Symposium Organizers
Nils Kroeger Georgia Institute of Technology
Roger Qiu Lawrence Livermore National Laboratory
Rajesh Naik Air Force Research Laboratory
David Kaplan Tufts University
DD1: Structures & Properties of Biological Materials I
Session Chairs
Tuesday PM, March 25, 2008
Room 3022 (Moscone West)
9:30 AM - **DD1.1
The Plant Cell Wall as a Passive and Active Mechanical Device.
Ingo Burgert 1 , Rivka Elbaum 2 1 , Peter Fratzl 1
1 Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Potsdam Germany, 2 , Weizmann Institute of Science, Rehovot Israel
Show Abstract10:00 AM - DD1.2
Nacre: A Unique Biomaterial Patterned by Solid Crystals.
Antonio Checa 1 , Julyan Cartwright 2
1 Estratigrafía y Paleontología, Universidad de Granada, Granada Spain, 2 Laboratorio de Estudios Cristalográficos, Consejo Superior de Investigaciones Científicas, Granada Spain
Show Abstract10:15 AM - DD1.3
Adhesive Interactions of Smooth Muscle Cells and Collagen Surfaces Studied with SPR, CARS and SIMS.
EunSeok Seo 1 , Hyegeun Min 1 , Sehwa Kim 1 , Taegeol Lee 1 , Jaeyong Lee 1 , Won Chegal 1 , DaeWon Moon 1
1 NanoBio Fusion Research Center, KRISS, Daejeon Korea (the Republic of)
Show AbstractUnderstanding of cell-surface interactions is very important for development of biological materials and understanding of cell adhesion and migration. In this report, we used Surface Plasmon Resonance (SPR), Coherent-Anti-Stokes Raman Scattering (CARS) and Secondary Ion Mass Spectrometry (SIMS) to analyze the interface between smooth muscle cells (SMCs) and collagen surfaces with different surface chemistry and structures. To study the effect of collagen surface chemistry and structure, collagen thin films prepared with native and heat denatured type I collagen and collagen-PGA copolymer micro and nano fibers were used. Due to its extreme surface specificity, SIMS measured significant differences in the surface amino acid compositions between native and denatured collagen thin films with increased hydrophobic amino acid groups in the surface layer region of collagen thin films. The different surface chemistry affects the morphology of SMCs on native and denatured collagen thin films. SPR could observe the cell adhesion layer images between collagen thin films and SMCs and the dependence of the SPR images on denaturation of collagen, the flow rate in the SPR micro-channel, and chemical detachment of SMCs.With collagen-PBA micro fibers, SIMS observed the polymer composition is not homogeneous in the axial direction with higher PGA content in the outer layer, which suggests that the cell adherent surface polymer composition of copolymer fibers can be quite different from the bulk composition. Due to the limitations in the spatial resolution of SIMS, similar surface polymer segregation could not be observed for nanofibers. However, the SMCs preferentially adhere on nanofibers than microfibers and CARS lipid imaging revealed focal cell adhesion spots localized on the nanofibers. The effect of surface chemistry and morphology on the adhesion of SMCs on collagen surface will be discussed. In summary, with complementary use of SPR, CARS and SIMS, the chemistry and structure of collagen thin films and fibers are measured and their strong effects on SMCs adhesion are observed.
10:30 AM - DD1.4
Cutting Edge Structural Protein from the Jaws of Nereis Virens.
Chris Broomell 1 , J. Waite 1
1 Marine Science Institute, UC Santa Barbara, Santa Barbara, California, United States
Show Abstract11:15 AM - **DD1.5
Dopa and Stiffness Gradients Joining Hard and Soft Tissues.
Herbert Waite 1 , Ali Miserez 2
1 Marine Science Institute, UCSB, Santa Barbara, California, United States, 2 Materials Science Department, UCSB, Santa Barbara, California, United States
Show AbstractDopa (3, 4-dihydroxyphenylalanine) is popularly associated with mussel adhesive proteins but it is also present in a wide variety of other biomaterials such as the beak of the Humboldt squid Dosidicus gigas. The beak resembles a surgical rongeur and, at its tip, represents one of the hardest and stiffest wholly organic composite materials known. As it is deeply embedded within and controlled by the soft buccal envelope, the manner by which impact forces are transmitted between beak and envelope is a matter of considerable scientific and engineering interest. The hydrated beak exhibits a large gradient in Young’s modulus, spanning more than two orders of magnitude, from ~5 GPa at the tip (rostrum) to 0.05 GPa at the base. This gradient is correlated with a chemical gradient involving mixtures of chitin and a histidine-rich protein family that contains Dopa. The protein, which reaches its highest concentration at the beak tip, restricts hydration of chitin and undergoes stabilization by formation of histidyl-Dopa cross-links. (Funded by BRP NIH grant R01 DE014672, a seed grant from the MRSEC Program of NSF under award No. DMR05-80034, and by NASA URETI)
11:45 AM - DD1.6
The Calcified Byssus of the Saddle Oyster (Anomia sp.): A Mineralized Holdfast System Containing Calcite and Aragonite.
Henrik Birkedal 1 , Jakob Eltzholtz 1 , Eiji Nishibori 2
1 Department of Chemistry and interdisciplinary nanoscience center (iNANO), University of Aarhus, Aarhus Denmark, 2 Department of Applied Physics, Nagoya University, Nagoya Japan
Show AbstractUnderwater adhesion is a problem that has met several solutions in biology. The bivalve Anomia sp. adheres to other shells or small pebbles via a calcified byssus1,2 that is roughly 3×4×7 mm. Here we investigate the design of the byssus. Scanning electron microscopy investigations show that the bottom half of the byssus, the part closest to the substrate, is replete with holes while the top part is massive. X-ray powder diffraction shows that both the aragonite and calcite polymorphs of CaCO3 are present. Most interestingly, the calcite peaks are split indicating the presence of several distinct calcite phases. Energy dispersive X-ray analysis in the SEM reveals distinct Mg distributions showing that the organism not only controls polymorph placement but also magnesium content of the calcite. Variable temperature synchrotron powder diffraction shows that the aragonite phase transforms into a single of the calcite phases, the one with the largest lattice constant, strongly indicating that the calcite phases result from variations in Mg content. Such spatial control over calcite chemistry in a single structure reflects an astonishing degree of control over the byssus mineralization process. [1] R. S. Prezant American Malacological Bulletin 1984, 2, 41-50[2] K. Yamaguchi, Marine Biology 1998, 132, 651-661.
12:00 PM - DD1.7
Studying the Organic-Inorganic Interface in Composite Biomaterials: a Solid-State NMR Approach.
Melinda Duer 1 , Serena Best 2 , Elisabeth Davies 4 , Christian Jaeger 6 , Nigel Loveridge 3 , Sergey Maltsev 6 , Rachel Murray 5 , David Reid 1 , Erica Wise 1 , Shuo Zou 2
1 Chemistry, University of Cambridge, Cambridge United Kingdom, 2 Materials Science and Metallurgy, University of Cambridge, Cambridge United Kingdom, 4 Clinical Veterinary Medicine, University of Cambridge, Cambridge United Kingdom, 6 Solid-State NMR, Federal Institute for Materials Research and Testing, Berlin Germany, 3 Medicine, University of Cambridge, Cambridge United Kingdom, 5 Centre for Equine Studies, Animal Health Trust, Newmarket United Kingdom
Show AbstractBone, tooth enamel and dentin, calcified cartilage and calcified atherosclerotic plaques are all examples of structural, organic-inorganic composites materials. As in other composite materials, the interface between the components is key in determining the material propoerties. Solid-state NMR spectroscopy is an excellent tool for studying the structure of these heterogeneous interfaces. Our work utilizes the so-called 13C {31P} REDOR experiment. This experiment enables us to identify those carbon sites (in the bound organic species) that are closest in space to phosphorus (in the mineral) by observing the effects of magnetic dipolar coupling between the respective 13C and 31P nuclei. This experiment thus provides a sensitive probe of the mineral surface bound species.In this paper, we discuss our recent finding that the mineral crystals of bone (hydroxyapatite) of bone are lined with polysaccharide, specifically, glycosaminglycan. Moreover, we find similar binding in tooth enamel and dentin and calcified cartilage and atherosclerotic plaques, suggesting a common underlying mineralization process in these tissues. In order to elucidate the role of the organic component in the mineralization process, we have examined model systems in which synthetic hydroxyapatite is either templated by glycosaminoglycans or has glycosaminoglycan bound subsequent to crystal formation and find strong evidence that the polysaccharide acts as a template for mineral formation. This is supported by further NMR experiments on equine foetal bone, where mineral formation is in its earliest stages.We have employed other NMR experiments (31P rotational resonance and rotating frame spin-lattice relaxation) to examine the binding of bisphosphonates to bone mineral. Bisphosphonates are widely used in the treatment of osteoporosis. A common goal is to develop drugs that are more selective in their binding and primarily bind to regions of bone which are being excessively eroded, whilst allowing the continuing re-modelling of other regions. Our work shows significant differences in the binding modes of different bisphosphonates and provides a means for assessing the likely efficacy of potential new drugs.
12:15 PM - DD1.8
Self-Assembly of a Robust, Self-Healing Shock Absorber: Lessons from the Mussel Byssus.
Matthew Harrington 1 , J. Waite 1
1 Dept. of MCDB , University of California, Santa Barbara, Santa Barbara, California, United States
Show AbstractMussels attach themselves to the hard substratum of the rocky intertidal zone with hundreds of shock-absorbing fibers known as byssal threads. Byssal threads have many unique and desirable mechanical properties including up to 70% hysteresis, an ultimate strain of over 100%, and most interestingly, the ability to recover stiffness and strain energy post-yield in a time-dependent self-healing process. Threads are composed almost entirely of byssal collagen, a bent-core protein, which is stored in granules in the mussel foot in a smectic liquid crystal phase. Threads self-assemble in a matter of minutes when the contents of the granules are secreted into a groove in the mussel foot, and the smectic arrangement is locked into place. Determining the molecular basis of these desirable material properties, especially self-healing and self-assembly could lead to the development of truly novel, green nanofabrication methods for producing robust, multifunctional, and self-healing materials. By extracting and purifying byssal collagen, which makes up 96% of the thread in certain regions, we take a bottom-up approach to studying the origin of the material properties of the byssal thread. Stable fibers and liquid crystalline gels have been formed in vitro from purified byssal collagen demonstrating the self-assembling nature of the protein and providing a platform for testing our hypotheses. Artificially drawn fibers retain many of the mechanical and structural properties of fully formed byssal threads suggesting that the molecular basis for the unique material properties is hidden in the primary sequence and packing of byssal collagen.
DD2: Structure & Properties of Biological Materials II
Session Chairs
Tuesday PM, March 25, 2008
Room 3022 (Moscone West)
2:30 PM - **DD2.1
Exploring the Link between Macromolecular Interactions and Self-assembly Phenomenon in Biomolecular and Biomineral Systems.
Jim De Yoreo 1
1 , Lawrence Livermore Nat'l Lab, Livermore, California, United States
Show Abstract3:00 PM - DD2.2
Understanding the Control of Protein on COM Growth and Aggregation.
Roger Qiu 1 , Matthew Weaver 1 2 , Andrzej Wierzbicki 3 , John Hoyer 4 , George Nancollas 5 , Chris Orme 1 , William Casey 2 , Jim De Yoreo 1
1 Chemistry, Materials, Earth, and Life Sciences, Lawrence Livermore National Laboratory, Livermore, California, United States, 2 Department of Chemistry, University of California, Davis, Davis, California, United States, 3 Department of Chemistry, University of South Alabama, Mobile, Alabama, United States, 4 Department of Biological Sciences, University of Delaware, Newark, Delaware, United States, 5 Department of Chemistry, University at Buffalo, Amherst, New York, United States
Show Abstract3:15 PM - DD2.3
Modeling Amino-Acid Adsorption on Calcite.
Donald Mkhonto 1 , Nita Sahai 1
1 , University of Wiscosnsin-Madison, Madison, Wisconsin, United States
Show Abstract3:30 PM - DD2.4
Observation of Nanoscopic Dissolution of Hydroxyapatite Crystals Studied by AFM.
Ki-Young Kwon 1 , Eddie Wang 2 , Seung-Wuk Lee 2
1 Physical Biosciences Devision, Lawrence Berkeley National Laboratory, Berkeley, California, United States, 2 Bioengineering, University of California, Berkeley, California, United States
Show AbstractDissolution of hydroxyapatite (HA), the inorganic component of bone, was investigated using in situ atomic force microscopy. Single crystal (100) surfaces were studied under acidic dissolution conditions. We found that local structural defects significantly influence the overall dissolution rate by forming hexagonal etch pits. The resulting pit shape is inherently dictated by the HA crystal structure and is independent of the types of acids used. However, dissolution of the flat terraces proceeds by stochastic formation of flat bottom etch pits. Overall dissolution rate is approximately 10 times faster at defect sites than at flat terraces. We also observed 0.82 nm-quantized step edge heights corresponds to the (100) interlayer distance throughout the entire dissolution processes independent of acid species and pH conditions. In addition, we calculated the different single steps energy forming hexagonal etch pits through atomistic simulation and predicted molecular structures of specific step edges. Our unprecedented nanoscopic characterization of the HA surface is significant for understanding the rapid resorption of bones during the remodeling processes and providing useful insights for the design of the novel therapies for osteoporosis and dental carries formation.
4:15 PM - **DD2.5
In Vitro Simulation of the Self-Organized Microstructure of Tooth Enamel.
George Nancollas 1 , Lijun Wang 1
1 Chemistry, University at Buffalo, Amherst, New York, United States
Show AbstractIt has been suggested that cooperative assembly and interactions between forming crystals and assembling protein/peptide is pivotal to enamel biomineralization. To understand the formation mechanisms of enamel microstructures mediated by matrix protein, amelogenin (Amel), we use a newly developed constant composition (CC) method under precisely defined thermodynamic driving forces and near-physiological conditions (σHAP=15.1, ionic strength=0.15 M, 37°C, and pH 7.40). Self-organized microstructures, compositionally and morphologically similar to natural enamel, are achieved without the use of extreme hydrothermal conditions. Amel proteins were added to supersaturated reaction solutions to achieve concentrations ranging from 0.5 to 5.0 μg mL-1. Nucleation of hydroxyapatite (HAP) was monitored by a pH electrode coupled with a single-junction Ag/AgCl reference electrode, and nucleated HAP crystallites were characterized by HRTEM. The delay (induction) time for nucleation in pure supersaturated solutions was 778 ± 30 min (n=3). However in the presence of 0.5 μg mL-1, 1.25 μg mL-1 or 5.0 μg mL-1 Amel, the induction times decreased to 705 ± 25 (n=3), 398 ± 20 (n=3), and 255 ± 20 (n=3) min, respectively, suggesting that Amel kinetically promotes HAP nucleation. Elongated ribbon-like apatite crystals were grown in the presence of 5.0 μg mL-1 Amel; whereas in the absence of Amel, HAP crystallites were randomly aggregated. In addition, an intermediate nanorod structure was successfully captured following the formation of the critical nuclei at the earliest nucleation stages. These intermediate structures further assemble by a self-epitaxial nucleation mechanism to form the final hierarchically organized microstructures. Under cooperative kinetic control, self-assembled mixtures of nucleated HAP nanoparticles and Amel nanospheres play an explicit role in the formation of organized microstructures from two dissimilar organic and inorganic nanophases during a slow crystallization process.This work was supported by the National Institutes of Health ( NIDCR grant number DE03223).
4:45 PM - DD2.6
NMR-Determined Structure of Recombinant Porcine Amelogenin (rP172): Implications for Mediation of Enamel Formation.
Katya Delak 1 , John Evans 1 , Janet Moradian-Oldak 2
1 Laboratory for Chemical Physics, Center for Biomolecular Materials Spectroscopy, New York University, New York, New York, United States, 2 Center for Craniofacial Molecular Biology, School of Dentistry, University of Southern California, Los Angeles, California, United States
Show AbstractAmelogenin is a protein principally associated with enamel formation in teeth and is typically about 20 kDa in size. Its primary sequence consists predominantly of prolines (23%), glutamines (14%), leucines (9%) and histidines (8%) and is highly conserved throughout numerous mammalian species. The primary sequence of amelogenin can be considered to have three domains: a 45 amino acid N-terminal domain that is tyrosine-rich, a central, hydrophobic domain, and C-terminal hydrophilic domain. This sequence promotes a tendency for amelogenin to self-assemble, and both nanosphere and micro-ribbon self-assembled forms of amelogenin have been observed.
There exists significant controversy regarding the structure of amelogenin in solution. Previous studies have indicated that the structure contains beta-sheet or beta-turn components as well as random coil features. This structure is largely dependent on solution pH and calcium concentration, as well as whether or not the protein is in monomeric form.
We present here our results from multi-dimensional NMR experiments on the protein structure of fully-labelled recombinant porcine amelogenin (rP172) in unbuffered solution at pH 3.8. Sequential assignments and backbone C-13 and N-15 chemical shift data were used as inputs for secondary structure calculations using TALOS software. These data were evaluated in conjunction with N-15 NOESY-HSQC experiments that were carried out to ascertain whether inter-protein contacts exist, and to evaluate whether the protein exists in monomeric or assembled form. The obtained structural features are presented in the context of the observed tendency of amelogenin to self-assemble and its capacity to influence hydroxyapatite crystal growth.
5:00 PM - DD2.7
In Silico Prediction of Functional Binding Domains of Natural Proteins.
Ersin Emre Oren 1 2 , Ram Samudrala 2 , Jeremy A. Horst 2 , Mustafa Gungormus 1 , Hanson Fong 1 , Marketa Hnilova 1 , John S. Evans 3 , Candan Tamerler 1 4 , Mehmet Sarikaya 1
1 Materials Science and Engineering Department, University of Washington, Seattle, Washington, United States, 2 Department of Microbiology, University of Washington, Seattle, Washington, United States, 3 Center for Biomolecular Materials Spectroscopy, New York University, New York, New York, United States, 4 Molecular Biology and Genetics, Istanbul Technical University, Istanbul Turkey
Show AbstractIn nature, the formation and structuring of biological hard tissues are controlled by proteins leading to complex materials with highly functional architectures. These materials include silica based skeletal units of single-celled organisms such as radiolarian and spicules of sponges, hydroxyapatite in bone and dental tissues of mammalians, iron oxide and sulfide in bacteria, and calcium carbonate minerals in mollusk shells. Emulating biology, we genetically engineer inorganic-binding peptides and use them for protein-aided manufacturing under ambient conditions that includes the steps of synthesis, nucleation, growth modification and assembly. In the molecular biomimetics approach, we normally select peptides (GEPI) that specifically bind to desired solids (e.g., quartz and hydroxyapatite) using combinatorial biology techniques (e.g., phage and cell-surface display). Recently, we developed a method that combines experimental knowledge with bioinformatics and enables us to detect sequence similarities between GEPI and any given naturally-occurring peptide/protein groups. Using the sequence-related knowledge of the combinatorially selected quartz and hydroxyapatite binders, we have generated novel scoring matrices that are used to obtain the degree of alignment between two protein sequences. Then using the scoring matrices, combinatorially selected peptides are compared with their natural protein counterparts (e.g., hydroxyapatite binding peptides versus amelogenin and quartz binding peptides versus silaffins and silicateins) to detect any possible homology and, thus, the key functional domains of the natural proteins. As a point demonstration of the approach, we show how hydroxyapatite-binding sites could be revealed in amelogenin, the most abundant protein involved in all stages of the enamel mineral formation, and used for hydroxyapatite-bases materials. Basically, such comparisons, along with the amelogenin structure predictions, provided us two putative functional domains that may primarily be involved in enamel biomineralization. The understanding of amelogenin function in enamel formation is crucial for regenerative medicine while that of silica is crucial in making silica-based practical functional materials. Mainly supported by NSF-UW/MRSEC, and also by NSF_NIRT, AFOSR-Bioinspired Materials, NSF-BioMat, NSF CAREER Award (RS), and SPO/Turkey (CT).
5:15 PM - DD2.8
Peptide Binding to Sheet Silicate and Metal Nanoparticles - Insight from Atomistic Simulation.
Hendrik Heinz 1 , Richard Vaia 2 , Rajesh Naik 2 , Barry Farmer 2
1 Department of Polymer Engineering, Univ of Akron, Akron, Ohio, United States, 2 Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson AFB, Ohio, United States
Show Abstract5:30 PM - **DD2.9
Genetic Dissection of Magnetosome Formation and Magnetite Biomineralization.
Arash Komeili 1
1 Plant and Microbial Biology Dept, University of California-Berkeley, Berkeley, California, United States
Show Abstract
Symposium Organizers
Nils Kroeger Georgia Institute of Technology
Roger Qiu Lawrence Livermore National Laboratory
Rajesh Naik Air Force Research Laboratory
David Kaplan Tufts University
DD3: Bioenabled Materials I
Session Chairs
Wednesday AM, March 26, 2008
Room 3022 (Moscone West)
9:30 AM - DD3.0
First Evidence of van der Waals and Capillary Adhesion through Nanofibers in a Marine Species.
Albert Lin 3 , Ralf Brunner 1 2 , Po-Yu Chen 3 , Frank Talke 1 2 , Marc Meyers 1 3
3 Materials Science and Engineering, University of California - San Diego, La Jolla, California, United States, 1 Department of Mechanical and Aerospace Engineering, University of California - San Diego, La Jolla, California, United States, 2 Center for Magnetic Recording Research, University of California - San Diego, La Jolla, California, United States
Show Abstract9:45 AM - **DD3.1
Bioinspired Synthesis of Novel Nanostructures Based on S-layer Lattices.
Dietmar Pum 1 , Nicola Ilk 1 , Bernhard Schuster 1 , Uwe Sleytr 1
1 Center for Nanobiotechnology, University of Natural Resources and Applied Life Sciences, Vienna Austria
Show AbstractOne of the most challenging research areas is currently found at the interface between biology and physics. In particular, bottom-up fabrication and self-assembly of molecular building blocks has grown into a scientific and engineering discipline crossing the boundaries of several established fields. Two-dimensional bacterial surface layer proteins (S-layer proteins) are versatile assembly systems providing a structural basis for a complete supramolecular construction kit, involving all major species of biological macromolecules (proteins, lipids, glycans, and nucleic acids). S-layers are the most commonly observed cell surface structures in prokaryotic organisms (bacteria and archaea). They are composed of a single protein or glycoprotein species (Mw = 40 to 200 kDa) and exhibit either oblique, square or hexagonal lattice symmetry with unit cell dimensions in the range of 3 to 30 nm. S-layers are generally 5 to 10 nm thick. They represent highly porous protein meshworks with pores of uniform size and morphology in the 2 to 8 nm range. One of the key features of isolated S-layer proteins is their intrinsic tendency to self-assemble into two-dimensional arrays in suspension, at solid supports (e.g. silicon wafers), at the air-water interface, at floating lipid monolayers and at vesicles (liposomes and nanocapsules). This presentation is focussing on the reassembly of native and genetically functionalized S-layer proteins and, in particular, on their use as matrices for the templated assembly of molecules and nanoparticles into ordered arrays. S-layer fusion proteins with different functionalities play a key role in this work since they allow to turn into novel routes in the development of biological templating, specific biomineralisation strategies on surfaces, affinity matrices, diagnostics, biocompatible surfaces, and microcarriers.
10:15 AM - **DD3.5
Self-Assembled Nanotubes from Aromatic Short Peptide Derivatives.
Rein Ulijn 1
1 School of Materials & MIB, University of Manchester, Manchester United Kingdom
Show AbstractWe will present a versatile supramolecular architecture for nanomaterials based on aromatic short peptide derivatives. These peptide derivatives self-assemble into defined nanostructures (tubes, fibres, sheets) via anti-parallel β-sheets that interlock through π-π stacking interactions. The twisted nature of the β-sheets causes formation of handed structures with highly tuneable dimensions. The general validity of the proposed model will be discussed using spectroscopic and microscopic data obtained for a range of short peptides (single amino acids up to pentamers) that are modified with aromatic residues. The morphology and dimensions of the resulting nanostructures is dictated both by the chemical nature of the amino acid and aromatic building blocks and the route of self-assembly, highlighting the versatility of aromatic short peptide derivatives. The proposed molecular architectures open up a number of biological and technological applications. Certain combinations of peptide derivatives gave rise to stable bioactive hydrogels that could be used to control and direct cellular behaviour in 3D cell culture for a range of cell types. For emerging technical applications of peptide nanomaterials, defect free structures with enhanced complexities are desirable. We demonstrate that biocatalysis can be exploited to direct self-assembly of these nanostructures, giving rise to higher levels of control of the self-assembly process resulting in sructures with fewer defects.
11:15 AM - **DD3.6
SP1 As A Thermostable Protein Scaffold Building Block For Self-Assembly Of Composite Materials.
Oded Shoseyov 1 , Arnon Heyman 1 , Shaul Lapidot 1 , Sigal Meirovitch 1 , Izhar Medalsy 2 , Or Dgany 1 , Oron Bet Or 1 , Arie Altman 1 , Danny Porath 2
1 The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, and the Otto Warburg Minerva Center for Agricultural Biotechnology, Faculty of Agricultural, Food and Environmental Quality Sciences, The Hebrew University of Jerusalem, Rehovot Israel, 2 Physical Chemistry Department, Hebrew University of Jerusalem, Jerusalem Israel
Show AbstractSelf-assembly is a prerequisite for the fabrication of nanoscale structures. Biomolecules in general and proteins in particular are capable of self-assembling into a wide variety of structures that can be readily manipulated and functionalized. An ideal protein scaffold provides a rigid folding unit, which spatially brings together different functional domains. SP1 is a thermo-stable homo-oligomeric protein. This ring-shaped homododecamer protein is utilized to display both nano-particles and protein domains in a pre-defined manner. Using genetic engineering, the protein was designed to bind various molecules and nano particles such as gold, silicon and titanium, assemble two and three dimensional arrays and structures, and display various protein domains. Glucose oxidase (GOx) gene was fused in-frame to SP1. The fusion protein self assembled to active multienzyme nanotube particles containing hundreds of GOx molecules per tube. In another aspect of our work we study self assembly of composite materials made of cellulose and polymeric proteins such as spider silk and resilin fused to a Cellulose Binding Domain (CBD). Recombinant CBD-silk protein was produced in transgenic plants. A cDNA coding for resilin gene was cloned from Drosophila melanogaster. Recombinant resilin proteins, with and without CBD were expressed in E. coli. We have shown that these proteins can bind to cellulose and chitin and polymerized into a rubber-like material by photochemical cross-linking. Future aspects of combining SP1 scaffold and CBD-fused to polymeric proteins will be discussed.
11:45 AM - DD3.7
Exploiting Amyloidogenicity for the Fabrication of CdS and PbS Semiconducting Nanowires.
Sonal Padalkar 1 2 , John Hulleman 3 , Seung Min Kim 1 2 , Jean-Cristophe Rochet 3 , Eric Stach 1 2 , Lia Stanciu 1 2
1 School of Materials Engineering , Purdue University, West Lafayette, Indiana, United States, 2 Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana, United States, 3 Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana, United States
Show AbstractCadmium sulfide and lead sulfide semiconducting nanowires have been fabricated for the first time by exploiting a general property of proteins, amyloidogenicity. The diameter of the CdS and PbS nanowires were tuned in the range starting from ~50 nm to ~350 nm by changing the process parameters. The nanowires were characterized by field emission scanning electron microscopy, UV-VIS spectroscopy, transmission electron microscopy, electron energy loss spectroscopy and high resolution transmission electron microscopy. The nanowires appeared continuous and were composed of several nanocrystals, 3-6nm in diameter. The diffraction patterns revealed a zinc blende structure for CdS and a rock salt structure for PbS nanowires. The UV-VIS absorption peak for CdS nanowires was observed around 465nm which falls in the visible wavelength regime, indicating a potential application in photoluminescent devices.
12:00 PM - DD3.8
DNA – Directed Synthesis of ZnO Nanowires.
Petia Atanasova 1 , Micha Jost 1 , Hanling Li 1 , Jerzy Golczewski 1 , Peter Gerstel 1 , Wilfried Sigle 1 , Peter A. van Aken 1 , Joachim Bill 1
1 , Max-Planck Institute for Metal Research, Stuttgart Germany
Show Abstract12:15 PM - DD3.9
Cellulose Nanocrystal as a Green Reactor for Templated Synthesis of Ordered Interfacial Nanostructures.
Yongsoon Shin 1 , Gregory Exarhos 1
1 , Pacific Northwest National Lab, Richland, Washington, United States
Show Abstract12:30 PM - DD3.10
Lithography with Life: A New Means of Patterned Cellular Integration into Self-Assembled Nanostructures.
Eric Carnes 1 2 , Carlee Ashley 1 2 , DeAnna Lopez 1 , Cynthia Douthit 1 , Shelly Karlin 1 , Jennifer Pelowitz 2 , Alex Capecelatro 4 , Jason Harper 3 , Darren Dunphy 1 , Hattie Gresham 2 , Graham Timmins 2 , C. Brinker 1 2 3
1 Chemical and Nuclear Engineering, University of New Mexico, Albuquerque, New Mexico, United States, 2 Health Sciences Center, University of New Mexico, Albuquerque, New Mexico, United States, 4 , University of California, Los Angeles, Los Angeles, California, United States, 3 , Sandia National Laboratories, Albuquerque, New Mexico, United States
Show AbstractPatternable cell immobilization is an essential feature of any solid-state device designed for interrogating or exploiting living cells. Immobilized cells must remain viable in a robust matrix that promotes fluidic connectivity between the cells and their environment while retaining the ability to establish and maintain necessary chemical gradients. A suitable inorganic matrix can be constructed via evaporation-induced self-assembly of nanostructured silica, in which phospholipids are used in place of traditional surfactant structure-directing agents in order to enhance cell viability and to create a coherent interface between the cell and the surrounding three-dimensional nanostructure. We have developed several distinct cell immobilization and patterning strategies that have tailorable properties; the validity of each patterning method has been demonstrated with Gram-positive and Gram-negative bacteria, yeast, and mammalian cells. Biocompatible selective wetting techniques are used, as well as aerosol deposition, ink-jet printing, and robo-casting. Viability of cells immobilized using the different patterning techniques has been assessed and various cellular functionalities have been confirmed. Ability of the immobilized cells to establish relevant gradients of ions or signaling molecules has been characterized. Cell-to-cell communication within the matrices has also been investigated and metabolism of the cells immobilized has been monitored. With many of these patterning techniques, cells are also able to actively integrate into the host matrix in a manner similar to the cell-directed assembly process we recently reported (Science 21, July 2006). This active integration of cells into a host matrix not only provides enhanced viability, but also provides a unique way of integrating bio- and nano-materials. In this instance, a nanomaterial with bulk functional properties can serve as a host matrix, maintaining its functionality while patterned cells create their own microenvironments. This provides not only new platforms for cellular interrogation, but also a novel yet simple procedure for creating new bionanomaterials.
12:45 PM - DD3.11
Higher Throughput Janus Functionalization of Gold Nanorods.
Robert MacCuspie 1 2 , Kyoungweon Park 1 2 , Rachel Kolesnikov-Lindsay 1 3 , Folusho Oyerokun 1 2 , Andrea Elsen 1 4 , Rajesh Naik 1 , Richard Vaia 1
1 Nanostructured and Biological Materials Branch, Air Force Research Lab, Wright-Patterson AFB, Ohio, United States, 2 , National Research Council, Washington, District of Columbia, United States, 3 , Massachusetts Institute of Technology, Cambridge, Massachusetts, United States, 4 Chemistry Dept, Wright State University, Dayton, Ohio, United States
Show AbstractJanus particles offer unique functionality; for example the use of micronscale Janus spheres for electronic paper. At the nanoscale, reproducible scalable fabrication of asymmetric particles is one of the key enabling technologies and to develop hybrid “top-down” - “bottom-up” assembly processes. For example, focused ion beam and lithographic techniques are utilized to form arrays of metal nanorod pairs, a common motif for negative index of refraction materials. The use of Janus nanorods to form protoassemblies (2-4 rod clusters) provides a self-assembly bottom-up alternative. Commonly, Janus particles are synthesized using a masking step, either self masking afforded by directional vapor deposition or substrate masking to block modification chemistry. Both rely on 2D planar substrates that minimizes ultimate throughput. Reversible surface absorption of gold nanorods onto colloids such as silica or ion-exchange resins with diameters from 200nm to 300um is examined as a viable means to increase available masking surface area for a reactive solution. The relationship between solution conditions such as pH, electrolyte content, and sonication on the effects of the reversibility of nanorods absorption and the ultimate surface density are discussed. The ligand size was found to provide a limited range of tunability on the Janus ligand exchange when using surface masks, and was found to agree well with geometrical-based theoretical predictions. The effect of this tuned degree of Janus coverage was found to affect the protoassemblies of rods, with the greater the attractive coverage the larger the protoassemblies formed. Computational predictions of 2D disc assembly agreed well with the structures observed by TEM, and demonstrate that the synthesis of self-assembling nanorods pairs is scalable, enabling affordable synthesis of enough rod pairs to characterize bulk material properties.
DD4: Bioenabled Materials II
Session Chairs
Wednesday PM, March 26, 2008
Room 3022 (Moscone West)
3:00 PM - **DD4.1
Biointerfacial Aspects of Mussel Adhesion and Simple Biomimetic Analogs as Versatile Coatings.
Phillip Messersmith 1 , Haeshin Lee 1 , Junsung Rho 1 , Shara Dellatore 2 , William Miller 2
1 Biomedical Engineering, Northwestern University, Evanston, Illinois, United States, 2 Chemical and Biological Engineering, Northwestern University, Evanston, Illinois, United States
Show AbstractMussels are famous for their ability to permanently adhere to a wide variety of wet surfaces, such as rocks, metal and polymer ship hulls, and wood structures. To accomplish this through specialized proteins collectively referred to as mussel adhesive proteins (MAPs). The biointerfacial aspects of MAPs is being revealed through the use of single molecule force measurements. The results provide insight into the adhesive roles of key amino acids found in these proteins, and this information is being incorporated into designs of biomimetic polymers for a variety of applications. Small molecule analogs of MAPs can be used to apply thin functional films onto virtually any material surface using a facile approach. These coatings have a variety of potential uses in microelectronics, water treatment, prevention of environmental biofouling, and for control of biointerfacial phenomena at the surface of medical/diagnostic devices.
3:30 PM - DD4.2
Fabrication of Hydroxyapatite-collagen Composites with Bone Nanostructure via a Fluidic Amorphous Precursor to Hydroxyapatite.
Taili Thula 1 , Sang Soo Jee 1 , Laurie Gower 1
1 Materials Science and Engineering, University of Florida, Gainesville, Florida, United States
Show Abstract3:45 PM - DD4.3
Bioengineering of Bacterial Magnetic Particles and its Application to Ligand Screening.
Tomoko Yoshino 1 , Chihiro Kaji 1 , Tadashi Matsunaga 1
1 Department of Biotechnology, Tokyo University of Agriculture and Technology, Tokyo Japan
Show Abstract4:15 PM - DD4.5
Biomimetic Formation of Inorganic Nanoparticles on Free-standing Membranes.
Eugenia Kharlampieva 1 , Joseph Slocik 2 , Rajesh Naik 2 , Nils Kroeger 3 1 , Vladimir Tsukruk 1
1 Materials Science & Engineering, Georgia Institute of Technology, Atlanta, Georgia, United States, 2 Materials and Manufacturing Directorate Wright-Patterson AFB, Air Force Research Laboratory, Dayton, Ohio, United States, 3 School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia, United States
Show Abstract4:30 PM - DD4:BIOEN-II
Break
4:45 PM - **DD4.6
Biologically Enabled Processing of Chemically-Tailored Three-Dimensional Nanostructured Assemblies.
Ken Sandhage 1 , Zhihao Bao 1 , Michael Weatherspoon 1 , Samuel Shian 1 , Matthew Dickerson 3 , Eric Ernst 1 , Zhitao Kang 1 , Ye Cai 1 , Guojie Wang 2 , Simon Jones 2 , Seth Marder 2 , Christopher Summers 1 , Meilin Liu 1
1 Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia, United States, 3 Biotechnology Group, Air Force Research Laboratory, Dayton, Ohio, United States, 2 Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia, United States
Show Abstract5:15 PM - DD4.7
Synthetic Lignin-polysaccharide Complexes: Novel Bionanoparticles Inspired from Wood.
Bernard Cathala 1 , Abdellatif Barakat 2 , Cedric Gaillard 1 , Didier Lairez 3 , Brigitte Chabbert 2 , Isabelle Capron 1 , Moustafa Hamieh 1 , Herve Bizot 1
1 UR1268 Biopolymères Interactions Assemblages, Institut National de la Recherche Agronomique (INRA), F-44300 Nantes France, 2 UMR614 Fractionnement des Agro-Ressources et Emballage, Institut National de Recherche agronomique, INRA, F-51100 Reims France, 3 Laboratoire Léon Brillouin, CEA/CNRS, CEA Saclay, 91191 Gif-sur-Yvette France
Show Abstract5:30 PM - DD4.8
Using Synthetic Collagen and Peptide Nanofiber Templates for Biomimetic Assembly of Functional Nanomaterials.
Song Jin 1
1 , University of Wisconsin-Madison, Madison, Wisconsin, United States
Show AbstractNature adopts a superior approach to nanomaterials assembly in biomineralization. We apply the principles derived from biomineralization processes to the assembly of nanoscale functional materials into nanoscale systems. By carefully controlling surface organic molecules to promote heterogeneous nucleation at designated regions while completely suppressing homogeneous nucleation elsewhere, we enable the controlled bottom-up assembly of inorganic nanomaterials directly from solution. Following this principle, arrays of semiconductor materials onto flexible polymer substrates have been successfully assembled and utilized for macroelectronic applications. In this talk, I will focus on our recent explorations using self-assembled synthetic collagen protein and beta–peptide fibrils with known molecularly controlled sequence to specifically nucleate and assemble diverse family of inorganic nanocrystals, such as Au, CdS, ZnS, PbS, and ZnO. Ultimately, we would like to achieve programmable assembly of nanoscale materials by molecular design.
5:45 PM - DD4.9
Characteristics and Technical Applications of Cellulose Nanocomposites.
Tanja Zimmermann 1 , Nico Bordeanu 1 , Christian Eyholzer 1 , Klaus Richter 1
1 Wood Laboratory, EMPA, Duebendorf Switzerland
Show Abstract