FINAL BES Summaries - 2013-04-11x - ATL International, Inc.

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i

Contents

PREFACE

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III

INSTITUTIONS RECEIVI
NG GRANTS

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................................
................................
...

IV

DOE NATIONAL LABORAT
ORIES

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VI

I.

MATERIALS SCIENCES A
ND ENGINEERING DIVIS
ION

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....
I
-
1

Biomolecular Materials

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I
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1

Institutions Receiving Grants

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I
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1

DOE National Laboratories

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..
I
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47

Electron and Scanning Probe Microscopies

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I
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61

Institutions Receiving Grants

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...............................
I
-
61

DOE National
Laboratories

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................................

I
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105

Experimental Condensed Matter Physics

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I
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116

Institutions Receiving Grants

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.............................

I
-
116

DOE National Laboratories

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I
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184

Materials Chemistry
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I
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210

Institutions Receiving Grants

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I
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210

DOE National Laboratories

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I
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266

Mechanical Behavior and Radiation Effects

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I
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284

Institutions Receiving Grants

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I
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284

DOE National Laboratories

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I
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317

Neutron Scattering

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I
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327

Instit
utions Receiving Grants

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I
-
327

DOE National Laboratories

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I
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351

Physical Behavior of Materials

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.

I
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358

Institutions Receiving Grants

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I
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358

DOE National Laboratories

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I
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409

Synthesis and Processing Science
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.............................

I
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431

Institutions Receiving Grants

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I
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431

DOE National Laboratories

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................................

I
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477

Theoretical Condensed Matter Physics

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....................

I
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488

Institutions Receiving Grants

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I
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488

DOE National Laboratories

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................................

I
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567

X
-
ray Scattering

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......................

I
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585

Institut
ions Receiving Grants

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.............................

I
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585

DOE National Laboratories

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................................

I
-
609

ii

|

II.

CHEMICAL SCIENCES, G
EOSCIENCES, & BIOSCI
ENCES DIVISION

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...................
II
-
1

AMO Sciences

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..........................

II
-
1

Institutions R
eceiving Grants

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...............................

II
-
1

DOE National Laboratories

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................................
................................
.
II
-
47

Catalysis Science
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......................
II
-
54

Institutions Receiving Grants

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..............................
II
-
54

DOE National Laboratories

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...............................

II
-
163

Condensed Phase and Interfacial Molecular Science

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II
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182

Institutions Receiving Grants

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............................

II
-
182

DOE National Laboratories

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...............................

II
-
242

Gas
-
Phase Chemical Physics

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................................
...

II
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256

Institutions Receiving Grants

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............................

II
-
256

DOE National Laboratories

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...............................

II
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296

Geosciences

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..........................

II
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306

Institutions

Receiving Grants

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............................

II
-
306

DOE National Laboratories

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...............................

II
-
369

Heavy Element Chemistry

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......

II
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386

Institutions Receiving Grants

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............................

II
-
386

DOE National Laboratories

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...............................

II
-
405

Photosynthetic Systems

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II
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416

Institutions Receiving Grants

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II
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416

DOE National Laboratories

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...............................

II
-
470

Physical Biosciences
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...............

II
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477

Institutions Receiving Grants

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............................

II
-
477

DOE National Laboratories

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...............................

I
I
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529

Separations and Analysis
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II
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536

Institutions Receiving Grants

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II
-
536

DOE National Laboratories

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...............................

II
-
569

Solar Photochemistry
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II
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578

Institutions Receiving Grants

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II
-
578

DOE National Laboratories

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...............................

II
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633

III.

SCIENTIFIC USER FACI
LITIES DIVISION

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.......................
III
-
1

Institutions Receiving Grants

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..............................

III
-
1

DOE National Laboratories

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................................
.

III
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8

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iii

Preface

This is a collection of summaries for more than
1400

research projects funded by the Office of Basic
Energy Sciences (
BES
) in Fiscal Year
2012

at some 180 institutions across the U.S. This volume is
organized
along the three BES divisions: Materials Sciences and Engineering (
MSE
); Chemical Sciences,
Geosciences, and Biosciences (
CSGB
); and Scientific User Faci
lities (
SUF
). Within the MSE and CSGB
divisions, the summaries are further organized by research activity. For the SUF division, summaries are
provided for the research projects in accelerator physics and
x
-
ray and neutron detectors.

This is the
second annual

issue of BES research program summaries. The volume covers core research
activities supported by BES. While every attempt was made to obtain a summary for each research
project supported in FY 20
12
, t
here may be some omissions. Some specific activities are not covered,
including the construction and operation of
scientific user facilities
,
Energy Fron
tier Research Centers
,
Fuels from Sunlight
Energy Innovation Hub
, the Experimental Program to Stimulate Competitive
Research (
EPSCoR
), and the Small Business Innovation Research (
SBIR
)/Small Business Technology
Transfer (STTR) program. Each project summary includes: title, point of contact (to whom questions
should be address
ed), principal investigator, other senior investigators, postdoctoral fellows, graduate
students, approximate annual funding, and a brief description of the research project.

This collection is complementary to the
Basic Energy Sciences 2011 Summary Report
,

which describes in
detail how BES is structured and managed and provides overviews of each of the three BES divisions and
special research activities. The
Basic Energy Sciences
2011

Summary Report
identifies the cover images
and provides related research highlights.

iv

|

Institution
s

Receiving Grants
Akron, University of

Alabama, University of

Alfred University

Arizona State University

Arizona, University of

Arkansas, University of

Auburn University

Boise State University

Boston College, Trustees of

Boston University

Bowling Green State University

Boyce Thompson Institute

Brandeis University

Brigham Young Univers
ity

Brown University

California Institute of Technology

California State University
-
East Bay

California State University
-
Fullerton

California State University
-
North Ridge

California
-
Berkeley, University of

California
-
Davis, University of

California
-
Irvine,

University of

California
-
LA, University of

California
-
Riverside, University of

California
-
San Diego, University of

California
-
Santa Barbara, University of

California
-
Santa Cruz, University of

Carnegie Institution of Washington

Carnegie Mellon University

Case Western Reserve University

Central Florida, University of

Central Michigan University

Chicago, University of

Cincinnati, University of

City College of New York

Clark Atlanta University

Clarkson University

Clemson University

Colorado School of Mines

Co
lorado State University

Colorado, University of

Columbia University

Connecticut, University of

Cornell University

Dartmouth College

Delaware, University of

Drexel University

Duke University

Emory University

Florida International University

Florida State Un
iversity

Florida, University of

George Mason University

George Washington University

Georgetown University

Georgia State University

Georgia Tech Research Corp

Georgia, University of

Harvard University

Hawaii, University of

Houston, University of

Illinois,
University of

Indiana State University

Indiana University

Iowa State University

Iowa, University of

Johns Hopkins University

Kansas State University

Kansas, University of

Kent State University

Kentucky, University of

Lehigh University

Life Sciences Researc
h Foundation

Louisiana State University

Marine Biological Laboratory

Maryland, University of

Massachusetts Institute of Technology

Massachusetts, University of

Miami University

Miami, University of

Michigan State University

Michigan Technical University

Michigan, University of

Minnesota, University of

Mississippi State University

Missouri University of Science

Missouri, University of

Montana State University

National Academy of Sciences

National Aeronautics and Space Administration

National Institute of S
tandards and Technology

National Science Foundation

|
v

Nebraska, University of

Nevada, University of

New Jersey Institute of Technology

New Jersey
-
Rutgers, State University of

New Mexico State University

New Mexico, University of

New York University

New York,

State University Research Fund,
Purchase College

New York
-
Binghamton, State University of

New York
-
Buffalo, State University of

New York
-
City College, City University of

New York
-
Hunter College, City University of

New York
-
Lehman College, City University
of

New York
-
Queens College, City University of

New York
-
Stony Brook, State University of

New York
-
Syracuse, State University of

North Carolina Central University

North Carolina State University

North Carolina, University of

North Dakota State University

North Texas, University of

Northeastern University

Northern Illinois University

Northwestern University

Notre Dame, University of

Ohio State University

Ohio University

Oklahoma State University

Oklahoma, University of

Oregon State University

Oregon, Univer
sity of

Pennsylvania State University

Pennsylvania, University of

Pittsburgh, University of

Portland State University

Princeton University

Purdue University

Rensselaer Polytechnic Inst.

Rice University, William Marsh

Richmond, University of

Rochester, Univ
ersity of

Salk Institute for Biological Studies

San Diego State University

Scripps Research Institute

South Carolina, University of

South Florida, University of

Southern California, University of

Southern Illinois University

Stanford University

Stony Brook

University

Temple University

Tennessee, University of

Texas A&M University

Texas Tech University

Texas, University of

Texas, University of El Paso

Toronto, University of

Tufts University

Tulane University

U.S. Department of Agriculture

Utah State Universi
ty

Utah, University of

Vanderbilt University

Vermont, University of

Virginia Commonwealth University

Virginia Polytechnic Inst. And State U.

Virginia, University of

Washington State University

Washington University, St. Louis

Washington, University of

Wayn
e State University

West Virginia University

Western Michigan University

William and Mary, College of

Wisconsin
-
Madison, University of

Wisconsin
-
Milwaukee, University of

Woods Hole Oceanographic Institution

Wright State University

Wyoming, University of

Yale University


vi

|

DOE National Laboratories

Ames Laboratory

Argonne National Laboratory

Brookhaven National Laboratory

Jefferson Lab

Lawrence Berkeley National Laboratory

Lawrence Livermore National Laboratory

Los Alamos National Labor
atory

National Renewable Energy Laboratory

Oak Ridge National Laboratory

Pacific Northwest National Laboratory

Sandia National Laboratories
-
Albuquerque and Livermore

Savannah River National Laboratory

SLAC National Accelerator Laboratory



MSE Summaries|
I
-
1

I.

MATERI
ALS SCIENCES AND ENG
INEERING

DIVISION

Biomolecular Materials

Institutions Receiving Grants

Multicomponent Protein Cage Architectures for Photocatalysis

Institution:

Alabama, University of

Point of Contact:

Gupta, Arunava

Email:

agupta@mint.ua.edu

Principal

Investigator:

Gupta, Arunava

Sr. Investigator(s):

Prevelige, Peter, Alabama, University of

Students:

0 Postdoctoral Fellow(s), 2 Graduate(s), 0 Undergraduate(s)

Funding:

$220,000

PROGRAM SCOPE

The primary goal of the project is to develop protein
-
template
d approaches for the synthesis and
directed assembly of semiconductor nanomaterials and dyes that are efficient for visible light absorption
and hydrogen production.

In general, visible
-
light
-
driven photocatalysis reactions exhibit low quantum
efficiency f
or solar energy conversion primarily because of materials
-
related issues and limitations, such
as the control of the band gap, band structure, photochemical stability, and available reactive surface
area of the photocatalyst.
Synthesis of multicomponent hi
erarchical nano
-
architectures, consisting of
semiconductor nanoparticles (NPs) and coordination polymers with desired optical properties fabricated
to maximize spatial proximity for optimum electron and energy transfer, represents an attractive route
for a
ddressing the problem
.

Virus capsids are highly symmetrical, self
-
assembling protein cage nanoparticles that exist in a range of
sizes and symmetries. Selective deposition of organic or inorganic materials, by design, at specific
locations on virus capsid
s affords precise control over the size, spacing, and assembly of nanomaterials,
resulting in uniform and reproducible nano
-
architectures. We utilize the self
-
assembling capabilities of
the 420 subunit, 60 nm icosahedral, P22 virus capsid to direct the nuc
leation, growth, and proximity of a
range of component materials. Controlled fabrication on the exterior of the temperature stable shell is
achieved by genetically encoding specific binding peptides into an externally exposed loop which is
displayed on eac
h of the 420 coat protein subunits. Localization of complimentary materials to the
interior of the particle is achieved through the use of “scaffolding
-
fusion proteins. The scaffolding
domain drives coat protein polymerization resulting in a coat protein s
hell surrounding a core of
approximately 300 scaffolding/fusion molecules. The fusion domain comprises a peptide which
specifically binds the semi
-
conductor material of interest.

FY 2012 HIGHLIGHTS

We have built on our previous success in nucleating the formation of CdS and ZnS nanocrystals on the
exterior of P22 and demonstrated the feasibility of employing scaffolding
-
fusion proteins to nucleate
I
-
2

| MSE Summaries

internal nanocrystal formation. Fusion scaffolding pr
oteins were designed based on the observation that
an N
-
terminally deleted version of the 303 amino acid scaffolding protein spanning residues 141
-
303
was capable of promoting assembly both
in vivo

and
in vitro
. Using standard molecular biology
techniques,

coding sequences encoding short peptides reported to bind TiO
2
or CdS were introduced at
the N
-
terminus of the coding sequence of the 141
-
303 scaffolding protein deletion. Both the TiO
2

and
CdS, grown under

ambient conditions, are observed to be crystalli
ne. More significantly, preliminary
results indicate that the rutile rather than the anatase phase is crystallized for TiO
2
, which generally
requires high temperatures (> 500°C) to produce using traditional synthesis methods.

Engineering the Interface Betw
een Inorganic Materials and Cells

Institution:

California
-
Berkeley, University of

Point of Contact:

Schaffer, David

Email:

schaffer@berkeley.edu

Principal Investigator:

Schaffer, David

Sr. Investigator(s):


Students:

0 Postdoctoral Fellow(s), 3 Graduate(s)
, 0 Undergraduate(s)

Funding:

$185,000

PROGRAM SCOPE

Cells perform numerous functions
,

including energy capture, storage, and transduction and the
conversion of chemical to mechanical energy during transport.

Any adaption of cells and these
fundamental pro
cesses to DOE goals

(e.g.,

environmental bioremediation, energy harvesting, energy
transduction, and biosensing
)
will require them to function outside of their native environment, as
components of hybrid cell
-
material systems.

Since most interfaces with in
organic materials are
inherently unnatural, the goal of this work will be to provide the fundamental underpinnings for such
systems by developing novel and broadly applicable approaches to engineer both the materials and the
cells in order to achieve effec
tive integration.

In particular, the proposed work will focus on engineering
the interface between inorganic materials

(
gold and silica
)

and three model cell types
(
neural stem cells,
fibroblasts, and neutrophils
)
.

We will investigate and optimize a range
of cellular behaviors and
functions, including adhesion, proliferation, migration, and chemotaxis (the latter two constituting
behaviors that fundamentally involve the conversion of chemical energy into mechanical energy).

Both
sides of the interface will
be controlled through a parallel and integrated effort to engineer the material
and the cells to analyze and regulate cell function.

Our work will provide fundamental insight into the
interactions of cells with tethered peptides and proteins.

We will also
explore a variety of cellular
engineering efforts to promote cell adhesion, proliferation, migration, and chemotaxis on “pristine”
inorganic materials.

The ability to promote cell robustness, viability, and function on inorganic materials
will be critical
for designing the hybrid cell
-
materials systems of the future.

FY 2012 HIGHLIGHTS

As discussed in our original proposal,
optimiz
ing

cell function in hybrid “living materials
” would greatly
benefit from novel approaches

to render cells responsive to novel “
orthogonal” cues.

Our approach
makes use of the photoreactive PHR domain from the cryptochrome 2

(CRY2)

protein
. I
t
was

shown
in
one report that CRY2
can
,

under some circumstances
,

homo
-
oligomerize in response to light in its host
plant
organism,
Arabidopsis
.

A number of cellular signal transduction events involve protein
oligomerization.

We anticipated that fusion of CRY2 to
several proteins whose oligomerization has
implicated in the activation of key signaling pathways may enable light
-
mediated
control over these
MSE Summaries|
I
-
3

signaling pathways, and downstream cellular behavior. For example,
exposure of
cells expressing the
CRY2
-
mCherry

fused to the receptor protein LRP6

to blue light induced the oligomerization of the
protein

and the downstream activation of

the canonical Wnt pathway. In addition, we have engineered
this system to enable light
-
control over signaling by Rho GTPases
.

These results are currently under
review for publication. In addition, these

capabilit
ies are

now being explored to determine whe
ther the
technology can serve as a general platform to modulate protein assembly and structure inside cells and
activate numerous signaling activities in a light
-
responsive manner, including pathways that can mediate
cell adhesion t
o inorganic material sur
faces.

Dynamic Self
-
Assembly: Structure,
Dynamics,and Function Relations i
n Lipid Membranes

Institution:

California
-
Davis, University of

Point of Contact:

Parikh, Atul

Email:

anparikh@ucdavis.edu

Principal Investigator:

Parikh, Atul

Sr. Investigator(s):

Sinha, Sunil, California
-
San Diego, University of

Students:

1 Postdoctoral Fellow(s), 3 Graduate(s), 2 Undergraduate(s)

Funding:

$327,000

PROGRAM SCOPE

We have two over
-
arching objectives for the proposed work. First, we seek to abstract a

physical
science
-
based understanding of fundamental rules that determine dynamic self
-
assembly

processes in
lipid bilayer membranes
-

a versatile class of biologically inspired interfacial complex fluids.

Second, our
longer
-
term objective is to translate these physical pr
inciples into quantitative design rules

for the

development of new classes of

materials that exhibit complex, cooperative,

and adaptive behavior. Our
approach is primarily experimental. We employ assemblies of

lipid mixtures (e.g., supported lipid
bilayers
, vesicles, and lipid multilamellae) exhibiting
pre
-
determined
physical
-
chemical properties (e.g.,
chemical composition, transition temperatures, and

curvatures) and examine their spontaneous
mesoscopic organization and dynamic

remodeling in response to ex
ternal perturbations. We study the
organization of mixed lipid

bilayers in
the
presence of constraints including spatial compartmentalization
and asymmetry (structural and

chemical) across the bilayer leaflets. The dynamic remodeling is
examined under extr
aneously imposed

physical
-
chemical conditions including (1) interfacial hydration
gradients
,
(2) imposed curvatures
,

and

(3
) lipid
-
specific chemistries.
These

dynamic

structural

reorganizations
are characterized
using spatially
-

and temporally
-
resolved mic
roscopy and spectroscopy
(wide
-
area and total internal reflection based

fluorescence, ellipsometric, vibrational
)
techniques
. Sunil
Sinha at UC San Diego collaborates with us in all experiments and contributes structure characterization
using a combination

of

x
-
ray reflectivity, x
-
ray photon correlation spectroscopy,
and neutron reflectivity
measurements
.

FY 2012 HIGHLIGHTS

Substantial progress, detailed in many archival publications, was made during the Fiscal Year 2012
toward each of the objectives, one of which is highlighted below.
W
e
have
found that in membrane
multilayers, prepared from laterally phase
-
separating lipid mixtures, a remarkable columnar order
emerges from the coupling of two
-
dimensional intralayer phase

separation and interlayer smectic
ordering.
This

coupling propagates across hundreds of membrane lamellae, producing long
-
range
alignment of phase
-
separated domains. Quantitative analysis of real
-
time dynamical experiments
reveals that there is an interpl
ay between intralayer domain growth and interlayer coupling, suggesting
I
-
4

| MSE Summaries

the existence of cooperative multilayer epitaxy.

We postulate that such long
-
range epitaxy is solvent
-
assisted, and that it originates from the surface tension associated with differen
ces in the network of
hydrogen
-
bonded water molecules at the hydrated interfaces between the domains and the
surrounding phase. Our findings might inspire the development of self
-
assembly
-
based strategies for the
long
-
range alignment of functional lipid do
mains.

This work is accepted for publication in Nature
Materials, Dec. 2012 issue and will be highlighted by a cartoon on the Front Cover of the issue.

Bioinspired Hydrogen Bon
ding
-
Mediated Assembly of Nano
-
O
bjects toward Adaptive and Dynamic
Materials

In
stitution:

California
-
Irvine, University of

Point of Contact:

Guan, Zhibin

Email:

zguan@uci.edu

Principal Investigator:

Guan, Zhibin

Sr. Investigator(s):


Students:

0 Postdoctoral Fellow(s), 2 Graduate(s), 1 Undergraduate(s)

Funding:

$154,000

PROGRAM SCOPE

Nature has evolved many complex, multicomponent materials having adaptive and responsive
properties for energy efficiency purposes. For manmade materials, it is highly desirable to harness such
dynamic properties for energy efficient applications.

Inspire
d by Nature, this proposal details our plan of
dev
eloping H
-
bonding
-
mediated self
-
assembly of nano
-
materials having adaptive and dynamic
properties for energy relevant applications. The approach we propose here is to use strong, reversible
H
-
bonding mediat
ors to achieve
dynamic nano assemblies. A serie
s of quadruple H
-
bonding mediators,
both for self
-
complementary and orthogonal, will be synthesized, which are subsequently attached to
various nano
-
objects including carbon
-
based (C60 & CNTs), metallic (GNPs)
, and inorganic nanoparticles
(SNPs). The functionalized NPs will be dynamically assembled both into 1
-
D polymer chains and 3
-
D
networks. H
-
bonding mediated dynamic assembly of those functionalized nano
-
objects will be carefully
investigated in solution, f
ilm, and macroscopic solid state. We will systematically tune a number of
structural and experimental parameters, including the type and size of nano
-
objects, the category and
density of H
-
bonding mediators, the length and flexibility of the linker connect
ing the H
-
bonding units to
the nano cores, and the processing condition for inducing the nano assembly (e.g., solvent,
temperature, and time).
The
adaptive and dynamic properties
, including self
-
healing capability, will be
systematically investigated
. Buil
ding upon suc
c
esses from this proposed study, in future studies a similar
concept can be applied to various other nano systems for the dynamic assembly of complex,
multicomponent nano systems having truly multi
-
functional and environmentally adaptive, self
-
healing
materials.

FY 2012 HIGHLIGHTS

In this year, we have achieved two major breakthroughs in designing dynamic/self
-
healing polymeric
materials. (1) We succeeded
in
a new design of

strong polymeric material able to spontaneously repair
itself, without
any external help from light, heat, healing agents, or plastizers/solvents. The key to the
success is the hard/soft multiphase nanophase morphology which combines the advanced mechanical
properties of nanocomposites with the dynamic self
-
healing features o
f supramolecular assembly.

This
work was published in
Nature Chemistry

and highlighted
by
Chemical & Engineering News
,
http://cen.acs.org/articles/90/i14/Polymer
-
Heal
-
Thyself.html
. (2) We demonstrated the first example of
MSE Summaries|
I
-
5

self
-
healing polymer using olefin metathesis via dynamic covalent bond exchange. In bulk the material
also exhibits unusual malleability due to dynamic C=C double bond exchange. The work was published in
the
Journ
al of American Chemical Society

and highlighted
by
Chemical & Engineering News
,
http://cen.acs.org/articles/90/i33/Polymer
-
Healing
-
Olefin
-
Metathesis.html
.

Bio
-
Inspir
ed Routes for Synthesizing Efficient Nanoscale Platinum Electrocatalysts

Institution:

California
-
San Diego, University of

Point of Contact:

Cha, Jennifer

Email:

Jennifer.Cha@colorado.edu

Principal Investigator:

Cha, Jennifer

Sr. Investigator(s):

Wang,
Joseph, California
-
San Diego, University of

Students:

2 Postdoctoral Fellow(s), 1 Graduate(s), 0 Undergraduate(s)

Funding:

$230,000

PROGRAM SCOPE

The proposed research will focus on the controlled bottom
-
up biochemical synthesis of highly efficient
electro
catalytic platinum nanocrystals through a rational biochemical design.
By tuning the biochemical
input
,

we expect to tailor the size, shape, and crystal orientation of the resulting platinum nanocrystals,
and hence to maximize their electrochemical reactivity.
We will employ specially
-
designed peptides to
promote and control the growth and morphology of pla
tinum nanocrystals through binding to specific
crystal planes of platinum. We will also study the use of macromolecular scaffolds as templates to probe
novel bio
-
inorganic interfaces for catalysis, including oxygen reduction reaction. In addition, novel
mi
croporous electrode materials and nanoparticle supports will be engineered and studied for
enhanced fuel cell performance. Through these studies, we will be able to critically evaluate the
electrocatalytic activity of bio
-
conjugated Pt nanostructures as an

e
ffect of crystal size, morphology,
peptide and polymer orientation and loading on the nanoparticles and the specific bio
-
inorganic
interface.

FY 2012 HIGHLIGHTS

Major accomplishments during the second year include
(
1)

synthesis of amino acid functionali
zed
polyethylene glycol (PEG) polymers to investigate the role of each amino acid for platinum binding,
nanoparticle synthesis, and catalysis;
(
2)

synthesis of defined platinum nanoparticles from the amino
acid PEG polymers; and
(
3)

development of novel mi
croporous electrode materials and nanoparticle
supports for enhanced fuel performance. In the past year, we completed studies analyzing the use of
simple short linear chains of polyethylene glycol to synthesize well
-
defined sub
-
10 platinum
nanoparticles, i
ncluding cubes and truncated cubes. We furthermore determined that the platinum
nanoparticle growth was controlled through the terminal hydroxyl groups on the PEG
(HO
-
PEG
-
OH)
chains that oxidized to carbonyl groups during or after synthesis. When dimethoxy

PEG was used in
place of HO
-
PEG
-
OH, uncontrolled platinum synthesis occurred to generate bulk platinum precipitates.
Because only the OH groups at the termini of the polymers influenced particle synthesis and growth, in
working electrolytes such as H
2
SO
4

the weak carbonyl
-
platinum interactions could dissociate easily,
allowing for effective catalysis of reactions such as oxygen reduction reaction without any pretreatment.
Because spectroscopic and synthesis experiments showed that the ethylene oxide backbo
ne of PEG did
little to influence platinum nanoparticle nucleation and growth, these polymers became ideal substrates
and scaffolds upon which to attach amino acid R groups in order to investigate specific amino acid
-
platinum interactions with respect to b
oth synthesis and catalysis
;

and these studies are currently
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| MSE Summaries

underway. In addition,
several accomplishments involving new and advanced electrode materials and
nanoparticle supports for fuel cell applications have been achieved during the second year, inclu
ding the
synthesis three
-
dimensional hierarchical architectures, consisting of monolithic nanoporous gold or
silver films formed on highly ordered 3D microporous carbon supports.

Inorganic Control of Biological Self
-
Assembly: Engineering Novel Biological A
rchitectures and Redox
-
Active Protein Assemblies

Institution:

California
-
San Diego, University of

Point of Contact:

Tezcan, Akif

Email:

tezcan@ucsd.edu

Principal Investigator:

Tezcan, Faik

Sr. Investigator(s):


Students:

0 Postdoctoral Fellow(s), 3 Graduat
e(s), 3 Undergraduate(s)

Funding:

$200,000

PROGRAM SCOPE

The goals of this project are to (1) utilize combined inorganic and protein engineering approaches for
the construction of discrete or 1
-

2
-

and 3
-
D protein superstructures and frameworks, using fold
ed
proteins as building blocks and metals as interfacial joints; and (2) exploit the extensive non
-
covalent
interactions formed around the interfacial metal sites within these protein frameworks to control the
metal reactivity in ways not accessible in cur
rent synthetic inorganic and bioinorganic methodologies.
These goals combined will lead to the chemically controllable self
-
assembly of well
-
ordered
superstructures that will be used for light
-
harvesting and redox catalysis. These structures also will
prov
ide a framework for a fundamental understanding of protein self
-
assembly as well as crystal
nucleation and growth. The significance of the ability to understand and control protein self
-
assembly
cannot be overstated: proteins represent the functionally and

structurally most versatile molecular
building blocks available to an organism or to a chemist; their self
-
assembly provides a direct access to
the “nanoscale” (2
-
100 nm) not accessible by top
-
down approaches and not easily achieved by bottom
-
up approache
s using other types of building blocks; and their assembly into periodic arrays is an
absolute necessity for diffraction
-
based structure determination methods and therefore a driving force
for all biosciences. Nevertheless, the mastery over the self
-
assemb
ly of proteins has not yet reached a
level
where
discrete or
infinite

architectures with long
-
range order can be engineered
.

Our goals of using metal coordination chemistry to direct protein self
-
assembly and then to tune the
reactivity of interfacial met
als are approached at several different levels. These include the design and
synthesis of natural and non
-
natural metal
-
chelating motifs on protein surfaces to control metal
coordination; protein engineering and computational design; structural characteriz
ation of superprotein
assemblies through crystallography, electron, fluorescence, and atomic force microscopy; and the
characterization of metal reactivity and photophysics through an armament of static and time
-
resolved
spectroscopic methods.

FY 2012 HIGH
LIGHTS

We have engineered, for the first time, a protein that can self
-
assemble in a chemically controlled
fashion into 1D helical nanotubes, and 2
-

and 3
-
D arrays with crystalline order. We have also
demonstrated the ability to control the assembly of nat
ural cage
-
like proteins (like ferritin) through
MSE Summaries|
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7

engineered chemical triggers. Next, we plan to chemically control protein self
-
assembly to better
understand protein crystallization processes and to create functional protein
-
based devices.

Rigid Biopolymer
Nanocrystal Systems for Controlling Multicomponent Nanoparticle Assembly and
Orientation in Thin Film Solar Cells

Institution:

California
-
San Diego, University of

Point of Contact:

Cha, Jennifer

Email:

Jennifer.Cha@colorado.edu

Principal Investigator:

Cha,

Jennifer

Sr. Investigator(s):


Students:

1 Postdoctoral Fellow(s), 1 Graduate(s), 0 Undergraduate(s)

Funding:

$150,000

PROGRAM SCOPE

The project seeks to
direct the assembly of nanoparticles into three
-
dimensional crystals of any desired
configuration and

crystallographic orientation

using tunable DNA interactions
.
Despite the wealth of
nanoscale materials that may benefit many current and future solid state technologies, difficulties in
controlling and directing their placement and orientation into desire
d architectures ha
ve

led to
significant impediments in their applicability. Biological systems can form such structures using their
inherent molecular information as guides to assemble organic and inorganic materials into highly
organized structures ordere
d at multiple length scales. Using bio
-
inspired strategies,
the research will
control the
two
-

and three
-
dimensional
arrangement of semiconductor nanocrystals into a
seed layer
that can nucleate successive layers of single nanocrystals with long
-
range order and tunable
crystallographic orientations.
The work will elucidate how particle
-
DNA interactions influence
nanoparticle crystallographic orientation, how nanopartic
les on patterned arrays of biomolecules can
nucleate long
-
range order, and how to synthesize 2
-

and 3
-
D superlattice arrays of DNA conjugated
semiconductor nanocrystals.

FY 2012 HIGHLIGHTS

Prior to the start of this proposed research, the PI has made signi
ficant discoveries toward obtaining
highly ordered arrays of

gold nanoparticle thin films on surfaces
.

The lessons gained from these studies
were an integral part of the proposed DOE research, as they have enabled engineering well
-
ordered
binary semiconduc
tor nanocrystal arrays on surfaces for thin film solar cells. In order to apply the Au NP
biomolecular assembly process toward semiconductor materials, however, methods
wer
e needed to
synthesize DNA
-
conjugated semiconductor nanoparticles. In the first year
, the PI has studied and
created different methods to successfully conjugate semiconductor nanoparticles (CdSe, CdTe, CdS) with
DNA. Methods were developed to coat the particles with multiple ligands and maintain their stability in
the high magnesium conce
ntrations required for DNA assembly. In addition to these studies, thin films
of DNA conjugated CdSe quantum dots devices have been fabricated and tested. Initial device designs
include fabricating ITO/TiO
2
/DNA
-
CdSe/Au thin film devices. Initial tests show

that high photocurrent
densities can be produced indicating the DNA is not acting as a strongly insulating material.

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| MSE Summaries

Biological and Biomimetic Low
-
Temperature Routes to Materials for Energy Applications

Institution:

California
-
Santa Barbara, University o
f

Point of Contact:

Morse, Daniel

Email:

d_morse@lifesci.ucsb.edu

Principal Investigator:

Morse, Daniel

Sr. Investigator(s):


Students:

2 Postdoctoral Fellow(s), 1 Graduate(s), 2 Undergraduate(s)

Funding:

$350,000

PROGRAM SCOPE

The objectives of our resear
ch have been three
-
fold: (1)

t
o conduct further molecular and genetic
analyses and engineer
ing of s
ilicatein, the self
-
assembling, structure
-
directing, silica
-
synthesizing
enzyme we discovered and characterized, to better understand and manipulate in this
model system the
genetically encoded structural determinants of hierarchical self
-
assembly and the resultant emergent
properties of catalysis and templat
ing of semiconductor synthesis;
(2)

t
o use our biologically
-
inspired,
low
-
temperature, kinetically
-
cont
rolled catalytic synthesis method to optimize the
nanostructures and
performance of anodes and cathodes for high
-
performance batteries
; and

(3)

t
o use our biologically
-
inspired, low
-
temperature, kinetically
-
controlled catalytic synthesis method to further
control the
structures and properties of the layered cobalt hydroxides, analyzing these structures at the atomic level
at DOE synchrotron and neutron diffraction facilities, and analyzing the performance of these materials
as a function of structure, seeki
ng to predictively control their local ordering and the distribution of
metal
-
coordination states, and to understand and optimize the structural basis of their magnetic
behaviors.

FY 2012 HIGHLIGHTS

(1) In our genetic engineering of silicatein
,
an enzyme p
rotein that we previously discovered responsible
for making the
silica

skeletons of marine sponges
,
we accelerated the processes of mutation and natural
selection in a test tube to evolve proteins that catalyze the synthesis of semiconductors from aqueous
solutions at low temperature. Through this “directed evolution,” we developed new forms of
the

enzyme capable of producing semiconductors never before produced by living organisms.

Starting with
DNA encoding the synthesis of silicatein
,
we introduced mutat
ional changes in the DNA, and then used a
high
-
speed laser to recognize and select those mutants that produced new forms of the
enzyme that
catalyze

the synthesis of novel semiconductors such as titanium dioxide

and cadmium selenide
. Because
these semicond
uctors
ar
e toxic to living cells, the mutagenized DNA strands were introduced into
microscopic bubbles of liquid that acted as surrogates of living cells.

These microscopic
surrogates of
cells

contained all the constituents of living cells needed to expres
s the mutant DNA molecules,
synthesize the new silicatein molecules encoded by the DNA mutants, and

for the few new silicateins
with exactly the right structure

support the catalytic synthesis of the new semiconductors.


(2)
Based on the mechanism of catalytic synthesis of semiconductors we discovered in silicatein (cf.
above), we developed a biologically
-
inspired, low
-
temperature, kinetically
-
controlled catalytic method
for the synthesis of a wide variety of nanostructured se
miconductors and nanocrystalline metals. We
used this method to produce nanocomposite anodes and cathodes for high
-
performance lithium ion
batteries with rate
-
capabilities (power) higher than components made by conventional processes.

(3) Using this bio
-
i
nspired,
low
-
temperature, kinetically
-
controlled catalytic method, in conjunction with
the synchrotron and neutron scattering facilities of DOE national laboratories, we demonstrated kinetic
MSE Summaries|
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9

control of the atomic structures, metal coordination, and spin
-
co
upling states in a family of hydrotalcite
-
like layered cobalt hydroxides. We showed that kinetic control of this catalytic synthesis and the
resulting structures gives unique access to photovoltaic, photocatalytic, magnetic, and photomagnetic
behaviors of
these materials.


Miniaturized Hybrid Materials Inspired by Nature

Institution:

California
-
Santa Barbara, University of

Point of Contact:

Safinya, Cyrus

Email:

safinya@mrl.ucsb.edu

Principal Investigator:

Safinya, Cyrus

Sr. Investigator(s):

Ewert, Kai, Cal
ifornia
-
Santa Barbara, University of

Li, Youli, California
-
Santa Barbara, University of

Students:

2 Postdoctoral Fellow(s), 2 Graduate(s), 2 Undergraduate(s)

Funding:

$250,000

PROGRAM SCOPE

Our objectives are to develop a fundamental science base for the
understanding of lipid
-

and protein
-
based assembly in reconstituted biological systems and biomimetic systems with custom
-
synthesized
functional molecules. Our goals are achieved by studying complex collective interactions and their
resulting structures in

systems mimicking assembly processes occurring in cells on multiple length scales
from angstrom to micrometer.

FY 2012 HIGHLIGHTS

Recently we discovered an entirely new class of liposomes, termed block liposomes, resulting from a
stimuli
-
induced membrane
shape evolution process. Block liposomes are comprised of distinctly shaped,
yet connected, nanoscale spheres, tubes, or rods. The dynamical membrane shape evolution process
leading to their formation results from a custom
-
synthesized, highly charged dendr
itic lipid (i.e., the
stimulus). It remarkably mimics similar membrane shape changes occurring in cells

far from
equilibrium

as a result of the action of curvature
-
generating proteins, which enable specific cell
functions such as vesicle budding in endocyt
osis and intra
-
organelle trafficking. One of our aims is to
elucidate the physical
-
chemical properties of the novel lipids responsible for block liposome formation.
In particular, a series of custom
-
synthesized lipids will be used to distinguish between th
e separate
contributions of lipid headgroup charge and steric size in stabilizing block liposomes.

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| MSE Summaries

Long Range van der Waals
-
London Dispersion Interactions for Biomolecular and Inorganic Nanoscale
Assembly

Institution:

Case Western Reserve University

Point

of Contact:

French, Roger

Email:

rxf131@case.edu

Principal Investigator:

French, Roger H

Sr. Investigator(s):


Students:

0 Postdoctoral Fellow(s), 2 Graduate(s), 1 Undergraduate(s)

Funding:

$167,000

PROGRAM SCOPE

S
uccessful manipulation of nanoscale objec
ts to assemble mesosc
ale devices is a critical path to
innovative energy technologies
. A bridge is needed between the nan
o
-

and meso
-
scales where
interactions and assembly are controlled,

not just through chemical bond formation
, but also by the
primary lo
ng range interactions: van der Waals
-
London dispersion (vdW
-
Ld), polar, and electrostatic.

The ability to harness the vdW
-
Ld, electrostatic, and polar interactions is critical in defining the structure
and performance of mesoscale structures from nanoscale

objects. Due to the lack of measured or
calculated optical properties and the lack of an ability to address the realistic geometry of nano
-

and
mesoscale objects, the vdW
-
Ld interaction has been poorly characterized, rendering nanoscale and
mesoscale mate
rial design unnecessarily intractable. Now, however, we are learning to direct vdW
-
Ld
forces to guide the design and assembly of new heterogeneous inorganic and biomolecular materials.

In our collaborative project, involving Case Western Reserve Universit
y, University of Massachusetts
-
Amherst, and University of Missouri
-
Kansas City, we use first principles (
ab initio
) methods, with vacuum
ultraviolet spectroscopy, spectroscopic ellipsometry to determine spectral optical properties of
materials to construct

biomolecular/inorganic systems for new energy technologies encompassing
energy efficiency, generation, and storage. The spectral properties of the materials in multiple
configurations determine long
-
range interactions to compare with our measured interact
ion from light
and small angle x
-
ray scattering experiments. This is particularly pertinent to polar liquids, such as
water, with large contributions at low frequencies. The source materials are (bio)polymers, for example,
single and double
-
stranded DNA, p
roteins such as collagen, and inorganic materials such as silica and
aluminum phosphate.

FY 2012 HIGHLIGHTS

In
the current period

(July 1, 2011 to September 30, 2012
), we used previously calculated

optical
dispersion spectra of 64 different carbon nanotube
s

and computed the magnitude of vdW
-
Ld
interactions. I
n a
n
RSC Advances

review in press, we provide

predictive design tool
s

for manipulating the
vdW
-
Ld interactions of carbon nanotubes.

We also hosted a
Long Range Interactions Workshop

and
short course at CWRU in August 2012 to kick off this collaboration and have hosted the seminars for
public viewing.

We have initiated spectroscopic ellipsometry studies of bulk DNA films
from our UMass collaborators.
We are comparing the role of excitons on vdW
-
Ld interactions in silica glass from experimental and ab
initio calculations. The VUV
-
LPLS reflectance spectroscopy for application to collagen and DNA is
advancing, and second viri
al coefficients determined by multiple angle light scattering will be initiated
upon the arrival of the scatterometer.

MSE Summaries|
I
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11

NA
-
Mediated Evolution of Catalysts for the Production and Utilization of Alternative Fuels

Institution:

Colorado, University of

Point of

Contact:

Feldheim, Daniel

Email:

Daniel.Feldheim@Colorado.edu

Principal Investigator:

Feldheim, Daniel

Sr. Investigator(s):

Eaton, Bruce, Colorado, University of

Students:

0 Postdoctoral Fellow(s), 2 Graduate(s), 0 Undergraduate(s)

Funding:

$250,000

PROGRAM SCOPE

We are developing new methods for the discovery of catalyst materials for use in the production and
utilization of alternative fuels. The central premise of the project is that biological macromolecules can
evolve in response to selection pre
ssures to synthesize materials with desired catalytic activities. The
biological macromolecule used in the project is RNA, and RNA containing key chemical modifications
that enhance its catalytic activity. Through a process known as RNA
in vitro

selection, we have shown
that RNA sequences can evolve to mediate the formation of new materials.


Our primary objective
is to apply these methods to the discovery of materials for H
2

production and oxidation and the
conversion of CO
2

to hydrocarbon fuels
.

FY 2012 HIGHLIGHTS

RNA
in vitro

selections have now been performed in our labs to discover unique sequences that can
mediate the growth of Pt, Pd, and iron oxide nanoparticles. In studying individual sequences that
emerged from these selections we have
observed sequence
-
dependent control over particle size, shape,
and composition. In the past year
,

we also made the surprising discovery that the crystallinity of
nanoparticles formed from solutions containing RNA depends upon the presence of sequence mixtu
res.
That is, a single sequence selected from the original random RNA sequence library produced very poorly
crystalline Pd nanoparticles, while a combination of sequences that emerged from the selection yielded
crystalline nanoparticles. To our knowledge
,

this is the first example in which two biomolecules (RNA,
DNA, or peptides) selected
in vitro

work together to provide a unique chemical outcome.

Assembling Microorganisms into Energy Converting Materials

Institution:

Columbia University

Point of Contact:

Sahin, Ozgur

Email:

os2246@columbia.edu

Principal Investigator:

Sahin, Ozgur

Sr. Investigator(s):


Students:

1 Postdoctoral Fellow(s), 0 Graduate(s), 0 Undergraduate(s)

Funding:

$150,000

PROGRAM SCOPE

This project
aims to

integrate microorganisms capable
of reversible energy transduction in response to
changing relative humidity with non
-
biological materials to create hybrid energy conversion systems.
While plants and many other biological organisms have developed structures that are extraordinarily
effect
ive in converting changes in relative humidity into mechanical energy, engineered systems rarely
take advantage of this powerful phenomenon. Owing to their micrometer
-
scale dimensions, bacterial
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| MSE Summaries

spores are amenable to integration into macroscopic structure
s with desired micro
-
architectures
through directed or self
-
assembly.
T
he objective is to create robust and scalable energy conversion
materials using bacterial spores as the key biomolecular material responsible for energy conversion.
We
are going to use
a

suite of experimental platforms
,

including atomic force microscopy and micro
-
electromechanical systems
,

to investigate how to assemble hybrid spore
-
rubber latex structures that
efficiently generate electricity by converting energy from evaporation of wat
er and how the interaction
between water and spore nanostructure impos
es limits on energy conversion.

FY 2012 HIGHLIGHTS

We have started atomic force microscopy
-
based measurements to investigate maximum actuation
pressure and strain levels of spores. We ha
ve developed an experimental setup to control relative
humidity near the atomic force microscope cantilever in a dynamic manner, and we have identified
cantilever probes and tip geometries suitable for measuring the mechanical response of spores.
Prelimina
ry work density measurements have been performed. We are now extending our
measurements to different species.

DNA
-
Grafted Building Blocks Designed to Self
-
Assemble into Desired Nanostructures

Institution:

Columbia University

Point of Contact:

Kumar, Sanat

Email:

sk2794@columbia.edu

Principal Investigator:

Kumar, Sanat

Sr. Investigator(s):

Venkatasubramanian, Venkat, Columbia University

Collins, Michael, Columbia University

Students:

1 Postdoctoral Fellow(s), 3 Graduate(s), 0 Undergraduate(s)

Funding:

$454,
412

PROGRAM SCOPE

This program is aimed at developing

transformative, hybrid genetic algorithm
-
based, modeling tools,
validated by novel experiments, for designing DNA
-
grafted colloidal building blocks that will
spontaneously and reliably self
-
assemble int
o desired crystal structures. Traditionally, the creation of
ordered nanostructures involves a trial
-
and
-
error approach
;

colloidal building blocks are first
synthesized (or constructed on a computer) and then examined as to the structures they assemble
und
er desired processing conditions. These experimental/modeling strategies encounter two classes of
difficulty
.

First, these Edisonian trial
-
and
-
error methods are laborious and expensive, and do not allow
us to design nanoparticles that can assemble into a d
esired structure. Second, the growing avalanche of
data from high throughput experiments and computer simulations from the Edisonian approach have
created an informatics challenge for material design and discovery.

To make progress in this field
,

we make a break from current practice and
propose a new “inverse”
paradigm
that increases the idea flow, broadens the search horizon, and archives the knowledge from
today’s successes to accelerate those of tomorrow.

A primary feature of our approach is t
hat we shall
develop hybrid genetic algorithm based methods that will allow us to replace the trial
-
and
-
error
methodology

(forward problem
) with one that can design a building block that will spontaneously
assemble into a desired structure

(inverse problem
). While our model predictions, which will be critically
validated against novel experiments, will potentially transform this field, the more important point is
that this new methodology can eventually revolutionize the whole field of materials design.

MSE Summaries|
I
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13

To
accomplish
our

ambitious goals, we have assembled a team of expert PIs with complementary
experimental and theoretical skills who are crucial to its s
uccess.
Kumar (forward modeling), Gang
(experiments), Venkatasubramanian (GA modeling), and Collins (advan
ced machine learning algorithms)
have recently begun to collaborate on
a
-
priori

design DNA
-
grafted nanoparticles that will spontaneously
assemble into ordered arrays. The addition of the critical design component will allow this team to begin
to focus thei
r studies on systems of particular interest in the context of applications.

Optimizing Immobilized Enzyme Performance in Cell
-
Free Environments to Produce Liquid Fuels

Institution:

Columbia University

Point of Contact:

Kumar, Sanat

Email:

sk2794@columbia.
edu

Principal Investigator:

Kumar, Sanat

Sr. Investigator(s):


Students:

0 Postdoctoral Fellow(s), 1 Graduate(s), 0 Undergraduate(s)

Funding:

$120,000

PROGRAM SCOPE

Immobilization of enzymes has gained prominence in the last few decades due to its vast ind
ustrial
applications, for example, manufacture of bio
-
fuels. But, immobilization of enzymes results in reduced
enzymatic activity. The reduced activity is attributed to the structural rearrangements of the enzyme on
the immobilizing surface. The main objec
tive of this project is to get a better understanding of the
physics of protein folding and reactivity on different surfaces and degree of confinement. Our studies
indicated that proteins having a well defined native structure in bulk were stabilized upon
confinement
when the confining surface was neutral, whereas they lost their secondary structure when the confining
walls were made hydrophobic. We want to extend this study to enzyme catalyzed reactions under
confinement and crowding. Reaction ensemble Mon
te Carlo simulations were employed to study
bimolecular association and ligand substrate binding reactions. Effects of pore size and surface
interactions are also studied.

FY 2012 HIGHLIGHTS

We studied the stability of proteins inside a hydrophobic cavity
at different degrees of confinement and
surface hydrophobicity. We observed that proteins having a well defined secondary structure lost their
secondary structure upon adsorption onto a hydrophobic surface, whereas intrinsically disordered
proteins gained
structural and thermal stability upon adsorption on a hydrophobic surface. This result
was published in the
Journal of Chemical Physics

[M. Radhakrishna, S. Sharma, and S. K. Kumar, J. Chem.
Phys. 136, 114114(2012)].

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| MSE Summaries

RECOVERY ACT
-

Directed Assembly of
Hybrid Nanostructures Using Optically Resonant Nanotweezers

Institution:

Cornell University

Point of Contact:

Erickson, David

Email:

de54@cornell.edu

Principal Investigator:

Erickson, David

Sr. Investigator(s):


Students:

0 Postdoctoral Fellow(s), 1 Gradua
te(s), 0 Undergraduate(s)

Funding:

$
0 (Research was supported with prior fiscal year funding.)

PROGRAM SCOPE

In this research, we are performing a theoretical and experimental investigation into the assembly of
hybrid nanomaterials and nanostructures using

nanophotonically directed optical forces. Recently, we
have demonstrated how the electromagnetic fields in nanophotonic devices are sufficiently strong that
they can be used to physically manipulate biological (nucleic acids and proteins) and non
-
biologic
al
(nanoparticles) materials as small as a few nanometers in size. Here we will be to extend this technique
to enable the directed assembly of hybrid nanostructures that cannot be manufactured by other means
(e.g., self
-
assembly or chemical synthesis). Alt
hough we focus our work here on understanding some of
the fundamental physics behind this new approach, we envision the ultimate implementation of the
technique could be a form of “optical nanofactory” that could assemble arbitrary materials from
constitue
nt parts. An example of what we hope to do here is use an optically resonant nanotweezer to
thread gold nanoparticles inside a single carbon nanotube. We envision that structures created with this
technique could yield unique high efficiency photo
-
electric

or photo
-
thermal energy conversion devices
and enable more precise studies of the fundamental structure of nanomaterials.

FY 2012 HIGHLIGHTS

We have demonstrated the ability to trap and rotate carbon nanotubes and microtubules. This was the
first demonst
ration of our ability to actively rotate an elongated particle, which is a key requirement for
enabling the assembly described above. The paper describing these results, accepted for publication in
the journal
Nano Letters
, contains details of the experime
ntal results as well as a theoretical
interpretation.

(Bio)Chemical Tailoring of Biogenic 3
-
D Nanopatterned Templates With Energy
-
Relevant Functionalities

Institution:

Georgia Tech Research Corp

Point of Contact:

Sandhage, Kenneth

Email:

ken.sandhage@mse.gatech.edu

Principal Investigator:

Kroger, Nils

Sr. Investigator(s):

Sandhage, Kenneth, Georgia Tech Research Corp

Students:

2 Postdoctoral Fellow(s), 2 Graduate(s), 0 Undergraduate(s)

Funding:

$299,999

PROGRAM SCOPE

The overall aim of thi
s research has been to obtain fundamental understanding of (bio)chemical
methodologies that will enable utilization of the unique 3
-
D nanopatterned architectures naturally
produced by diatoms for the syntheses of advanced catalytic and structural materials

attractive for
applications in bio
-
energy conversion and energy storage.

The research is being conducted in three
MSE Summaries|
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15

research thrusts
.
Thrust 1
,
mechanistic analysis of
in vivo

immobilization of proteins in diatom biosilica
,

is directed towards elucidating t
he fundamental mechanism
(s)

underlying the cellular process of
in vivo

immobilization of proteins in diatom silica. Thrust 2
,
mechanistic analysis of shape
-
preserving reactive
conversion of diatom biosilica into high
-
surface area silicon replicas
, is aimed

at

understand
ing

the
fundamental mechanism of shape preservation and nanostructure evolution associated with the
reactive conversion of diatom biosilica templates into high surface area inorganic replicas. Thrust 3
,
immobilization of energy
-
relevant enzym
es in diatom biosilica and onto diatom biosilica
-
derived
inorganic replicas
, involves use of the

results from both Thrust 1 and 2 to
develop

strategies for
in vivo

and
in vitro

immobilization of enzymes in diatom biosilica and diatom biosilica
-
derived inor
ganic
replicas, respectively.

FY 2012 HIGHLIGHTS

Progress has been made in all three research thrusts associated with this overall aim. In Thrust 1, further
insight into the structure of the targeting peptide required for
in vivo

incorporation in diatom s
ilica has
been obtained. The penta
-
lys
-
cluster of tpSil1 has been found to act as a highly efficient silica targeting
signal (STS). An artificial penta
-
lys
-
cluster, consisting only of lysine and serine residues within a 14 amino
acid sequence, also exhibit
ed STS activity; and the reporter protein (GFP) was found to be present
throughout the girdle band region. These results demonstrate that lysine and serine residues are crucial
components of the STS. In Thrust 2, additional fundamental understanding of (1
)

the shape
-
preserving
gas/solid magnesiothermic reaction of silica (for use in generating highly porous silicon diatom replicas
for battery applications) and (2
)

the conversion of diatom silica into high surface area C and C/Pt replicas
(for use as an electrode for the oxygen reduction reaction in polymer electrolyte fuel cells) and metallic
(Au, Cu) replicas has been obtained. XRD, SEM, and TEM analyses have provi
ded insights into the kinetic
mechanism of reaction, the mechanism of stress relaxation, and the nanostructural evolution associated
with the relevant gas/solid reactions. In Thrust 3, the scope of the LiDSI method has been investigated
for enzymes that re
quire oligomerization, cofactors, and posttranslational modifications for activity.
Furthermore, chemical and physical parameters that determine the
in vitro

incorporation of the

energy
-
relevant enzyme glucose oxidase into high surface area replicas of dia
tom silica have been
identified
.

Actuation of Bioinspired, Adaptive High
-
Aspect
-
Ratio Nano
-

and Micro
-
Structures Powered by
Responsive Hydrogels: Synthesis and Modeling

Institution:

Harvard University

Point of Contact:

Aizenberg, Joanna

Email:

jaiz@seas.ha
rvard.edu

Principal Investigator:

Aizenberg, Joanna

Sr. Investigator(s):

Balazs, Anna, Pittsburgh, University of

Students:

3 Postdoctoral Fellow(s), 4 Graduate(s), 0 Undergraduate(s)

Funding:

$410,000

PROGRAM SCOPE

From the simplest bacteria to mammals, su
rvival is dependent on the organism’s ability to extract
meaningful information from a noisy environment. To accomplish this critical task, various animals have
developed sensory systems based on arrays of hair
-
like structures that act as mechanoreceptors.

These
exceptional mechanosensory systems motivate and inspire our studies. The ability to “engineer”
adaptiveness into the next
-
generation devices is becoming a key requirement and challenge in materials
science. The goal of this project is to develop ver
satile synthetic and fabrication methods compatible
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| MSE Summaries

with a wide range of materials across different length scales, leading to materials that are
multifunctional, with finely
-
tuned geometry, chemistry, and mechanics, and capable of actuation in
response to
a variety of stimuli, including temperature, humidity, and magnetic, electrical, mechanical,
and chemical cues. The creation of this novel class of actuatable nano
-

and micro
-
structured materials
will enable the bio
-
inspired design of new components and fu
nctions, especially involving motion,
propulsion, responsiveness, self
-
assembly, and dynamic control at the nano/micrometer scale. Our
experimental work is integrated with computational studies that help explain the experimental results
and guide new devel
opments.

FY 2012 HIGHLIGHTS

We have developed a robust electrodeposition method for changing the shape and aspect ratio of
microstructures, allowing us to create a multitude of masters for further replication

without resorting
to expensive and laborious li
thographic top
-
down methods. We have been exploring and exploiting a
multiphoton lithography (MPL)
approach to generat
ing hybrid actuation systems
to
pattern

pH
-

and
temperature
-
responsive hydrogels.

MPL also allows us to
pattern catalytic
Pt

and
Pd

micros
tructures
and

integrate such catalyst
s within three
-
dimensional microenvironments
, which is essential for the
design of more intricate dynamic systems.
We

have designed a new materials platform that can mediate
a variety of chemo
-
mechano
-
chemical processes
, with a possibility to build
-
in homeostatic feedback
loops. The system reversibly transduces external or internal chemical inputs into user
-
defined chemical
outputs via the “on/off” mechanical actuation of microstructures.

The complex behavior of filament
ous
hydrogel
-
muscle
-
embedded structures in response to stimuli has been extensively computationally

modeled, providing us with better understanding and predictive abilities. The work was published in top
scientific journals, such as
Nature
,
Soft Matter, JA
CS, Nature Protocols, Nano Letters, Small
,
Nano Today
.

Dynamic Self
-
Assembly, Emergence, and Complexity

Institution:

Harvard University

Point of Contact:

Whitesides, George

Email:

gwhitesides@gmwgroup.harvard.edu

Principal Investigator:

Whitesides, George

Sr. Investigator(s):


Students:

6 Postdoctoral Fellow(s), 0 Graduate(s), 0 Undergraduate(s)

Funding:

$300,000

PROGRAM SCOPE

The focus of this research program is the study of complex systems
.

We define a complex system

following the definition common in ph
ysics

as one comprising components interacting dissipatively.
Components

and
interactions

can be virtually anything; the
dissipative

constraint ensures that the
system is out of equilibrium and almost certainly shows
,
for some number of components
,
the
influences of nonlinear effects. Complex systems
,
as they evolve
,
commonly show unexpected (often
called
emergent
) behaviors. Understanding these behaviors illuminates the nature of such dissipative,
out
-
of
-
equilibrium systems, and also serves as a superb
tool for a discovery.

The program has four general goals
:


(1)
To build (e.g., in chemical terms, to synthesize) complex systems, by selecting and characterizing
individual components, adding them to the system one at a time, and observing the appearance o
f
unexpected behaviors and phenomena.

MSE Summaries|
I
-
17

(2)
To rationalize

in so far as possible

these behaviors/phenomena, and to build quantitative or semi
-
quantitative analytical models for them that reveal the underlying nonlinearities and the physical
processes that gi
ve rise to them.

(3)
To develop a mechanistic understanding (which will often combine analytical, physics
-
based
approaches with more physical
-
organic, chemically based approaches) of the systems to the point
where it is possible to use it to design and bui
ld new systems, and to control them rationally, by design.

(4)
To identify areas and problems where these systems might be applied, and to prototype (but not
fully develop) these applications.

FY 2012 HIGHLIGHTS

Our major efforts have focused on
m
olecular
-
like phenomena in assemblies of millimeter
-
sized beads
;
b
ubbles and drops
; c
harge transport through self
-
assembled monolayers
; d
ynamic microfluidic displays
for soft machines
; a
ctuation of complex motions in soft machines
; m
ultiplexed bioassays based on
m
agnetic levitation
; and i
nteracting flamelets.


Observation and Simulations of Transport of Molecules and Ions Across Model Membranes

Institution:

Illinois, University of

Point of Contact:

Murad, Sohail

Email:

murad@uic.edu

Principal Investigator:

Murad, S
ohail

Sr. Investigator(s):

Jameson, Cynthia, Illinois, University of

Students:

1 Postdoctoral Fellow(s), 1 Graduate(s), 1 Undergraduate(s)

Funding:

$0 (
Research was supported with prior fiscal year funding
.)

PROGRAM SCOPE

Transport of chemical species acro
ss membranes has universal importance, for separations, sensors,
pharmacological applications, and life itself. We propose to study transport across model membranes by
a closely coupled combination of experiments and theoretical simulations, using parallel

development of
the experimental system and the computer simulations. For the initial studies described here, we will
employ lipid bilayers supported on a solid substrate in a unique experimental setup, but the design is
sufficiently general that the trans
port of molecules across other thin film membranes can be
investigated. We will study the transport process itself, using our ability to detect chemical species along
the transport path: in the bulk medium on one side of the membrane, in the membrane, and
in the
receiving nanochannel pores on the other side. Concentration profiles of the transportable species in
these regions can be obtained in the experimental set
-
up, and these can be simulated using molecular
dynamics techniques, coarse
-
grained MD in part
icular. The nature of the experiments and simulations
are such that very detailed questions can be asked and answered, permitting fundamental
physicochemical characterization of the transport events. The molecular
-
level details that can be
provided by theo
ry are believable only if experiments provide verification in sufficient detail so that
theory is held accountable or is bounded by constraints imposed by experimental results. MD
simulations can provide details far beyond the experimental observations tha
t transport has occurred
and the number of events over a period of time. Typically this would be, for an ion channel, the total
charge transported per unit time. In contrast, we can offer much more than this.

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18

| MSE Summaries

FY 2012 HIGHLIGHTS

We have carried out simulat
ions that show how
nanoparticles interact with biological membranes
. This
is of significant importance in determining the toxicity of nanoparticles as well as their potential
applications in phototherapy, imaging
,

and gene/drug delivery. It has been shown
that such interactions
are often determined by nanoparticle physicochemical factors such as size, shape, hydrophobicity
,

and
surface charge density. Surface modification of the nanoparticle offers the possibility of creating site
-
specific carriers for both

drug delivery and diagnostic purposes.

Nanoparticles are generally considered excellent candidates for targeted drug delivery. However, ion
leakage and cytotoxicity induced by nanoparticle permeation is a potential problem in such drug
delivery schemes b
ecause of the toxic effect of many ions.
W
e have carried out a series of coarse
-
grained molecular dynamics simulations to investigate the water penetration, ion transport
,

and lipid
molecule flip
-
flop in a protein
-
free phospholipid bilayer membrane during
nanoparticle permeation. The
effect of ion concentration gradient, pressure differential across the membrane, nanoparticle size
,

and
permeation velocity have been examined in this work.

Our studies show that significant cytotoxicity can
result during a nan
oparticle penetration event, in addition to significant cell damage, as a result of lipid
flip
-
flop.

Phospholipid Vesicles in Materials Science

Institution:

Illinois, University of

Point of Contact:

Granick, Steve

Email:

sgranick@uiuc.edu

Principal
Investigator:

Granick, Steve

Sr. Investigator(s):


Students:

1 Postdoctoral Fellow(s), 2 Graduate(s), 0 Undergraduate(s)

Funding:

$229,000

PROGRAM SCOPE

This proposal has the objective to develop the science basis needed to deploy phospholipid bilayers as
functional materials in energy contexts, specifically to (1)
d
evelop an integrated molecular
-
level
understanding of what determines their dynamical shape, phase behavior and spatial organization,
mainly using a combination of fluorescence microscopy and di
rect optical measurements of long
-
range
fluctuations that characterize membrane bending stiffness and tension when nanoparticles and other
adsorbates bind;

and (2)
d
evelop understanding of their diffusion in crowded environments, which our
preliminary meas
urements suggest to be fundamentally more rapid than traditional solid particles of the
same size