdS, CdSe, CdTe Semiconductor nanocrystal
Materials In nature, sulfur reducing bacteria biofilms form cubic ZnS from very dilute natural solutions Show that they can nucleate nanocrystals with a particular orientation Ingrid Spielman
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