(Chem) Flavor and Spices: The Sweet Smell Of Nano-success
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#1: (Chem) Flavor and Spices: The Sweet Smell Of Nano-success Author: adediosLocation: Angel C. de Dios PostPosted: Mon Jan 30, 2006 7:00 am
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Source: Lehigh University
Date: 2006-01-30
URL: http://www.sciencedaily.com/re.....031726.htm

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The Sweet Smell Of Nano-success:Cleaner Method Of Making Spices, Perfumes Moves One Step Closer To Reality

Materials scientists at Lehigh University and catalyst chemists at Cardiff University have uncovered secrets of the "nanoworld" that promise to lead to cleaner methods of producing, among other things, spices and perfumes.

The materials scientists, headed by Christopher Kiely of Lehigh, have determined the structure of a type of gold-palladium nanoparticle, which is the active component of a new environmentally friendly catalyst that promotes the oxidation of primary alcohols to aldehydes.

The researchers reported their results Jan. 20 in Science magazine, one of the world's top science journals. The article was titled "Solvent-free oxidation of primary alcohols to aldehydes using titania-supported gold-palladium catalysts."

The oxidation of primary alcohols to aldehydes is of fundamental importance to the chemical, pharmaceutical and perfume industries.

The oxidation of aromatic primary alcohols, such as vanillyl and cinnamyl alcohol, is of particular importance in the manufacture of perfumes and flavorings. Almost 95 percent of the worlds' vanilla (vanillyl aldehyde) is synthetically manufactured.

Benzaldehyde is also a key intermediate in the production of many fine chemicals in the agrochemical and pharmaceutical industries.

Such oxidation reactions have always been performed using permanganates or chromates, but these reagents are expensive and have serious toxicity issues associated with them. This new catalyst, consisting of gold-palladium nanoparticles dispersed on a titanium oxide support, allows this reaction to take place using oxygen under mild solvent-free conditions.

The new catalyst system was developed by a group headed by Prof. Graham Hutchings at Cardiff University in the United Kingdom.

"Determining the structure of the gold-palladium nanoparticle will help us understand how this catalyst works at the atomic level," says Kiely, who directs the Nanocharacterization Laboratory at Lehigh University in Bethlehem, Pa.

"This will inevitably enable us to optimize its performance and will subsequently lead to the development of other gold-based catalysts."

Samples of the catalyst were studied by Andrew Herzing, a Ph.D. candidate in materials science and engineering in Lehigh's Center for Advanced Materials and Nanotechnology (CAMN). Herzing used Lehigh's VG HB 603 aberration-corrected scanning transmission electron microscope (STEM), which enables energy dispersive x-ray data to be collected from individual nanoparticles.

"Our aberration-corrected STEM is unique in that it has an extremely small and intense electron probe. It also has a very high collection efficiency for the x-rays generated," says Kiely.

The original microscope was purchased almost a decade ago but was fitted only last year with a spherical aberration corrector designed to overcome distortions in the lenses that focus the electron beam. This has led to a significant improvement in resolution.

"Before being fitted with the aberration corrector, this microscope held the world record for spatial resolution in x-ray elemental mapping at two nanometers (two billionths of a meter)," says Kiely.

"Now, with the aberration corrector, it achieves an elemental mapping resolution of half a nanometer, approximately the width of two atoms."

Even so, obtaining chemical information from the tiny gold-palladium particle is difficult because the x-ray signal from a palladium atom is far weaker than the signal from a gold atom. There are also signals from the titanium oxide support. Under normal circumstances, the palladium signal would be lost in the noise.

To overcome this, Masashi Watanabe, a research scientist in the CAMN, has developed software based on multivariate statistical analysis combined with a spectrum imaging technique. While scanning for a particular element, Watanabe's software compares all the signals generated from an area and automatically identifies features in a particular signal dataset (in this case, a characteristic palladium X-ray signal).

Watanabe's automated approach significantly reduces the amount of random noise both in the signal and background. While a similar methodology has been in use for some time, Watanabe's program reduces the data analysis time from several hours to a few minutes.

Elemental maps collected from individual nanoparticles revealed that the palladium signal originates from a slightly larger spatial area than that of the corresponding gold signal. From this, Kiely's team concluded that the nanoparticles have a core-shell structure in which a palladium-rich shell surrounds a gold-rich core.

Even though the outer shell is palladium rich, this gold-palladium catalyst significantly outperformed a similar catalyst comprised solely of palladium. It is proposed that the gold acts as an electron promoter for the palladium, thus enhancing the nanoparticle's catalytic properties.

"Correlating a particular catalyst's performance with detailed structural and compositional data consistently proves to be a powerful methodology for understanding catalytic reactions," says Kiely.

Kiely has been collaborating with Hutchings for more than 10 years. The Lehigh-Cardiff team published an article titled "Tuneable gold catalysts for selective hydrocarbon oxidation under mild conditions" in Nature magazine on Oct. 20.

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Questions to explore further this topic:

What are alcohols?

http://www.chemguide.co.uk/org.....round.html

What are aldehydes?

http://www.chemguide.co.uk/org.....round.html

What are some examples of molecules that add spice and flavor?

http://antoine.frostburg.edu/c.....icin.shtml
http://wwwchem.uwimona.edu.jm/lectures/spices.html

How big is the vanilla economy?

http://www.iff.com/Internet.ns.....AA006D3617

How big is the flavor industry?

http://courses.che.umn.edu/03f.....dustry.htm

What is flavor chemistry?

http://pubs.acs.org/subscribe/.....esney.html
http://class.fst.ohio-state.edu/fst820/820-1.pdf

Here is a "spice" encyclopedia

http://www.spiceadvice.com/encyclopedia/index.html

A short history on spice

http://www.spiceadvice.com/history/index.html

The chemistry of "delicious"

http://www.foodnavigator-usa.c.....p?id=64656

An excerpt from the book "What Einstein Told His Cook"

http://www.wwnorton.com/catalo.....xcerpt.htm

What are some of the challenges in "Flavors and Spices" chemistry?

http://pubs.acs.org/hotartcl/c...../flav.html

What is food science and technology?

http://www.foodscience.psu.edu.....plore.html
http://www.ift.org/cms/?pid=1000411


************Second Part: Nanoscience and Nanotechnology**************

How small is a nano-?

http://cohesion.rice.edu/natur.....oc_id=3057
http://www.vendian.org/howbig/cube/
http://www.vendian.org/howbig/.....izona_fire

The Powers of Ten: Cosmic View in 40 Jumps

http://www.vendian.org/mncharity/cosmicview/

Here are some of the current workers in the field of nanotechnology

http://cohesion.rice.edu/Natur.....forWeb.htm
http://mrsec.wisc.edu/Edetc/te.....index.html

To understand "nano-", we need to go back to atoms and molecules

http://cohesion.rice.edu/Natur.....forWeb.htm

What are single molecules?

http://cohesion.rice.edu/natur.....oc_id=3134

What is chemical bonding?

http://cohesion.rice.edu/Natur.....forWeb.htm

You could join the NanoScholars' Club at Rice University

http://cohesion.rice.edu/natur.....Join_1.cfm

What is nanoscience?

http://www.newhorizons.org/str...../allen.htm
http://www.uc.edu/news/NR.asp?id=3173

How do we see such small things?

http://www.nnin.org/nnin_seeing.html

Nanotechnology : a Talk from Rice University

http://nsfmli.rice.edu/present.....20Talk.pdf

Potential Uses of Nanotechnology

http://www.nims.go.jp/ws-nanon.....SF-USr.pdf

Learning modules for nanotechnology

http://mrsec.wisc.edu/Edetc/modules/index.html

Nanoscale activities

http://mrsec.wisc.edu/Edetc/IP.....index.html

Nano - Movies

http://mrsec.wisc.edu/Edetc/cineplex/index.html

Background information regarding some nanomaterials

http://mrsec.wisc.edu/Edetc/materials/index.html

Slideshows for materials

http://mrsec.wisc.edu/Edetc/SlideShow/index.html

Virtual Tour of NanoWorld Discovery Exhibit

http://mrsec.wisc.edu/Edetc/ci.....index.html

Nanotechnology in News

http://mrsec.wisc.edu/Edetc/cineplex/nanotech.html
http://mrsec.wisc.edu/Edetc/cineplex/live5.html

History of nanoscience and nanotechnology

http://www.discovernano.northwestern.edu/

Videos on new materials

http://www.materialsworldmodul.....iption.htm

Resources that can accompany the above videos

http://www.materialsworldmodul.....ces/im.htm

GAMES

http://pbskids.org/zoom/games/kitchenchemistry/
http://chemistry.about.com/lib.....40103a.htm


Last edited by adedios on Sat Jan 27, 2007 4:09 pm; edited 2 times in total

#2: Titania Nanotubes Create Potentially Efficient Solar Cells Author: adediosLocation: Angel C. de Dios PostPosted: Tue Feb 14, 2006 7:18 pm
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Source: Penn State

Posted: February 14, 2006

Titania Nanotubes Create Potentially Efficient Solar Cells

A solar cell, made of titania nanotubes and natural dye, may be the answer to making solar electricity production cost-effective, according to a Penn State researcher.

"Solar cell technology has not changed very much over time and is still predominantly silicon solar cells," says Dr. Craig Grimes, professor of electrical engineering and materials science and engineering. "It takes a great deal of energy, 5 gigajoules per square meter, to make silicon solar cells. It can be argued that silicon solar cells never fully recover the energy it takes to make them in the first place."

The new focus in solar cells is toward dye sensitive solar cells, which have been made using nanoparticles and a variety of dyes.

"Nanoparticle solar cells are the gold standard of this new approach," says Grimes. "However, because of limitations, it appears they have gotten as good as they are going to get."

The researchers are instead looking at titania nanotubes to replace the particulate coatings in dye sensitive solar cells and, their initial attempt produced about 3 percent conversion of solar energy to electricity, they report in today's issue of Nano Letters. The researcher's inability to grow longer titania nanotubes, constrained the solar conversion rate.

"I think we can reach a 15 percent conversion rate with these cells, and other researchers do as well," says Grimes. "That is 15 percent with a relatively easy fabrication system that is commercially viable."

Conventional solar cells are made from blocks of slowly made silicon boules that are sliced into wafers. Grimes and his team use an easier approach. They coat a piece of glass with a fluorine-doped tin oxide and then sputter on a layer of titanium. The researchers can currently lay down a 500-nanometer thick titanium layer. They then anodize the layer by placing it in an acidic bath with a mild electric current and titanium dioxide nanotube arrays grow to about 360 nanometers. The tubes are then heated in oxygen so that they crystalize. The process turns the opaque coating of titanium into a transparent coating of nanotubes.

This nanotube array is then coated in a commercially available dye. The dye-coated nanotubes make up the negative electrode and a positive electrode seals the cell which contains an iodized electrolyte. When sun shines through the glass, the energy falls on the dye molecules and an electron is freed. If this electron and others make their way out of the tube to the negative electrode, a current flows. Many electrons do not and are recombined, but the tube structure of the titanium dioxide allows an order of magnitude more electrons to make it to the electrode than with particulate coatings.

"There is still a great deal of optimization of the design that needs to be done," says Grimes. "Now, with the help of the Pennsylvania Energy Development Authority, we will have equipment to make high quality titanium coatings that are thicker. If we get about 3 percent conversion with 360 nanometers, what we could get with 4 microns is an exciting question we soon hope to answer."

The thickness of the titanium layer constrains the height of the nanotubes. With thicker initial coatings, longer tubes would produce more electrons that do not recombine, producing more electricity.

Other aspects of the titania nanotube dye sensitive solar cells that need to be optimized include the thickness of the cells. Currently, spacers separate the two layers and provide internal support. These spacers are 25 microns thick. If the spacers could be made as sturdy, but shorter, there would be less of a distance for the electrons to travel and more electrons will make it across the electrodes.



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Grimes team includes Dr. Gopal K. Mor, Dr. Maggie Paulose and Dr. Oomman K. Varghese, postdoctoral researchers in Penn State's Materials Research Institute, and Karthik Shankar, graduate student in electrical engineering. The National Science Foundation supported this work and a recent grant from the U.S. Department of Energy will help optimize the solar cells.

#3: Manufactured Nanoparticles Might Pose Health Threat Author: adediosLocation: Angel C. de Dios PostPosted: Mon Mar 06, 2006 4:12 pm
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Manufactured Nanoparticles Might Pose Health Threat
By Scott Fields
Special to LiveScience
posted: 06 March 2006
09:03 am ET

Buckyballs, among the most used and certainly the most celebrated of manmade nanoparticles, might represent a potent health threat.

According to computer simulations the 60-carbon-atom, soccer-ball-shaped molecule can damage or even destroy DNA.

Researchers have suggested that buckyballs, whose technical name is "fullerenes," might be used in chemical sensors and hydrogen fuel cells. And some researchers are testing biomedical applications in which buckyballs would encapsulate especially toxic drugs or radioactive materials.

Scientists already realized buckyballs could be toxic. Studies at Duke University in 2004 showed that when buckyballs were introduced to laboratory aquariums they damaged the brains of largemouth bass and may also have prevented certain water-borne bacteria from reproducing.

Until then scientists had theorized that the strong attraction that buckyballs have for each other would cause the molecules to clump together and safely sink to the bottom of any body of water, be it a test aquarium or a lake.

As it turns out, says Peter Cummings, a professor of chemical engineering at Vanderbilt University and director of the Oak Ridge National Laboratory's Nanomaterials Theory Institute, in water the attraction between a buckyball molecule and a DNA molecule is several times stronger than the attraction between two buckyballs.

"We found, somewhat surprisingly, that these buckyballs bond quite strongly to both double-stranded and single-stranded DNA," said Cummings, whose group designed the simulation. "They bond strongly enough that they distort the structure of the DNA."

The buckyballs break apart vital hydrogen bonds within the DNA molecule's double helix and they can stick to grooves on DNA's surface, causing the molecule to bend. Not only do the buckyballs damage the DNA, Cummings says, they cripple its ability to heal.

"The buckyballs insert themselves in a way that prevents the DNA from self-repairing," Cummings told LiveScience. The buckyball actually forces a piece of nucleotide from one of the DNA's double helixes and takes its place, preventing the strands from reuniting.

Cummings cautions that this simulation work didn't test whether buckyballs can breach the cell walls that house DNA molecules. That would require another simulation project and, eventually, laboratory tests on living organisms. And, he notes, these results don't mean that all nano-scale building blocks pose such threats.

#4: Body Movement Generates Electricity in Miniature Device Author: adediosLocation: Angel C. de Dios PostPosted: Thu Apr 13, 2006 7:10 pm
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Body Movement Generates Electricity in Miniature Device
By Ker Than
LiveScience Staff Writer
posted: 13 April 2006
02:01 pm ET



A new class of devices aims to convert energy created from body movement, the stretching of muscles or the flow of water to power future nanoscale components.

These so-called "nanogenerators" would be less bulky than traditional energy sources such as batteries.

Zhong Lin Wang of the Georgia Institute of Technology and graduate student Jinhui Song have created a prototype nanogenerator that produces electrical current through the bending and relaxing of zinc oxide nanowires.

When the nanowires flex, they emit a piezoelectric discharge, which is electricity generated by certain materials under mechanical stress.

A nanometer is one billionth of a meter; a human hair is roughly 100,000 nanometers wide.

Because zinc oxide is non-toxic, the new nanogenerator could be implanted safely into the body.

"Our bodies are good at converting chemical energy from glucose into the mechanical energy of our muscles," Wang said. "These nanogenerators can take that mechanical energy and convert it to electrical energy for powering devices inside the body."

Wang thinks such devices could be used wherever mechanical energy is available. The hydraulic motion of seawater would work, or the motion of a foot inside a shoe.

"You could envision having these nanogenerators in your shoes to produce electricity as you walk," Wang said. "This could be beneficial for soldiers in the field, who now depend on batteries to power their electrical equipment. As long as the soldiers were moving, they could generate electricity."

The device is detailed in the March 14 issue of the journal Science.

#5: Growing glowing nanowires to light up the nanoworld Author: adediosLocation: Angel C. de Dios PostPosted: Thu May 25, 2006 3:35 pm
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http://www.eurekalert.org/pub_.....052506.php

National Institute of Standards and Technology (NIST)
25 May 2006

Growing glowing nanowires to light up the nanoworld


The nano world is getting brighter. Nanowires made of semiconductor materials are being used to make prototype lasers and light-emitting diodes with emission apertures roughly 100 nm in diameter--about 50 times narrower than conventional counterparts. Nanolight sources may have many applications, including "lab on a chip" devices for identifying chemicals and biological agents, scanning-probe microscope tips for imaging objects smaller than is currently possible, or ultra-precise tools for laser surgery and electronics manufacturing.
Researchers at the National Institute of Standards and Technology (NIST) are growing nanowires made of gallium nitride alloys and making prototype devices and nanometrology tools. The wires are grown under high vacuum by depositing atoms layer by layer on a silicon crystal. NIST is one of few laboratories capable of growing such semiconductor nanowires without using metal catalysts, an approach believed to enhance luminescence and flexibility in crystal design. The wires are generally between 30 and 500 nanometers (nm) in diameter and up to 12 micrometers long. When excited with a laser or electric current, the wires emit an intense glow in the ultraviolet or visible parts of the spectrum, depending on the alloy composition.

A paper in the May 22 issue of Applied Physics Letters* reports that individual nanowires grown at NIST produce sufficiently intense light to enable reliable room-temperature measurements of their important characteristics. For example, the peak wavelength of light emitted with electric field parallel to the long axis of a nanowire is shifted with respect to the peak wavelength emitted with electric field perpendicular to the wire. Such differences in emission are used to characterize the nanowire materials and also may be exploited to make sensors and other devices.

NIST has grown a variety of nanowires and extensively characterized their structural and optical properties, finding few defects, strains or impurities, which results in high light output compared to the bulk material.** The wires also can be transferred from the silicon crystal to other substrates, such as sapphire, and arranged using electric fields. The NIST team has used the nanowires to make a number of prototype devices, including light-emitting diodes, field-effect transistors, and nanowire "bridge" structures that may be useful in sensors and nanoscale mechanical resonators.


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*J.B. Schlager, N.A. Sanford, K.A. Bertness, J.M. Barker, A. Roshko and P.T. Blanchard. 2006. Polarization-resolved photoluminescence study of individual GaN nanowires grown by catalyst-free MBE. Applied Physics Letters. May 22.
** K.A. Bertness, N.A. Sanford, J.M. Barker, J.B. Schlager, A. Roshko, A.V. Davydov and I. Levin. 2006. Catalyst-Free Growth of GaN Nanowires. Journal of Electronic Materials 35, 576. April.

#6: Triple threat polymer captures and releases Author: adediosLocation: Angel C. de Dios PostPosted: Mon Jun 12, 2006 11:49 am
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Triple threat polymer captures and releases

The perfect host

By Tony Fitzpatrick


June 8, 2006 -- A chemist at Washington University in St. Louis has developed a remarkable nanostructured material that can repel pests, sweeten the air, and some day might even be used as a timed drug delivery system — as a nasal spray, for instance.

Karen L. Wooley, Ph.D., Washington University James S. McDonnell Distinguished University Professor in Arts & Sciences, has taken the same materials that she developed more than four years ago as marine "antifouling" coatings that inhibit marine organisms such as barnacles from attaching to ship hulls to now capture fragrance molecules and release them at room temperature.

Wooley mixes two normally incompatible polymers — a hyperbranched fluoropolymer and a linear polyethylene glycol — and lets them phase-separate into distinct domains, one interspersed in the other. A chemical process called crosslinking then solidifies the mixture, thus creating a heterogeneous coating that, upon close examination, reveals treacherous nanometer-sized terrain composed of mountains and valleys, ranging from hard to soft, hydrophilic to hydrophobic. The complex surface that is created makes it difficult for marine organisms to establish a toehold. Her laboratory has produced these novel materials and they are being used around the world

Wooley and her collaborators were intrigued by the surface of these nanostructured materials and began to wonder what was beneath the surface. They found that their materials made a perfect host to serve guest molecules.

"We looked at the roughness and complexity of the surface and thought that the surface might provide interesting entrance and exit ports for small molecule guests," Wooley explained. "So, our material would be a host that would act like a sponge, because we have this complex subsurface morphology, and we thought of it as being domains that might be like holes in sponges and other domains that might be like sponge material."

Be my guest

The subsurface composition and properties might thereby allow the guests to partition off into one domain and then another guest partition into another domain.

"We have these channels to serve as capillaries to take in guest molecules and hold them inside the material," said Wooley, a member of Washington University's Center for Materials Innovation, (CMI) which enables collaborators from across the Washington University campus to make basic and applied advances in materials research, touching many aspects of daily life.

She and her group received a research grant from Imperial Chemical Industries/National Starch to continue their study, with a goal of taking the guest molecules in and holding them. Using the technology of thermogravimetric analysis (TGA), Gerald O. Brown, Ph.D., a postdoctoral research associate in Wooley's group, began analyzing the release of these guests — fragrance molecules — as gaseous small molecules from the polymer across the network of the host material.

"We found that the temperatures at which the guests left the material were dependent on the composition of the host, and when the release of the small guest molecules was monitored from just an empty TGA pan, there was a slight difference versus those guests in the presence of either the hyperbranched fluoropolymer or the polyethylene glycol," she said. "There is a slight depression of temperature at which the small molecule fragrance volatilizes and becomes a gas."

However, when they looked at the complex materials — the ones designed to be anti-fouling materials — they found a progression of decreasing temperature as they went with different amounts of poly (ethylene glycol) relative to hyperbranched fluoropolymer in the composite material.

"What's amazing is that there is a 55 degree temperature reduction at which this small molecule leaves the host material versus it leaving an empty pan," she said. "Then we thought that this material could be very useful as something to promote the release of a volatile agent — maybe for some kind of nasal inhalation-based delivery of drugs. Or maybe something as simple as a room-temperature release of a fragrance."

Sponge analogy

Wooley said that they don't know where the guest molecules are residing in the host material, and her group is now inserting stable isotopes into the host and guest molecules and with the help of her colleague Jacob Schaefer, Ph.D., Washington University Charles Allen Thomas Professor of Chemistry, will measure the difference between those stable isotopes to help find where the guests are located relative to the host.

"We want to know where they reside because that should tell us why this material is providing a favorable environment at room temperature but at elevated temperature for some reason everything is being expelled rapidly," she said. "We don't know if there is some reorganization of the morphology of the material or whether the guests partition to different domains at different temperatures."

Wooley says that the results of her research with the polymers — the promoted release, the anti-fouling application — are "strange, if not weird, but there is so much going on here, we want to explore it all."

That weirdness suggests equally weird mechanical properties. Wooley and her post doctoral researcher Jinqi Xu, Ph.D., are exploring those properties and one essential irony — the material, similar to a hydrogel because it takes in water, oddly becomes stronger when water absorbs into it. Think of a soggy diaper as a hydrogel. If you liken Wooley's materials to a diaper, that wet one becomes nearly petrified. That's known as an increased modulus value — a measure of stress versus strain.

"When you pull on a sponge, the water comes back out," she said. "But in our case, because our sponge and the channels within it are essentially nanoscopic, the water cannot get out, at least not fast enough to allow for a reorganization of the material, and therefore it just rigidifies the material."

Xu made a presentation on this research at the 2006 Spring Meeting of the American Chemical Society (ACS), held March 26-30 in Atlanta. Wooley and her collaborators published a communication on the research in the Journal of the American Chemical Society, 2005, 127, 11238-11239.

#7: Tiny inhaled particles take easy route from nose to brain Author: adediosLocation: Angel C. de Dios PostPosted: Thu Aug 03, 2006 7:31 am
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University of Rochester Medical Center
2 AUgust 2006

Tiny inhaled particles take easy route from nose to brain

In a continuing effort to find out if the tiniest airborne particles pose a health risk, University of Rochester Medical Center scientists showed that when rats breathe in nano-sized materials they follow a rapid and efficient pathway from the nasal cavity to several regions of the brain, according to a study in the August issue of Environmental Health Perspectives.

Researchers also saw changes in gene expression that could signal inflammation and a cellular stress response, but they do not know yet if a buildup of ultrafine particles causes brain damage, said lead author Alison Elder, Ph.D., research assistant professor of Environmental Medicine.

The study tested manganese oxide ultrafine particles at a concentration typically inhaled by factory welders. The manganese oxide particles were the same size as manufactured nanoparticles, which are controversial and being diligently investigated because they are the key ingredient in a growing industry -- despite concerns about their safety.

Nanotechnology is a new wave of science that deals with particles engineered from many materials such as carbon, zinc and gold, which are less than 100 nanometers in diameter. The manipulation of these materials into bundles or rods helps in the manufacturing of smaller-than-ever electronics, optical and medical equipment. The sub-microscopic particles are also used in consumer products such as toothpaste, lotions and some sunscreens.

Some doctors and scientists are concerned about what happens at the cellular level after exposure to the ultrafine or nano-sized particles, and the University of Rochester is at the forefront of this type of environmental health research. In 2004 the Defense Department selected the University Medical Center to lead a five-year, $5.5 million investigation into whether the chemical characteristics of nanoparticles determine how they will interact with or cause harm to animal and human cells.

In the current study, the particles passed quickly through the rats' nostrils to the olfactory bulb, a region of the brain near the nasal cavity. They settled in the striatum, frontal cortex, cerebellum, and lungs.

After 12 days, the concentration of ultrafine particles in the olfactory bulb rose 3.5-fold and doubled in the lungs, the study found. Although the ultra-tiny particles did not cause obvious lung inflammation, several biomarkers of inflammation and stress response, such as tumor necrosis factor and macrophage inflammatory protein, increased significantly in the brain, according to gene and protein analyses.

"We suggest that despite differences between human and rodent olfactory systems, this pathway is likely to be operative in humans," the authors conclude.


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The U.S. Environmental Protection Agency, National Institute of Environmental Health Sciences, Department of Defense and Department of Energy funded the study.

#8: Use of Nanotechnology as Diagnostic and Screening Tool Author: adediosLocation: Angel C. de Dios PostPosted: Mon Aug 14, 2006 2:55 pm
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August 14, 2006
Rush University Medical Center

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Rush Researchers Explore Use of Nanotechnology as Diagnostic and Screening Tool for Women’s Health

Early Detection of Ovarian Cancer is a Goal

(Chicago) – Nanotechnology is revolutionizing the way things are constructed -- from stain resistant clothing to stronger, yet lighter tennis rackets. However, the biggest impact of nanotechnology in the future is expected to be in the healthcare industry.

At Rush University Medical Center, researchers believe nanotechnology can lead to strikingly new ways to diagnosis and treat ovarian cancer. In a unique collaboration with Argonne National Laboratory and the Illinois Institute of Technology, Rush researchers are employing state-of-the-art nanotechnology to improve the health of women.

“While the mortality rates of many cancers have decreased significantly in recent decades, the rate for ovarian cancer had not changed much in the last 50 years, primarily due to delays in diagnosis,” said Dr. Jacob Rotmensch, section director of gynecologic oncology at Rush. “By exploiting the unique properties of nanotechnology, we hope to detect ovarian cancer earlier using highly sensitive imaging tools and develop drug carriers that can deliver therapeutic agents inside tumor cells.”

“A nanotechnology based approach is needed because diagnosis of early stage cancer requires the detection and characterization of very small quantities of biomarker” added Dr. Liaohai Chen, a molecular biologist and leader of the nano-bio group in the Biosciences Division at Argonne, and an adjunct faculty at Rush University Medical Center.

A nanometer is one billionth of a meter or 1/80,000 the width of a human hair. Nanoscale devices can perform tasks inside the body that would otherwise not be possible, such as entering most cells and moving through the walls of blood vessels. As a result, nanoscale devices can readily interact with individual molecules on both the cell surface and within the cell, in ways that do not alter the behavior of those molecules.

One area of research involves developing a screening test that would not require removal of the ovary for biopsy. Collaborating with Dr. Rong Wang, an associate professor at Illinois Institute of Technology, the research team is using an atomic force microscope, a very-high resolution microscope that can investigate the interaction of individual protein molecules. With this microscope the research team can study the molecular structure of cancer versus non-cancer cells and compare the stiffness. Cancer tissues are more stiff than healthy tissues. Instead of removing the ovary to determine if cancerous tissue is present, a probe is currently under development to follow the tissue stiffness in vivo to diagnose cancer.

A second area of research involving nanotechnology uses viral particles as templates to fabricate uniform, nanometer imaging probes and drug carriers. The research team is extracting the DNA from viral particles and replacing it with imaging agents. The goal is to have the viral capsule adhere to a cancer cell and inject the imaging or a therapeutic agent into the cell. This technology could lead to early diagnosis and the development of targeted drug therapy that kills cancer cells while leaving the rest of the body unharmed.

“The development of a smart probe and carrier complex will provide significant advantage to the clinicians as they can locate the tumor, monitor the drug delivery vehicle and control drug release using imaging techniques,” said Chen.

Another avenue of nanotechnology research at Rush is to develop nanometer sized contrast agents with ultrasound to diagnose ovarian cancer. Such nano ultrasonographic contrast media can pass through the smallest capillaries. These tiny bubbles light up on ultrasound and may be able to show the earliest vascular changes associated with ovarian malignancy. If this is successful, further research will be conducted to study targeted imaging as well as targeted therapy.

Ovarian cancer is the fifth-most common cancer among American women and claims the lives of more North American women each year than all other gynecologic malignancies combined. About 75 percent of patients are not diagnosed until the disease is in its later stages, and current therapies are not effective enough to successfully treat the disease in such advanced stages.

“There has been a great amount of progress made in the field of nanotechnology over the last five years, but it has not yet been applied to women’s health,” said Rotmensch. “We believe this ‘small-particle’ technology has the capability to quickly and sensitively detect cancer molecules earlier than ever before. This research opens new avenues that will directly impact patient care, such as drug development, diagnostic imaging and ultimately, prevention.”

These nanotechnology research projects are collaboration among Rush University Medical Center, Argonne National Laboratory, and the Illinois Institute of Technology under the directorships of Dr. Jacob Rotmensch and Dr. Liaohai Chen. The collaboration promotes the education, dialogue, and interaction of physicians and biologists with chemists, physicists and engineers to foster the research of applying nanotechnology to gyn-oncology and regenerative medicine. One goal of the research is to develop novel medical imaging and a drug delivery vehicle that will drive state-of-the-art screening, treatment and prevention of women’s disease to a new level.

#9: Atomic Drive Author: adediosLocation: Angel C. de Dios PostPosted: Sat Aug 19, 2006 8:23 am
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Atomic Drive

23 August 2006
Emily Sohn

Trucks, tractors, and bulldozers are impressive machines. They can rip into the earth or carry tons of gear. Large vans line the streets of many neighborhoods in the United States. Meanwhile, everyday automobiles seem to be getting bigger and bigger.
A new wave of vehicles, however, is pushing a different kind of size limit. Called nanocars, these dream machines are practically invisible.

For the full article (photos and additional links):

http://www.sciencenewsforkids......ature1.asp
http://www.sciencenewsforkids......3/refs.asp
http://www.sciencenewsforkids......ksheet.asp

#10: Magnetic, Luminescent Nanoparticles Set New Standard Author: adediosLocation: Angel C. de Dios PostPosted: Thu Jan 25, 2007 3:41 pm
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Magnetic, Luminescent Nanoparticles Set New Standard
January 25th, 2007 @ 12:13 pm by Andy (UC Davis)

Researchers at UC Davis have created a new type of nanoparticles that could be used in tests for environmental pollution or contamination of food products, and for medical diagnostics.

The particles, about 100 to 200 nanometers in size, are luminescent, magnetic and inexpensive to make, and can be tagged with antibodies. They are made up of a magnetic core of iron oxide or iron/neodymium/cobalt oxide coated in a shell of europium and gadolinium oxide. When stimulated with a laser, europium emits red light at a very specific wavelength.

The nanoparticles can be manipulated with magnets and detected by fluorescence. They could also be labeled with other fluorescent labels in different colors, or used as part of an assay with other fluorescent labels. The built-in europium luminescence acts as an internal standard, making it easier to carry out accurate quantitative assays, said Ian Kennedy, professor of mechanical and aeronautical engineering and senior author on a paper describing the work.

The particles can also be coated with short pieces of DNA and used for genetic analysis. The team is exploring uses including testing for bioterrorism agents such as ricin or botulinum toxin in food and for genetic tests in cancer medicine.

The nanoparticles were made by spray pyrolysis, which involves mixing the raw material in a solvent and spraying it through a flame. The method is much cheaper than the techniques previously used for making similar particles, and can readily be scaled up to industrial production. It is already used in the chemical industry to make products such as fumed silica and carbon black.

Other authors on the paper are research specialist Dosi Dosev, Department of Mechanical and Aeronautical Engineering; postdoctoral researcher Mikaela Nichkova, research associate Shirley Gee and Professor Bruce Hammock, all of the Department of Entomology; and physics graduate student Randy Dumas and Kai Liu, associate professor of physics.

The researchers are establishing a company, Synthia LLC, to develop the technology further.

The paper is published online in the journal Nanotechnology and will appear in the Feb. 7, 2007, print issue of the journal. The work was funded primarily by the National Science Foundation and the Superfund Basic Research Program of the National Institute of Environmental Health Sciences.

http://fanon.engr.ucdavis.edu/.....earch.html
http://www.iop.org/EJ/abstract.....8/5/055102

#11: Ancient Crumbs Reveal History of Chili Peppers Author: adediosLocation: Angel C. de Dios PostPosted: Fri Feb 16, 2007 7:46 am
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Ancient Crumbs Reveal History of Chili Peppers

By Jeanna Bryner
LiveScience Staff Writer
posted: 15 February 2007
02:02 pm ET

Dried-up bits of food lurking on dinnerware make diners cringe, but they are like gold for an archaeo-botanist.

Hot on a new trail of microscopic crumbs, researchers led by Linda Perry of Smithsonian’s National Museum of Natural History have revealed that domesticated chili peppers originated in the Americas earlier than previously thought, even before people started making pottery.

Until now, scientists had a hazy and disjointed record of the spread of domesticated chili peppers (Capsicum)—considered one of the most prevalent of the plants cultivated in the Americas.

The food residues were found on 6,000-year-old cooking utensils unearthed from various sites in Central and South America.

For the full article:

http://www.livescience.com/his....._find.html

#12: A new process for making much-sought iron nanospheres Author: adediosLocation: Angel C. de Dios PostPosted: Mon Feb 19, 2007 9:47 am
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A new process for making much-sought iron nanospheres
Journal of the American Chemical Society
19 February 2007

Using a process that creates bubbles as hot as the surface of the sun, chemists are reporting development of a new method for making hollow hematite (iron oxide) nanospheres. The University of Illinois at Urbana-Champaign's Kenneth S. Suslick and Jin Ho Bang describe the synthesis of these iron nanoparticles in a report scheduled for the Feb. 28 issue of the Journal of the American Chemical Society, a weekly publication.

Hollow nanospheres of metals and other inorganic materials are generating great interest because of their unusual properties and potential applications in drug delivery, electronic components, catalysts and other products. "We believe that this procedure will be easily extended to prepare other hollow inorganic materials," the researchers note. In the past, production of hollow hematite nanospheres required a time-consuming process and use of toxic hydrofluoric acid.

The new process uses sonochemistry, in which high-frequency sound waves are focused into a solution containing an iron compound and carbon nanoparticles. Those sound waves create tiny bubbles in the liquid. The collapse of those bubbles causes intense local heating with temperatures estimated at 9,000 F, which is nearly as hot as the surface of the sun. The sonochemical process forms iron spheres around the carbon nanoparticles. On exposure to air, the iron rapidly oxidizes, which burns away the carbon core, leaving hematite spheres one thousandth the diameter of a red blood cell.

ARTICLE #2 FOR IMMEDIATE RELEASE
"Sonochemical Synthesis of Nanosized Hollow Hematite"

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http://pubs.acs.org/cgi-bin/sa.....676657.pdf


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http://pubs.acs.org/cgi-bin/sa.....76657.html

#13: UC Researchers Shatter World Records with Length of Latest C Author: adediosLocation: Angel C. de Dios PostPosted: Wed Apr 25, 2007 5:45 pm
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UC Researchers Shatter World Records with Length of Latest Carbon Nanotube Arrays

Date: 4/25/2007
By: Wendy Beckman


UC engineering researchers have developed a novel composite catalyst and optimal synthesis conditions for oriented growth of multi-wall CNT arrays. And right now they lead the world in synthesis of extremely long aligned carbon nanotube arrays.


Carbon nanotubes (CNTs) are of great interest because of their outstanding mechanical, electrical and optical properties. Intense research has been undertaken to synthesize long aligned CNTs because of their potential applications in nanomedicine, aerospace, electronics and many other areas.

For the full article:

http://www.uc.edu/news/NR.asp?id=5700

#14: Nanotechnology provides 'green' path to environmentally sust Author: adediosLocation: Angel C. de Dios PostPosted: Thu Apr 26, 2007 11:09 am
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Project on Emerging Nanotechnologies
26 April 2007

Nanotechnology provides 'green' path to environmentally sustainable economy

WASHINGTON, DC – As products made with nanometer-scale materials and devices spread to more industries and markets, there is a growing opportunity and responsibility to leverage nanotechnology to reduce pollution, conserve resources and, ultimately, build a "clean" economy, advises a new report from the Project on Emerging Nanotechnologies.

A "strong marriage" between nanotechnology and the principles and practices of green chemistry and green engineering "holds the key to building an environmentally sustainable society in the 21st century," concludes Green Nanotechnology: It's Easier Than You Think. Summarizing proceedings at a national American Chemical Society symposium and four workshops held in 2006, the new report was authored by science writer Karen Schmidt for the Project on Emerging Nanotechnologies, an initiative of the Woodrow Wilson International Center for Scholars and The Pew Charitable Trusts.

The report explores potentially beneficial links between nanotechnology – essentially, science and engineering practiced on the molecular scale – and green chemistry and engineering, which aim to minimize environmental impacts through resource-conserving and waste-eliminating improvements in processes and products. It concludes with recommendations for proactive federal policy measures to help the fast developing field of nanotechnology to "grow up" green.

The report cites examples of research progress toward using nanotechnology to accomplish environmental goals in combination with commercial or other objectives. "With greater ability to manipulate matter and tailor properties, it should be possible to make products and processes with reduced toxicity, increased durability and improved energy efficiency," according to the report.

For example, James Hutchison, a University of Oregon chemist, uses DNA molecules in a novel process that holds promise for building nanoscale patterns on silicon chips and other surfaces. The experimental method saves materials and requires less water and solvent than the traditional printing – or lithography – techniques used in the deceptively resource-intensive electronics industry. Other researchers are investigating nanoscale approaches to replace lead and other toxic materials in electronics manufacturing.

Chemist Vicki Colvin and her Rice University colleagues have discovered that 12-nanometer magnetic nanoparticles can remove better than 99 percent of the arsenic in a solution, while their counterparts at Oklahoma State University have engineered nanoscale sensors that can detect pollutants at the level of parts per billion.

Nanotechnology has opened promising new routes for making inexpensive solar cells as well as improving the performance and lowering the cost of fuel cells, eyed as the energy source for cars and trucks of the future. At the same time, work at the nanoscale is leading toward tools for removing toxic materials and cleaning up hazardous waste sites.

"Nanotechnology potentially is a 'doubly green dream.' It offers us the opportunity to make products and processes 'green' from the beginning," explained Barbara Karn, an environmental scientist who helped organize the green nanotechnology programs while with the Project on Emerging Nanotechnologies. "It also allows us to substitute more environmentally-friendly chemicals, materials and manufacturing processes for older, more polluting ones."

The report defines four categories in which nanotechnology applications and environmental interests intersect:


Fostering new nanotechnology-enabled products and processes that are environmentally benign – or "clean and green";

Managing nanomaterials and their production to minimize potential environmental, health, and safety risks;

Using nanotechnology to clean up toxic waste site and other legacy pollution problems; and

Substituting green nanotechnology products for existing products that are less environmentally friendly.

"We think the United States is on track to be a global leader in green nanotech," said David Rejeski, director of the Project on Emerging Nanotechnologies. "The country's research and development portfolio should be directed toward this goal. We believe green nanotechnology can not only help protect the environment but also be a source of American jobs and company profits in the future."

Looking ahead, beyond legacy environmental problems of today, the report suggests that the most effective approach to protecting the environment would be to "develop green nano policies that actively promote pollution prevention."

Ranging from developing metrics for evaluating bottom-line environmental impacts to using federal procurement to foster demand for green nanoproducts, the recommended policy steps outlined in the report would help to ensure that the $8.3 billion taxpayer investment in nanotechnology, since the U.S. National Nanotechnology Initiative was established in 2001, pays off for the country and the environment.

"We are on an unsustainable path," said Paul Anastas, director of the American Chemical Society's Green Chemistry Institute. "It is not as though nanotechnology will be an option; it is going to be essential for coming up with sustainable technologies."


###
About Nanotechnology

Nanotechnology is the ability to measure, see, manipulate and manufacture things usually between 1 and 100 nanometers. A nanometer is one billionth of a meter; a human hair is roughly 100,000 nanometers wide. More than $30 billion in products incorporating nanotechnology were sold globally in 2005. By 2014, Lux Research estimates this figure will grow to $2.6 trillion.

The Project on Emerging Nanotechnologies is an initiative launched by the Woodrow Wilson International Center for Scholars and The Pew Charitable Trusts in 2005. It is dedicated to helping business, government and the public anticipate and manage possible health and environmental implications of nanotechnology. For more information about the project, log on to http://www.nanotechproject.org.

The Pew Charitable Trusts ( http://www.pewtrusts.org ) is driven by the power of knowledge to solve today's most challenging problems. Pew applies a rigorous, analytical approach to improve public policy, inform the public and stimulate civic life. We partner with a diverse range of donors, public and private organizations and concerned citizens who share our commitment to fact-based solutions and goal-driven investments to improve society.

The Woodrow Wilson International Center for Scholars is the living, national memorial to President Wilson established by Congress in 1968 and headquartered in Washington, D.C. The Center establishes and maintains a neutral forum for free, open, and informed dialogue. It is a nonpartisan institution, supported by public and private funds and engaged in the study of national and international affairs.

#15: Easing concerns about nanomaterials' impact on soil microbes Author: adediosLocation: Angel C. de Dios PostPosted: Mon Apr 30, 2007 8:22 am
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Easing concerns about nanomaterials' impact on soil microbes
30 April 2007
Environmental Science & Technology

In an advance toward understanding the environmental effects of manufactured nanomaterials, scientists in Indiana are reporting that fullerenes have little impact on natural microbes in soil. These communities of bacteria and other microorganisms play critical roles in soil health, which include the recycling of nutrients tied up in organic materials so they can be used by plants.

Ronald F. Turco and colleagues point out that nanomaterials may be released to the environment in the future, with emergence of a nanomaterials industry that involves large-scale manufacture of fullerenes (C60), carbon nanotubes and other substances. "Using C60 as a model, we provide the first report on the impact of manufactured nanomaterials on the microbial aspects of soil," the scientists state in a report scheduled for the May 1 issue of ACS' Environmental Science & Technology, a semi-monthly journal. "This is a key first step in establishing an understanding of the environmental impact of C60."

Previous studies suggested that carbon nanomaterials had a toxic effect on microbes. Nobody had run the test in soils before. The new study was done with soil that contained organic material and salts found naturally in soil. These materials may tie-up nanomaterials, thus reducing their bioavailability and toxicity, the researchers indicated.

ARTICLE ##2 FOR IMMEDIATE RELEASE "Impact of Fullerene (C60) on a Soil Microbial Community"

DOWNLOAD PDF http://pubs.acs.org/cgi-bin/sa.....61953l.pdf
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#16: Direct interconnections between nanowires and human cells Author: adediosLocation: Angel C. de Dios PostPosted: Mon Jun 04, 2007 10:48 am
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Direct interconnections between nanowires and human cells
Journal of the American Chemical Society
4 June 2007

Scientists in California are reporting an advance toward one of the futuristic goals nanobiology and nanomedicine — developing technology for "wiring" together individual cells and connecting cells via nanowires to external sensors and other devices.

In a study scheduled for the June 20 issue of Journal of the American Chemical Society, a weekly publication, Bruce R. Conklin and Peidong Yang and colleagues report what they term the first demonstration of a direct nanowire connection to individual mammalian cells without the use of force that can damage or kill cells. They connected human embryonic kidney cells and mouse embryonic stem cells to silicon nanowires, using an approach in which the wires penetrated into cells naturally as the cells grew in cultures. The cells survived for days, and researchers were able to derive and maintain heart muscle cells from the mouse embryonic stem cells.

"Direct interconnection of the cells to the external world by interfacing nanomaterials may afford great opportunities to probe and manipulate biological processes occurring inside cells, across membranes, and between neighboring cells," their report states. "Our results suggest that the nanowires can be potentially utilized as a powerful tool for studying intra- and inter-cellular biological processes."

ARTICLE #4 FOR IMMEDIATE RELEASE "Interfacing Silicon Nanowires with Mammalian Cells"

DOWNLOAD PDF http://pubs.acs.org/cgi-bin/sa.....71456k.pdf
DOWNLOAD HTML http://pubs.acs.org/cgi-bin/sa.....1456k.html

#17: Nanoparticles hitchhike on red blood cells: a potential new Author: adediosLocation: Angel C. de Dios PostPosted: Wed Jun 27, 2007 8:55 am
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Society for Experimental Biology and Medicine
27 June 2007

Nanoparticles hitchhike on red blood cells: a potential new method for drug delivery


Researchers at the University of California, Santa Barbara have discovered that attaching polymeric nanoparticles to the surface of red blood cells dramatically increases the in vivo lifetime of the nanoparticles. The research, published in the July 07 issue of Experimental Biology and Medicine, could offer applications for the delivery of drugs and circulating bioreactors.

Polymeric nanoparticles are excellent carriers for delivering drugs. They protect drugs from degradation until they reach their target and provide sustained release of drugs. Polymeric nanoparticles, however, suffer from one major limitation: they are quickly removed from the blood, sometimes in minutes, rendering them ineffective in delivering drugs.

The research team, led by Samir Mitragotri, a professor of chemical engineering, and Elizabeth Chambers, a recent doctoral graduate, found that nanoparticles can be forced to remain in the circulation when attached to red blood cells. The particles eventually detach from the blood cells due to shear forces and cell-to-cell interactions, and are cleared from the system by the liver and spleen. Red blood cell circulation is not affected by attaching the nanoparticles.

“Attachment of polymeric nanoparticles to red blood cells combines the advantages of the long circulating lifetime of the red blood cell, and their abundance, with the robustness of polymeric nanoparticles,” said Mitragotri. “Using red blood cells to extend the circulation time of the particles avoids the need to modify the surface chemistry of the entire particle, which offers the potential to attach chemicals to the exposed surface for targeting applications.”

The researchers have learned that particles adhered to red blood cells can escape phagocytosis because red blood cells have a knack for evading macrophages. Nanoparticles aren’t the first to be piggybacking on red blood cells; the strategy has already been adopted by certain bacteria, such as hemobartonella, that adhere to RBCs and can remain in circulation for several weeks.

The researchers say that it may be possible to keep the nanoparticles in circulation for a relatively long time, theoretically up to the circulation lifetime of a red blood cell – which is 120 days – if the binding between particles and the red blood cells is strengthened. The methodology is applicable to drugs that are effective while still attached to a red blood cell, although the researchers say that slow release from the red blood cell surface is also feasible.

Mitragotri says “this mode of prolonging particle circulation has significant implications in drug delivery, potentially leading to new treatments for a broad variety of conditions such as cancer, blood clots and heart disease”. Dr. Steven R. Goodman, Editor-in-Chief of the journal, said “this study dealing with the attachment of nanoparticles to red blood cells may also have important implications for future treatment of hematologic disorders. This fusion of modern nanobioscience with cell biology and hematology is precisely the type of interdisciplinary study that the new Experimental Biology and Medicine is interested in publishing.” Experimental Biology and Medicine is a journal dedicated to the publication of multidisciplinary and interdisciplinary research in the biomedical sciences.

###
Experimental Biology and Medicine is the journal of the Society of Experimental Biology and Medicine. To learn about the benefits of society membership visit www.sebm.org
If you are interested in publishing in the journal please visit www.ebmonline.org

#18: Tough Tubes: Carbon Nanotubes Endure Heavy Wear and Tear Author: adediosLocation: Angel C. de Dios PostPosted: Tue Jul 03, 2007 9:32 am
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July 2, 2007
Rensselaer University

Tough Tubes: Carbon Nanotubes Endure Heavy Wear and Tear

The ability of carbon nanotubes to withstand repeated stress yet retain their structural and mechanical integrity is similar to the behavior of soft tissue, according to a new study from Rensselaer Polytechnic Institute.

When paired with the strong electrical conductivity of carbon nanotubes, this ability to endure wear and tear, or fatigue, suggests the materials could be used to create structures that mimic artificial muscles or interesting electro-mechanical systems, researchers said.

For the full article:

http://news.rpi.edu/update.do?.....ppvar=page(1)

#19: Nano Wagon Wheels Author: adediosLocation: Angel C. de Dios PostPosted: Sat Jul 07, 2007 7:15 am
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Press Release
Angewandte Chemie International Edition ,
doi: 10.1002/anie.200701614
5 July 2007

Nr. 27/2007

Nano Wagon Wheels

Researchers synthesize molecule shaped like a wagon wheel
Contact: Sigurd Höger, Universität Bonn (Germany)

Molecularly Defined Shape-Persistent 2D Oligomers: The Covalent-Template Approach to Molecular Spoked Wheels

It looks like a tiny wagon wheel: Scanning tunneling microscope images published in the journal Angewandte Chemie depict giant molecules with a diameter of 7 nm, whose “hub”, “spokes”, and “rim” are clearly recognizable. This unusual, highly symmetric structure was made by a team led by Sigurd Höger (University of Bonn); the pictures were taken by a Belgian team headed by Steven De Feyter (Kath. Univ. Leuven).

Two-dimensional particles, such as inorganic alumina platelets, are used as fillers for plastics because they impart excellent mechanical properties to these materials. Nanocomposites made of alumina platelets and polymers are thus extraordinarily rigid, strong, and thermally stable materials. The barrier properties of plastics with respect to liquids and gasses, such as oxygen, could be improved by the addition of nanoscopic platelets. This would be useful for applications such as food packaging, and makes less expensive, more environmentally friendly plastics accessible.

To better understand the way in which the platelets work, several researchers have been working with synthetic alumina platelets. One area of interest is the use of large organic molecules in the form of rigid disks. Their advantage: They can be produced with uniform shapes and sizes. Also, their chemical properties can be adjusted as needed by the attachment of additional functional groups. Until now, organic molecular disks could not be made as large as the inorganic originals they are intended to imitate. The team from the Universities of Bonn and Leuven has now jumped this hurdle: They have successfully synthesized very large wheel-shaped molecules.

Starting from a rigid, star-shaped “hub”, the researchers added additional rigid molecular building blocks to form six “spokes”. Finally, the parts of the molecule were connected to form a continuous “rim”. The rigid linear molecules used contain aromatic six-membered rings as well as carbon–carbon triple bonds. Additional groups attached to the spokes provide the solubility required for the experiments to be carried out on these molecules.

In the next step, the researchers will attempt to grow these little wheels bit by bit by adding more building blocks onto the rim. This should result in structures resembling a spider web.

#20: Tomorrow's green nanofactories Author: adediosLocation: Angel C. de Dios PostPosted: Mon Jul 09, 2007 11:23 am
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Project on Emerging Nanotechnologies

Tomorrow's green nanofactories
9 July 2007

New podcast explores how viruses produce eco-friendly batteries
WASHINGTON, DC—Viruses are notorious villains. They cause serious human diseases like AIDS, polio, and influenza, and can lead to system crashes and data loss in computers.

A new podcast explores how nanotechnology researcher Angela Belcher, from Massachusetts Institute of Technology (MIT), is working with viruses to make them do good things. By exploiting a virus’s ability to replicate rapidly and combine with semiconductor and electronic materials, she is coaxing them to grow and self-assemble nanomaterials into a functional electronic device. Through this marriage of nanotechnology with green chemistry, Belcher and her team are working toward building faster, better, cheaper and environmentally-friendly transistors, batteries, solar cells, diagnostic materials for detecting cancer, and semiconductors for use in modern electrical devices—everything from computers to cell phones.

Unlike traditional semiconductor or battery manufacturing which requires expensive and toxic chemicals, Belcher’s nanofactories generate little waste, grow at room temperature, and promise to be inexpensive and largely biodegradable.

Does all this sound too good to be true" Judge for yourself. Listen to an interview with Dr. Belcher, a 2004 winner of a MacArthur Foundation “Genius Award.” It is second in an exciting new series of podcasts called Trips to the NanoFrontier. These podcasts are available online at www.penmedia.org/podcast , or directly from Apple’s iTunes music store.

These podcasts and a recent publication, NanoFrontiers: Visions for the Future ( www.nanotechproject.org/114 ), are written by freelance science writer Karen F. Schmidt. Both focus on nanotechnology’s ability to address the energy crisis, the need for better medical treatments, and the demand for clean water. They are based on a two-day NanoFrontiers forecasting workshop held in February 2006, sponsored by the National Science Foundation (NSF), National Institutes of Health (NIH), and the Project on Emerging Nanotechnologies, which is an initiative of the Woodrow Wilson International Center for Scholars and The Pew Charitable Trusts.

“Nanotechnology is the future. In 2006 alone, governments, corporations, and venture capitalists spent $12 billion on nanotechnology research and development worldwide. Nanotechnology promises to change just about everything—our medical care, energy sources, communications and food. It is leading us to what many in government and industry are calling ‘The Next Industrial Revolution.’ Society needs to prepare now for how to exploit and harness its potential, especially to ensure that nanotechnology makes possible a greener, more sustainable tomorrow,” said David Rejeski, director of the Project on Emerging Nanotechnologies at the Wilson Center.

“Dr. Belcher’s research with viruses, proteins and yeast offers hope for new, ground-breaking solutions to the world’s energy problems. It holds out the prospect of using nanotechnology in a variety of ways, ranging from improving the efficiency of production, storage, and transmission of energy to overcoming many of the obstacles to a hydrogen-based transportation system based on fuel-cell powered cars and trucks,” according to Rejeski.


###
About Nanotechnology

Nanotechnology entails the measurement, prediction and construction of materials on the scale of atoms and molecules. A nanometer is one-billionth of a meter, and nanotechnology typically deals with particles and structures larger than 1 nanometer, but smaller than 100 nanometers. To put this into perspective, the width of a human hair is approximately 80,000 nanometers. In 2014, Lux Research estimates that $2.6 trillion in manufactured goods will incorporate nanotech, or about 15 percent of total global output.

The Project on Emerging Nanotechnologies is an initiative launched by the Woodrow Wilson International Center for Scholars and The Pew Charitable Trusts in 2005. It is dedicated to helping business, government and the public anticipate and manage possible health and environmental implications of nanotechnology. For more information about the project, log on to www.nanotechproject.org

#21: Ancient Peppers Reveal Early Taste for Heat Author: adediosLocation: Angel C. de Dios PostPosted: Tue Jul 10, 2007 7:52 am
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Ancient Peppers Reveal Early Taste for Heat
By Jeanna Bryner, LiveScience Staff Writer

posted: 09 July 2007 05:14 pm ET

Shriveled peppers preserved for 1,500 years in two caves in southern Mexico are giving scientists a real taste of pre-Columbian agriculture and the spicy fare it yielded.

The desiccated chilies belong to Capsicum annum, which includes modern-day jalapenos and ancho peppers, and Capsicum frutescens, whose most famous member is the Tabasco pepper. Two of the peppers look similar to today’s Tabasco and cayenne varieties.

The plant remains, described today online in the journal Proceedings of the National Academy of Sciences, were discovered in Guila Naquiz and Silvia’s Cave, two dry rock shelters in the Valley of Oaxaca in southern Mexico. They were so well-preserved that researchers were able to distinguish seven cultivated types from Guila Naquitz and three from Silvia’s Cave.

“This shows there was very complex agriculture and really interesting food, because you don’t grow seven different kinds of peppers if you’re not making some really interesting food,” said lead author Linda Perry of the Smithsonian’s National Museum of Natural History in Washington, D.C.

For the full article:

http://www.livescience.com/his....._find.html

#22: Nano propellers pump with proper chemistry Author: adediosLocation: Angel C. de Dios PostPosted: Mon Jul 16, 2007 11:47 am
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University of Illinois at Chicago
16 July 2007

Nano propellers pump with proper chemistry

The ability to pump liquids at the cellular scale opens up exciting possibilities, such as precisely targeting medicines and regulating flow into and out of cells. But designing this molecular machinery has proven difficult.

Now chemists at the University of Illinois at Chicago have created a theoretical blueprint for assembling a nanoscale propeller with molecule-sized blades.

The work is featured in Research Highlights in the July 12 issue of Nature and was described in the June 28 cover story of Physical Review Letters.

Using classical molecular dynamics simulations, Petr Král, assistant professor of chemistry at UIC, and his laboratory coworkers were able to study realistic conditions in this microscopic environment to learn how the tiny propellers pump liquids.

While previous research has looked at how molecular devices rotate in flowing gases, Král and his group are the first to look at molecular propeller pumping of liquids, notably water and oils.

"We want to see what happens when the propellers get to the scale where it's impossible to reduce the size of the blades any more," said Král.

Král's group found that at the molecular level -- unlike at the macro level -- the chemistry of the propeller's blades and their sensitivity to water play a big role in determining whether the propeller pumps efficiently or just spins with little effect. If the blades have a hydrophobic, or water-repelling nature, they pump a lot of water. But if they are hydrophilic -- water-attracting -- they become clogged with water molecules and pump poorly.

"Pumping rates and efficiencies in the hydrophilic and hydrophobic forms can differ by an order of magnitude, which was not expected," he said.

The UIC researchers found that propeller pumping efficiency in liquids is highly sensitive to the size, shape, chemical or biological composition of the blades.

"In principle, we could even attach some biological molecules to the blades and form a propeller that would work only if other molecules bio-compatible with the blades are in the pumped solution," he said.

The findings present new factors to consider in developing nanoscale liquid-pumping machines, but Král added that such technology probably won't become reality for several years, given the difficult nature of constructing such ultra-small devices.

Král's laboratory studies how biological systems, like tiny flagella that move bacteria, offer clues for building motors, motile systems and other nanoscale devices in a hybrid environment that combines biological and inorganic chemistry.

"The 21st century will be about hybrid biological and artificial nanoscale systems and their mutual co-evolution," Král predicts. "My group alone is working on about a half-dozen such projects. I'm optimistic about such nanoscale developments."


###
The PRL article was co-authored by UIC chemistry graduate student Boyang Wang.

#23: Nano-sized generator gets big power boost Author: adediosLocation: Angel C. de Dios PostPosted: Mon Jul 23, 2007 9:35 am
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Nano-sized generator gets big power boost
23 July 2007
Nano Letters

The notion of generating electricity from flowing blood, pulsating blood vessels, or a beating heart may seem like science fiction. But scientists are reporting a stride in that direction in the August 8 issue of ACS’ Nano Letters, a monthly journal, with development a more powerful nanogenerator for powering implantable biomedical devices and other small electronics.

In the report, Zhong Lin Wang and colleagues explain that such nano-devices show great promise for biosensing, environmental monitoring and personal electronics. Lacking, however, are practical ways to power these devices. The report discusses a prototype nanogenerator, developed earlier, which consists of zinc oxide nanowires and could turn mechanical energy into electricity.

Researchers now describe an improved version of the device, which produces 20-30 times more electric current and is able to generate electricity while immersed in biological fluids or other liquids, using ultrasonic waves as the energy source. “It sets a solid foundation for self-powering implantable and wireless nanodevices and nanosystems in biofluid and any other type of liquid,” the report states.

ARTICLE #2 FOR IMMEDIATE RELEASE
“Integrated Nanogenerators in Biofluid”

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#24: Scientists Discover New Way to Study Nanostructures Author: adediosLocation: Angel C. de Dios PostPosted: Tue Jul 24, 2007 5:10 pm
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Scientists Discover New Way to Study Nanostructures
Georgia Institute of Technology

Atlanta (July 24, 2007) — Scientists at the Georgia Institute of Technology have discovered a phenomenon which allows measurement of the mechanical motion of nanostructures by using the AC Josephson effect. The findings, which may be used to identify and characterize structural and mechanical properties of nanoparticles, including materials of biological interest, appear online in the journal Nature Nanotechnology.

For the full article:

http://www.gatech.edu/news-roo.....hp?id=1433

#25: Potato chip flavoring boosts longevity of concrete Author: adediosLocation: Angel C. de Dios PostPosted: Mon Aug 06, 2007 12:04 pm
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Potato chip flavoring boosts longevity of concrete
6 August 2007
Industrial & Engineering Chemistry Research

The ingredient that helps give “salt & vinegar” potato chips that tangy snap is the key to a new waterproof coating for protecting concrete from water damage, according to a study scheduled for the current (August 1) issue of ACS’ Industrial & Engineering Chemistry Research, a bi-weekly journal.

Awni Al-Otoom and colleagues in Jordan point out that concrete’s unique properties have made it the world’s most widely used structural material. Concrete, however, is so porous that water soaks in, corroding steel reinforcing bars and meshes that strengthen concrete roads and buildings and causing cracks as water expands and contracts during freeze-thaw cycles. Sealants are commercially available, but they have serious shortcomings, the study notes.

In the new report, researchers describe the use of sodium acetate as an inexpensive and environmentally friendly concrete sealant. One of sodium acetate’s many uses is in flavored potato chips. In laboratory studies using freshly made concrete, the researchers showed that sodium acetate seeps into pores in concrete and then hardens and crystallizes upon exposure to water. The resultant swelling blocks entry of additional moisture, they said. Under dry conditions, the crystals shrink back to their original size and allow moisture to evaporate. The net result is “a significant reduction in water permeability,” that “can be expected to increase the service life of the concrete,” the report said.

ARTICLE #1 FOR IMMEDIATE RELEASE “Crystallization Technology for Reducing Water Permeability into Concrete”

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