FROM: NATIONAL SCIENCE FOUNDATION BIOLOGY
Learning from biology to create new materials
Researcher studies crystal growth that may lead to biomaterials for both and tooth repair
In nature, some organisms create their own mineralized body parts--such as bone, teeth and shells--from sources they find readily available in their environment. Certain sea creatures, for example, construct their shells from calcium carbonate crystals they build from ions found in the ocean.
"The organism takes brittle carbonate and turns it into a structural shape that protects it from predators, and from being bashed against the rocks," says Lara Estroff, an associate professor of materials science and engineering at Cornell University. "There is much scientific interest in how the organism controls the crystal growth, and what mechanisms are involved in strengthening and toughening the shells, especially in comparison to their components, which are brittle."
Researchers such as Estroff are very interested in synthesizing this kind of biology in the lab, and creating new organic and inorganic materials that mimic the "biomineralization" that occurs in nature, so they can gain a better understanding of how these natural processes work.
"We are trying to learn the techniques from the organisms, and apply them in the laboratory," says the National Science Foundation (NSF)-funded scientist, a synthetic chemist by training. "Part of it is creating simplified systems so that we can tease apart the more complicated mechanisms that are going on in biology. I am not recreating biology in the lab. I am learning from biology to create new materials."
Estroff's primary research focus is to discover the role of gels in crystal formation. Hydrogels, which are gels made in water, similar to Jell-O®, are involved in a number of natural biological systems, including the mother-of-pearl in mollusk shells, tooth enamel in mammals, even otoconia, which are tiny particles found in human ears. These substances are composed of both organic and inorganic materials; often the organic components form a gel. Estroff wants to know their purpose.
"Is there something special about a hydrogel in directing crystal growth?" she asks. "Does it change properties? Is it somehow responsible for giving rise to organic-inorganic composites?"
Understanding and controlling crystal growth is very important in many industrial fields, chief among them the manufacture of pharmaceuticals, since many drugs are in crystalline form, and "it's of vast importance to know how to modulate the solubility of crystals and how they pack into tablets," she says.
There also may be potential applications in producing biomaterials for bone and tooth repair, and in creating more functional inorganic materials, such as substances structured at the nanoscale that could enhance energy storage, for example in batteries. "Being able to manipulate these crystal structures down to the nanoscale opens up a lot of opportunities," she says.
Estroff is conducting her research under an NSF Faculty Early Career Development (CAREER) award, which she received in 2009. The award supports junior faculty who exemplify the role of teacher-scholars through outstanding research, excellent education and the integration of education and research within the context of the mission of their organization. NSF is funding her work with $472,773 over five years.
The project focuses on observations, both in nature and in the laboratory, of macroscopic, single crystals with incorporated polymer fibers and other macromolecules. The project aims to understand the mechanisms by which these polymer networks become incorporated into macroscopic, single crystals.
Her lab, in studying crystal growth mechanisms in gels and their relationship to biomineralization, is trying to answer at least three questions. "First, what is the internal structure of these crystals, and where does the gel material become trapped?" she asks. "Second, can we understand the mechanism of how it is trapped to control how much is trapped? And, third, what effect does this material have on the mechanical properties of the crystals?"
To find the answers, her team developed a synthetic analog to the biological system. Using agarose, a more purified form of the gel agar-agar, they grew their own crystals in the lab, then compared them to crystals grown without gel in an ordinary water-based solution, and later to natural biological crystals.
During the process, they ran a high resolution electron tomography scan of their samples, creating a three-dimensional image of the gel-grown crystal, which "was the first time that people had actually seen how the organic phase can be incorporated in the crystal," she says. "A crystal is an order array of ions, and a polymer is a floppy, poorly-defined blob. How do you accommodate this floppy blob into this ordered array?"
In comparing their synthetic crystals to natural ones, "there were similarities and differences," she says. "We now have the best image of how these objects are incorporated and now can start asking questions about the structure-property relationships, including how this internal structure translates into changes in the mechanical properties. We've been poking at the crystals and looking at the response."
As it turns out, "these organic inclusions mechanically strengthen and toughen the material in both biological crystals and synthetic crystals," she says. "The organic material that is trapped within the crystals makes them stronger and harder--more resistant to fracture--than their geologic counterparts with no organic material."
The researchers' next step is to synthesize other materials. "We'd like to find out if we can grow different types of crystals in different types of gels," she says. "We're now pursuing that route."
As part of the grant's educational component, Estroff teaches a course on biomineralization for both graduate students and undergraduates. "One of my goals is to get them reading primary literature and analyzing it," she says. "They also go out and look for biomineralizing organisms on campus. They go to local streams and bring them back to the lab."
She also is trying to recruit more female students to her department. She is the faculty advisor to a group known as WIMSE, which stands for Women in Materials Science and Engineering, and has organized a mentoring program where freshmen and sophomores are paired with juniors and seniors who, in turn, are paired with graduate students. The enrollment of women in the materials science and engineering major has grown from 10 percent to 30 percent during the last five years.
"Having a group creates a critical mass," she says. "It's really had a positive impact."
-- Marlene Cimons, National Science Foundation
Investigators
Lara Estroff
Related Institutions/Organizations
Cornell University
Showing posts with label NEW MATERIALS. Show all posts
Showing posts with label NEW MATERIALS. Show all posts
Monday, February 17, 2014
Tuesday, January 14, 2014
NEW MOLECULES MAY FUNCTION AT NANOSCALE
FROM: NATIONAL SCIENCE FOUNDATION
New hybrid molecules could lead to materials that function at the nanoscale
Research could lead to improvements in large-scale water purification and solar power
Synthetic chemists today have the ability to construct molecules of almost any atomic composition, creating new materials with any number of promising applications that range from sustainable energy and environmental remediation, to high-performance electronics.
"It is possible to finely tune the properties of molecules through chemical synthesis to achieve just the right balance of properties needed," says Jonathan Rudick, an assistant professor of chemistry at Stony Brook University. "For example, through chemical synthesis, we can select ranges of the solar spectrum that a molecule will absorb, which has been essential for progress made in the area of organic molecules for solar power."
The National Science Foundation (NSF)-funded scientist is studying a class of molecules known as dendrons, highly branched molecules shaped like wedges or cones, which pack together to form circular or spherical assemblies with nanoscale dimensions. His group aims to develop a new class of nanoscale materials that can be processed like conventional synthetic polymers, yet retain the high structured order found in proteins.
One potential benefit of their work could be in developing a low-cost, low-weight and compact material that could be used to purify large volumes of water, and prove valuable in developing countries where potable water is difficult to find. It also could be useful in large scale water treatment facilities "where you need to be able to purify large volumes quickly, and the less membrane it takes to do that, the better," he says.
This requires creating the tiniest of channels for the water to pass through, which is not as simple as it sounds.
"The composition lining of the hole determines whether the water will go through," he says. "When you get a hole down to being the size of a molecule, then the interactions between the atoms in the water molecule and the atoms that line the hole become critical as to whether or not the water will go through. It's not like shooting water through a faucet."
Dendrons pose a special challenge in that "there is very little order to how the atoms are arranged within their assembly," making it difficult for scientists to manipulate the atoms, Rudick says.
However, peptides, on the other hand, another class of molecules "can take on a helical conformation, in which the atoms are arranged like a spiral staircase," with known locations for each atom, he explains. "Because the location of each atom in the helical molecule is known, we can accurately anticipate the positions of atoms in bundles of helical peptides."
Their approach, then, is to attempt to design a hybrid using the best features of each. The result would be a new class of molecules, dendronized helix bundle assemblies.
"We anticipate that this new class of materials will allow us to more accurately understand how materials function at the nanoscale," he says.
"We are trying to prove the concept that we can create a material where you can have atomic level control," he adds. "We synthesize new materials. We make these new materials, and we are characterizing the structure of films that can be made from them."
Dendronized helix bundle assemblies "represents a class of molecules that has never been made before," he says. "It's a class of polymer with a perfectly branched molecular structure. We refer to them as 'bio hybrid molecules,' because part is something found in nature, and the other part is synthetic. We are covalently attaching sequences of amino acids that might be found in helical proteins in nature to dendrons."
He is conducting his research under a NSF Faculty Early Career Development (CAREER) award. The grant supports junior faculty who exemplify the role of teacher-scholars through outstanding research, excellent education, and the integration of education and research within the context of the mission of their organization. NSF is funding his work with about $500,000 over five years.
As part of the grant's educational component, his lab is working with a local high school to teach students about liquid crystals and other forms of soft matter.
Dendronized helix bundle assemblies also could have a major impact in the development of molecular materials for solar power, he says.
"The active components in organic photovoltaic materials are organic molecules that can absorb light called chromophores," he explains. "The arrangement of chromophores in a film plays an important role in determining whether an absorbed photon of light is transformed into energy we can use.
"Furthermore, the best arrangement of chromophores is not yet known, and will likely vary depending on the particular chromophore being used," he adds. "By incorporating chromophores within the helical bundle portion of our hybrid molecular materials, we will be able to systematically explore how to optimize the performance of solar conversion materials."
-- Marlene Cimons, National Science Foundation
Investigators
Jonathan Rudick
New hybrid molecules could lead to materials that function at the nanoscale
Research could lead to improvements in large-scale water purification and solar power
Synthetic chemists today have the ability to construct molecules of almost any atomic composition, creating new materials with any number of promising applications that range from sustainable energy and environmental remediation, to high-performance electronics.
"It is possible to finely tune the properties of molecules through chemical synthesis to achieve just the right balance of properties needed," says Jonathan Rudick, an assistant professor of chemistry at Stony Brook University. "For example, through chemical synthesis, we can select ranges of the solar spectrum that a molecule will absorb, which has been essential for progress made in the area of organic molecules for solar power."
The National Science Foundation (NSF)-funded scientist is studying a class of molecules known as dendrons, highly branched molecules shaped like wedges or cones, which pack together to form circular or spherical assemblies with nanoscale dimensions. His group aims to develop a new class of nanoscale materials that can be processed like conventional synthetic polymers, yet retain the high structured order found in proteins.
One potential benefit of their work could be in developing a low-cost, low-weight and compact material that could be used to purify large volumes of water, and prove valuable in developing countries where potable water is difficult to find. It also could be useful in large scale water treatment facilities "where you need to be able to purify large volumes quickly, and the less membrane it takes to do that, the better," he says.
This requires creating the tiniest of channels for the water to pass through, which is not as simple as it sounds.
"The composition lining of the hole determines whether the water will go through," he says. "When you get a hole down to being the size of a molecule, then the interactions between the atoms in the water molecule and the atoms that line the hole become critical as to whether or not the water will go through. It's not like shooting water through a faucet."
Dendrons pose a special challenge in that "there is very little order to how the atoms are arranged within their assembly," making it difficult for scientists to manipulate the atoms, Rudick says.
However, peptides, on the other hand, another class of molecules "can take on a helical conformation, in which the atoms are arranged like a spiral staircase," with known locations for each atom, he explains. "Because the location of each atom in the helical molecule is known, we can accurately anticipate the positions of atoms in bundles of helical peptides."
Their approach, then, is to attempt to design a hybrid using the best features of each. The result would be a new class of molecules, dendronized helix bundle assemblies.
"We anticipate that this new class of materials will allow us to more accurately understand how materials function at the nanoscale," he says.
"We are trying to prove the concept that we can create a material where you can have atomic level control," he adds. "We synthesize new materials. We make these new materials, and we are characterizing the structure of films that can be made from them."
Dendronized helix bundle assemblies "represents a class of molecules that has never been made before," he says. "It's a class of polymer with a perfectly branched molecular structure. We refer to them as 'bio hybrid molecules,' because part is something found in nature, and the other part is synthetic. We are covalently attaching sequences of amino acids that might be found in helical proteins in nature to dendrons."
He is conducting his research under a NSF Faculty Early Career Development (CAREER) award. The grant supports junior faculty who exemplify the role of teacher-scholars through outstanding research, excellent education, and the integration of education and research within the context of the mission of their organization. NSF is funding his work with about $500,000 over five years.
As part of the grant's educational component, his lab is working with a local high school to teach students about liquid crystals and other forms of soft matter.
Dendronized helix bundle assemblies also could have a major impact in the development of molecular materials for solar power, he says.
"The active components in organic photovoltaic materials are organic molecules that can absorb light called chromophores," he explains. "The arrangement of chromophores in a film plays an important role in determining whether an absorbed photon of light is transformed into energy we can use.
"Furthermore, the best arrangement of chromophores is not yet known, and will likely vary depending on the particular chromophore being used," he adds. "By incorporating chromophores within the helical bundle portion of our hybrid molecular materials, we will be able to systematically explore how to optimize the performance of solar conversion materials."
-- Marlene Cimons, National Science Foundation
Investigators
Jonathan Rudick
Friday, August 23, 2013
NATURE AND INNOVATIVE MATERIALS
FROM: NATIONAL SCIENCE FOUNDATION
Inspired by nature: textured materials to aid industry and military
Innovation Corps team developed metals and plastic that repel water, capture sunlight and prevent ice build-up
The lotus leaf has a unique microscopic texture and wax-like coating that enables it to easily repel water. Taking his inspiration from nature, a University of Virginia professor has figured out a way to make metals and plastics that can do virtually the same thing.
Mool Gupta, Langley Distinguished Professor in the university's department of electrical and computer engineering, and director of the National Science Foundation's (NSF) Industry/University Cooperative Research Center for Lasers and Plasmas, has developed a method using high-powered lasers and nanotechnology to create a similar texture that repels water, captures sunlight and prevents the buildup of ice.
These textured materials can be used over large areas and potentially could have important applications in products where ice poses a danger, for example, in aviation, the automobile industry, the military, in protecting communication towers, blades that generate wind energy, bridges, roofs, ships, satellite dishes, and even snowboards.
In commercial and military aviation, for example, these materials could improve airline safety by making current de-icing procedures, which include scraping and applying chemicals, such as glycol, to the wings, unnecessary.
For residents in the frigid northeast, many of whom rely on satellite systems, "it could mean they won't lose their signal, and they won't have to go outside with a hammer and chisel and break off the ice," Gupta says.
The materials' ability to trap sunlight also could enhance the performance of solar cells.
Gupta and his research team first made a piece of textured metal that serves as a mold to mass-produce many pieces of plastic with the same micro-texture. The replication process is similar to the one used in manufacturing compact discs. The difference, of course, is that the CD master mold contains specific information, like a voice, whereas, "in our case we are not writing any information, we are creating a micro-texture," Gupta says.
"You create one piece of metal that has the texture," Gupta adds. "For multiple pieces of plastic with the texture, you use the one master made of metal to stamp out multiple pieces. Thus, whatever features are in your master are replicated in the special plastic. Once we create that texture, if you put a drop of water on the texture, the water rolls down and doesn't stick to it, just like a lotus leaf. We have created a human-made structure that repels water, just like the lotus leaf."
The process of making the metal with the special texture works like this: the scientists take high-powered lasers, with energy beams 20 million times higher than that of a laser pointer, for example, and focus the beams on a metal surface. The metal absorbs the laser light and heats to a melting temperature of about 1200 degrees Centigrade, or higher, a process that rearranges the surface material to form a microtexture.
"All of this happens in less than 0.1 millionth of a second," Gupta says. "The microtexture is self-organized. By scanning the focused laser beam, we achieve a large area of microtexture. The produced microtexture is used as a stamper to replicate microtexture in polymers. The stamper can be used many, many times, allowing a low cost manufacturing process. The generated microtextured polymer surface shows very high water repellency."
In the fall of 2011, Gupta was among the first group of scientists to receive a $50,000 NSF Innovation Corps (I-Corps) award, which supports a set of activities and programs that prepare scientists and engineers to extend their focus beyond the laboratory into the commercial world.
Such results may be translated through I-Corps into technologies with near-term benefits for the economy and society. It is a public-private partnership program that teaches grantees to identify valuable product opportunities that can emerge from academic research, and offers entrepreneurship training to faculty and student participants.
The other project members are Paul Caffrey, a doctoral candidate under Gupta's supervision, and Martin Skelly of Charleston, S.C., a veteran of banking in the former Soviet Union who serves as business mentor and is involved in new business investments.
The team participated in a three-day entrepreneurship workshop at Stanford University run by entrepreneurs from Silicon Valley. "We are still pursuing the commercial potential," Gupta says. "The idea is to look at what market can use this technology, how big the market is, and how long it will take to get into it."
-- Marlene Cimons, National Science Foundation
Inspired by nature: textured materials to aid industry and military
Innovation Corps team developed metals and plastic that repel water, capture sunlight and prevent ice build-up
The lotus leaf has a unique microscopic texture and wax-like coating that enables it to easily repel water. Taking his inspiration from nature, a University of Virginia professor has figured out a way to make metals and plastics that can do virtually the same thing.
Mool Gupta, Langley Distinguished Professor in the university's department of electrical and computer engineering, and director of the National Science Foundation's (NSF) Industry/University Cooperative Research Center for Lasers and Plasmas, has developed a method using high-powered lasers and nanotechnology to create a similar texture that repels water, captures sunlight and prevents the buildup of ice.
These textured materials can be used over large areas and potentially could have important applications in products where ice poses a danger, for example, in aviation, the automobile industry, the military, in protecting communication towers, blades that generate wind energy, bridges, roofs, ships, satellite dishes, and even snowboards.
In commercial and military aviation, for example, these materials could improve airline safety by making current de-icing procedures, which include scraping and applying chemicals, such as glycol, to the wings, unnecessary.
For residents in the frigid northeast, many of whom rely on satellite systems, "it could mean they won't lose their signal, and they won't have to go outside with a hammer and chisel and break off the ice," Gupta says.
The materials' ability to trap sunlight also could enhance the performance of solar cells.
Gupta and his research team first made a piece of textured metal that serves as a mold to mass-produce many pieces of plastic with the same micro-texture. The replication process is similar to the one used in manufacturing compact discs. The difference, of course, is that the CD master mold contains specific information, like a voice, whereas, "in our case we are not writing any information, we are creating a micro-texture," Gupta says.
"You create one piece of metal that has the texture," Gupta adds. "For multiple pieces of plastic with the texture, you use the one master made of metal to stamp out multiple pieces. Thus, whatever features are in your master are replicated in the special plastic. Once we create that texture, if you put a drop of water on the texture, the water rolls down and doesn't stick to it, just like a lotus leaf. We have created a human-made structure that repels water, just like the lotus leaf."
The process of making the metal with the special texture works like this: the scientists take high-powered lasers, with energy beams 20 million times higher than that of a laser pointer, for example, and focus the beams on a metal surface. The metal absorbs the laser light and heats to a melting temperature of about 1200 degrees Centigrade, or higher, a process that rearranges the surface material to form a microtexture.
"All of this happens in less than 0.1 millionth of a second," Gupta says. "The microtexture is self-organized. By scanning the focused laser beam, we achieve a large area of microtexture. The produced microtexture is used as a stamper to replicate microtexture in polymers. The stamper can be used many, many times, allowing a low cost manufacturing process. The generated microtextured polymer surface shows very high water repellency."
In the fall of 2011, Gupta was among the first group of scientists to receive a $50,000 NSF Innovation Corps (I-Corps) award, which supports a set of activities and programs that prepare scientists and engineers to extend their focus beyond the laboratory into the commercial world.
Such results may be translated through I-Corps into technologies with near-term benefits for the economy and society. It is a public-private partnership program that teaches grantees to identify valuable product opportunities that can emerge from academic research, and offers entrepreneurship training to faculty and student participants.
The other project members are Paul Caffrey, a doctoral candidate under Gupta's supervision, and Martin Skelly of Charleston, S.C., a veteran of banking in the former Soviet Union who serves as business mentor and is involved in new business investments.
The team participated in a three-day entrepreneurship workshop at Stanford University run by entrepreneurs from Silicon Valley. "We are still pursuing the commercial potential," Gupta says. "The idea is to look at what market can use this technology, how big the market is, and how long it will take to get into it."
-- Marlene Cimons, National Science Foundation
Sunday, May 27, 2012
RESEARCHER TO HELP DEVELOP USES FOR NEW MATERIALS
FROM: U.S. DEPARTMENT OF DEFENSE ARMED WITH SCIENCE
ONR Researcher Tapped For Role In National Materials Genome Initiative
Written on MAY 26, 2012 AT 7:31 AM by JTOZER
The White House Office of Science and Technology Policy (OSTP) has selected an Office of Naval Research (ONR) director to serve as co-deputy chair of an interagency subcommittee tasked with speeding the advancement of new materials.
Dr. Julie Christodoulou, division director of naval materials in ONR’s Sea Warfare and Weapons department, became one of three co-deputy chairs of the National Science and Technology Council’s Subcommittee for the Materials Genome Initiative. The subcommittee is supporting the Materials Genome Initiative for Global Competitiveness (MGI), part of President Obama’s plan to accelerate the standard decades-long process to discover, mature and manufacture new materials.
Just as the Human Genome Project rejuvenated and spurred the growth of biological sciences by decoding the fundamental building blocks of human genetics, MGI is a national effort to build a materials innovation infrastructure that will accelerate the discovery and incorporation of materials in half the time and at a reduced cost of traditional approaches.
It took nearly 40 years for lithium-ion batteries to go from material discovery and development to mass market consumption.
With investment in the MGI, officials aim to gain efficiency in the scientific discovery process and accelerate commercial adaptation. Scientists supporting the initiative will advance computational tools that encourage collaboration throughout the development, certification, implementation and manufacturing processes of new materials, which will also shorten the transition time into commercial products.
“The purpose is to advance our experimental and computational tools, and to establish data-sharing protocols and ways of working together,” said Christodoulou. “That’s what all of this is about—trying to seed that infrastructure so that people have a way to work in this collaborative environment, which we believe is really going to make a difference in the world of materials science.”
Christodoulou will help oversee the effort with her co-deputy chairs, Dr. Charles Ward of the Air Force Research Laboratory and Dr. Ian Robertson of the National Science Foundation (NSF).
Dr. Cyrus Wadia, who is OSTP’s assistant director for clean energy and materials research and development, is the subcommittee chairman.
Federal agencies participating in the initiative include the departments of energy, commerce and defense; the National Institute of Standards and Technology; NSF; and NASA.
ONR has been at the forefront of funding basic research to help scientists discover, improve and incorporate new materials. The MGI will assist in focusing national attention, allowing the collective harnessing of similar but disparate interests, ultimately leading to more rapid advancement of materials for national security needs.
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