Tag Archives: University at Buffalo

When nanoparticles collide

The science of collisions, although it looks more like kissing to me, at the nanoscale could lead to some helpful discoveries according to an April 5, 2018 news item on Nanowerk,

Helmets that do a better job of preventing concussions and other brain injuries. Earphones that protect people from damaging noises. Devices that convert “junk” energy from airport runway vibrations into usable power.

New research on the events that occur when tiny specks of matter called nanoparticles smash into each other could one day inform the development of such technologies.

Before getting to the news release proper, here’s a gif released by the university,

A digital reconstruction shows how individual atoms in two largely spherical nanoparticles react when the nanoparticles collide in a vacuum. In the reconstruction, the atoms turn blue when they are in contact with the opposing nanoparticle. Credit: Yoichi Takato

An April 4, 2018 University at Buffalo news release (also on EurekAlert) by Charlotte Hsu, which originated the news item, fills in some details,

Using supercomputers, scientists led by the University at Buffalo modeled what happens when two nanoparticles collide in a vacuum. The team ran simulations for nanoparticles with three different surface geometries: those that are largely circular (with smooth exteriors); those with crystal facets; and those that possess sharp edges.

“Our goal was to lay out the forces that control energy transport at the nanoscale,” says study co-author Surajit Sen, PhD, professor of physics in UB’s College of Arts and Sciences. “When you have a tiny particle that’s 10, 20 or 50 atoms across, does it still behave the same way as larger particles, or grains? That’s the guts of the question we asked.”

“The guts of the answer,” Sen adds, “is yes and no.”

“Our research is useful because it builds the foundation for designing materials that either transmit or absorb energy in desired ways,” says first author Yoichi Takato, PhD. Takato, a physicist at AGC Asahi Glass and former postdoctoral scholar at the Okinawa Institute of Science and Technology in Japan, completed much of the study as a doctoral candidate in physics at UB. “For example, you could potentially make an ultrathin material that is energy absorbent. You could imagine that this would be practical for use in helmets and head gear that can help to prevent head and combat injuries.”

The study was published on March 21 in Proceedings of the Royal Society A by Takato, Sen and Michael E. Benson, who completed his portion of the work as an undergraduate physics student at UB. The scientists ran their simulations at the Center for Computational Research, UB’s academic supercomputing facility.

What happens when nanoparticles crash

The new research focused on small nanoparticles — those with diameters of 5 to 15 nanometers. The scientists found that in collisions, particles of this size behave differently depending on their shape.

For example, nanoparticles with crystal facets transfer energy well when they crash into each other, making them an ideal component of materials designed to harvest energy. When it comes to energy transport, these particles adhere to scientific norms that govern macroscopic linear systems — including chains of equal-sized masses with springs in between them — that are visible to the naked eye.

In contrast, nanoparticles that are rounder in shape, with amorphous surfaces, adhere to nonlinear force laws. This, in turn, means they may be especially useful for shock mitigation. When two spherical nanoparticles collide, energy dissipates around the initial point of contact on each one instead of propagating all the way through both. The scientists report that at crash velocities of about 30 meters per second, atoms within each particle shift only near the initial point of contact.

Nanoparticles with sharp edges are less predictable: According to the new study, their behavior varies depending on sharpness of the edges when it comes to transporting energy.
Designing a new generation of materials

“From a very broad perspective, the kind of work we’re doing has very exciting prospects,” Sen says. “It gives engineers fundamental information about nanoparticles that they didn’t have before. If you’re designing a new type of nanoparticle, you can now think about doing it in a way that takes into account what happens when you have very small nanoparticles interacting with each other.”

Though many scientists are working with nanotechnology, the way the tiniest of nanoparticles behave when they crash into each other is largely an open question, Takato says.

“When you’re designing a material, what size do you want the nanoparticle to be? How will you lay out the particles within the material? How compact do you want it to be? Our study can inform these decisions,” Takato says.

Here’s a link to and a citation for the paper,

Small nanoparticles, surface geometry and contact forces by Yoichi Takato, Michael E. Benson, Surajit Sen. Proceedings of the Royal Society A (Mathematical, Physical, and Engineering Sciences) Published 21 March 2018.DOI: 10.1098/rspa.2017.0723

This paper is behind a paywall.

Drink your spinach juice—illuminate your guts

Contrast agents used for magnetic resonance imaging, x-ray imaging, ultrasounds, and other imaging technologies are not always kind to the humans ingesting them. So, scientists at the University at Buffalo (also known as the State University of New York at Buffalo) have developed a veggie juice that does the job according to a July 11, 2016 news item on Nanowerk (Note: A link has been removed),

The pigment that gives spinach and other plants their verdant color may improve doctors’ ability to examine the human gastrointestinal tract.

That’s according to a study, published in the journal Advanced Materials (“Surfactant-Stripped Frozen Pheophytin Micelles for Multimodal Gut Imaging”), which describes how chlorophyll-based nanoparticles suspended in liquid are an effective imaging agent for the gut.

The University of Buffalo has provided an illustration of the work,

A new UB-led study suggests that chlorophyll-based nanoparticles are an effective imaging agent for the gut. The medical imaging drink, developed to diagnose and treat gastrointestinal illnesses, is made of concentrated chlorophyll, the pigment that makes spinach green. Photo illustration credit: University at Buffalo.

A new UB-led study suggests that chlorophyll-based nanoparticles are an effective imaging agent for the gut. The medical imaging drink, developed to diagnose and treat gastrointestinal illnesses, is made of concentrated chlorophyll, the pigment that makes spinach green. Photo illustration credit: University at Buffalo.

A July 11, 2016 University at Buffalo (UB) news release (also on EurekAlert) by Cory Nealon, which originated the news item, expands on the theme,

“Our work suggests that this spinach-like, nanoparticle juice can help doctors get a better look at what’s happening inside the stomach, intestines and other areas of the GI tract,” says Jonathan Lovell, PhD, assistant professor in the Department of Biomedical Engineering, a joint program between UB’s School of Engineering and Applied Sciences and the Jacobs School of Medicine and Biomedical Sciences at UB, and the study’s corresponding author.

To examine the gastrointestinal tract, doctors typically use X-rays, magnetic resonance imaging or ultrasounds, but these techniques are limited with respect to safety, accessibility and lack of adequate contrast, respectively.

Doctors also perform endoscopies, in which a tiny camera attached to a thin tube is inserted into the patient’s body. While effective, this procedure is challenging to perform in the small intestine, and it can cause infections, tears and pose other risks.

The new study, which builds upon Lovell’s previous medical imaging research, is a collaboration between researchers at UB and the University of Wisconsin-Madison. It focuses on Chlorophyll a, a pigment found in spinach and other green vegetables that is essential to photosynthesis.

In the laboratory, researchers removed magnesium from Chlorophyll a, a process which alters the pigment’s chemical structure to form another edible compound called pheophytin. Pheophytin plays an important role in photosynthesis, acting as a gatekeeper that allows electrons from sunlight to enter plants.

Next, they dissolved pheophytin in a solution of soapy substances known as surfactants. The researchers were then able to remove nearly all of the surfactants, leaving nearly pure pheophytin nanoparticles.

The drink, when tested in mice, provided imaging of the gut in three modes: photoacoustic imaging, fluorescence imaging and positron emission tomography (PET). (For PET, the researchers added to the drink Copper-64, an isotope of the metal that, in small amounts, is harmless to the human body.)

Additional studies are needed, but the drink has commercial potential because it:

·         Works in different imaging techniques.

·         Moves stably through the gut.

·         And is naturally consumed in the human diet already.

In lab tests, mice excreted 100 percent of the drink in photoacoustic and fluorescence imaging, and nearly 93 percent after the PET test.

“The veggie juice allows for techniques that are not commonly used today by doctors for imaging the gut like photoacoustic, PET, and fluorescence,” Lovell says. “And part of the appeal is the safety of the juice.”

Here’s a link to and a citation for the paper,

Surfactant-Stripped Frozen Pheophytin Micelles for Multimodal Gut Imaging by Yumiao Zhang, Depeng Wang, Shreya Goel, Boyang Sun, Upendra Chitgupi, Jumin Geng, Haiyan Sun, Todd E. Barnhart, Weibo Cai, Jun Xia, and Jonathan F. Lovell. Advanced Materials DOI: 10.1002/adma.201602373 Version of Record online: 11 JUL 2016

© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

This paper is behind a paywall.

US Navy invests in graphene

More usually, I feature research from DARPA (Defense Advanced Research Progects Agency) which I think belongs to the US Army and the US Air Force Research Office. The US Navy has featured here only once before (a Nov. 1, 2011 posting) and even then it was tangentially. I think it’s long past time that the US Navy gets some attention.

A July 22, 2015 news item on Nanowerk explains the Navy’s interest in electricity and graphene,

The U.S. Navy distributes electricity aboard most of its ships like a power company. It relies on conductors, transformers and other bulky infrastructure.

The setup works, but with powerful next generation weapons on the horizon and the omnipresent goal of energy efficiency, the Navy is seeking alternatives to conventional power control systems.

One option involves using graphene, which, since its discovery in 2004, has become the material of choice for researchers working to improve everything from solar cells to smartphone batteries.

Accordingly, the Office of Naval Research has awarded University at Buffalo engineers an $800,000 grant to develop narrow strips of graphene called nanoribbons that may someday revolutionize how power is controlled in ships, smartphones and other electronic devices.

A July 20, 2015 University of Buffalo news release by Cory Nealon, which originated the news item, expands on the theme,

“We need to develop new nanomaterials capable of handling greater amounts of energy densities in much smaller devices. Graphene nanoribbons show remarkable promise in this endeavor,” says Cemal Basaran, PhD, a professor in UB’s Department of Civil, Structural and Environmental Engineering, School of Engineering and Applied Sciences, and the grant’s principal investigator.

Graphene is a single layer of carbon atoms packed together like a honeycomb. It is extremely thin, light and strong. It’s also the best known conductor of heat and electricity.

“The beauty of graphene is that it can be grown like biological organisms as opposed to manufacturing materials with traditional techniques,” says Basaran, director of UB’s Electronic Packaging Laboratory and a researcher in UB’s New York State Center of Excellence in Materials Informatics. “These bio-inspired materials allow us to control their atomic organizations like controlling genetic DNA makeup of a lab-grown cell.”

While promising, researchers are just beginning to understand graphene and its potential uses. One area of interest is power control systems.

Like overhead power lines, most ships rely on copper or other metals to move electricity. Unfortunately, this process is relatively inefficient; electrons bash into each other and create heat in a process called Joule heating.

“You lose a great deal of energy that way,” Basaran says. “With graphene, you avoid those collisions because it conducts electricity in a different process, known as semi-ballistic conduction. It’s like a high-speed bullet train versus bumper cars.”

Another limitation of metal-based power distribution is the bulky infrastructure – transistors, copper wires, transformers, etc. – needed to move electricity. Whether in a ship or tablet computer, the components take up space and add weight.

Graphene nanoribbons offer a potential solution because they can act as both a conductor (instead of copper) and semiconductor (instead of silicon). Moreover, their ability to withstand failure under extreme energy loads is roughly 1,000 times greater than copper.

That bodes well for the Navy, which, like segments of the automotive industry, is pivoting toward electric vehicles.

It recently launched an all-electric destroyer; the ship’s propellers and drive shafts are turned by electric motors, as opposed to being connected to combustion engines. The integrated power-generation and distribution system may also be used to fire next generation weapons, such as railguns and powerful lasers. And the automation has allowed the Navy to reduce the ship’s crew, which places fewer sailors in potentially dangerous situations.

Graphene nanoribbons could improve these systems by making them more robust and energy-efficient, Basaran said. He and a team of researchers will:

·         Design complex simulations that examine how graphene nanoribbons can be used as a power switch.

·         Explore how adding hydrogen and other elements, a process known as “doping,” to graphene nanoribbons could improve their performance.

·         Investigate graphene nanoribbons’ failure limit under high power loads and try to find ways to improve it.

The research will be performed over the next four years.

I was particularly intrigued by the caption for this image included with the news release,

The technology may lead to more powerful weapons, energy savings and reduced crew numbers [Downloaded from http://www.buffalo.edu/news/releases/2015/07/021.html]

The technology may lead to more powerful weapons, energy savings and reduced crew numbers [Downloaded from http://www.buffalo.edu/news/releases/2015/07/021.html]

Presumably “reduced crew numbers’ means fewer jobs. I wonder if they’ll figure out that people without jobs are without money to pay taxes to fund these projects.

Nanojuice in your gut

A July 7, 2014 news item on Azonano features a new technique that could help doctors better diagnose problems in the intestines (guts),

Located deep in the human gut, the small intestine is not easy to examine. X-rays, MRIs and ultrasound images provide snapshots but each suffers limitations. Help is on the way.

University at Buffalo [State University of New York] researchers are developing a new imaging technique involving nanoparticles suspended in liquid to form “nanojuice” that patients would drink. Upon reaching the small intestine, doctors would strike the nanoparticles with a harmless laser light, providing an unparalleled, non-invasive, real-time view of the organ.

A July 5, 2014 University of Buffalo news release (also on EurekAlert) by Cory Nealon, which originated the news item, describes some of the challenges associated with medical imaging of small intestines,

“Conventional imaging methods show the organ and blockages, but this method allows you to see how the small intestine operates in real time,” said corresponding author Jonathan Lovell, PhD, UB assistant professor of biomedical engineering. “Better imaging will improve our understanding of these diseases and allow doctors to more effectively care for people suffering from them.”

The average human small intestine is roughly 23 feet long and 1 inch thick. Sandwiched between the stomach and large intestine, it is where much of the digestion and absorption of food takes place. It is also where symptoms of irritable bowel syndrome, celiac disease, Crohn’s disease and other gastrointestinal illnesses occur.

To assess the organ, doctors typically require patients to drink a thick, chalky liquid called barium. Doctors then use X-rays, magnetic resonance imaging and ultrasounds to assess the organ, but these techniques are limited with respect to safety, accessibility and lack of adequate contrast, respectively.

Also, none are highly effective at providing real-time imaging of movement such as peristalsis, which is the contraction of muscles that propels food through the small intestine. Dysfunction of these movements may be linked to the previously mentioned illnesses, as well as side effects of thyroid disorders, diabetes and Parkinson’s disease.

The news release goes on to describe how the researchers manipulated dyes that are usually unsuitable for the purpose of imaging an organ in the body,

Lovell and a team of researchers worked with a family of dyes called naphthalcyanines. These small molecules absorb large portions of light in the near-infrared spectrum, which is the ideal range for biological contrast agents.

They are unsuitable for the human body, however, because they don’t disperse in liquid and they can be absorbed from the intestine into the blood stream.

To address these problems, the researchers formed nanoparticles called “nanonaps” that contain the colorful dye molecules and added the abilities to disperse in liquid and move safely through the intestine.

In laboratory experiments performed with mice, the researchers administered the nanojuice orally. They then used photoacoustic tomography (PAT), which is pulsed laser lights that generate pressure waves that, when measured, provide a real-time and more nuanced view of the small intestine.

The researchers plan to continue to refine the technique for human trials, and move into other areas of the gastrointestinal tract.

Here’s an image of the nanojuice in the guts of a mouse,

The combination of "nanojuice" and photoacoustic tomography illuminates the intestine of a mouse. (Credit: Jonathan Lovell)

The combination of “nanojuice” and photoacoustic tomography illuminates the intestine of a mouse. (Credit: Jonathan Lovell)

This is an international collaboration both from a research perspective and a funding perspective (from the news release),

Additional authors of the study come from UB’s Department of Chemical and Biological Engineering, Pohang University of Science and Technology in Korea, Roswell Park Cancer Institute in Buffalo, the University of Wisconsin-Madison, and McMaster University in Canada.

The research was supported by grants from the National Institutes of Health, the Department of Defense and the Korean Ministry of Science, ICT and Future Planning.

Here’s a link to and a citation for the paper,

Non-invasive multimodal functional imaging of the intestine with frozen micellar naphthalocyanines by Yumiao Zhang, Mansik Jeon, Laurie J. Rich, Hao Hong, Jumin Geng, Yin Zhang, Sixiang Shi, Todd E. Barnhart, Paschalis Alexandridis, Jan D. Huizinga, Mukund Seshadri, Weibo Cai, Chulhong Kim, & Jonathan F. Lovell. Nature Nanotechnology (2014) doi:10.1038/nnano.2014.130 Published online 06 July 2014

This paper is behind a paywall.

Zimbabwe and its international nanotechnology center, ZINC

A Sept.24, 2012 news item on Nanowerk provides information about a new nanotechnology center in Zimbabwe,

With 14 percent of Zimbabwe’s population living with HIV/AIDS and tuberculosis as a co-infection, the need for new drugs and new formulations of available treatments is crucial.

To address these issues, two of the University at Buffalo’s [UB] leading research centers, the Institute for Lasers, Photonics and Biophotonics (ILPB), and the New York State Center of Excellence in Bioinformatics and Life Sciences have signed on to launch the Zimbabwe International Nanotechnology Center (ZINC) — a national nanotechnology research program — with the University of Zimbabwe (UZ) and the Chinhoyi University of Technology (CUT).

This collaborative program will initially focus on research in nanomedicine and biosensors at UZ and energy at CUT. ZINC has grown out of the NIH [US National Institute of Health] Fogarty International Center, AIDS International Training and Research Program (AITRP) that was awarded to UB and UZ in 2008 to conduct HIV research training and build research capacity in Zimbabwe and neighboring countries in southern Africa.

I decided to find out more about Zimbabwe and found a map and details in a Wikipedia essay,

Location of Zimbabwe within the African Union (accessed Sept. 24, 2012 from the Wikipedia essay on Zimbabwe)

Zimbabwe (… officially the Republic of Zimbabwe) is a landlocked country located in Southern Africa, between the Zambezi and Limpopo rivers. It is bordered by South Africa to the south, Botswana to the southwest, Zambia and a tip of Namibia to the northwest (making this area a quadripoint) and Mozambique to the east. The capital is Harare. Zimbabwe achieved recognised independence from Britain in April 1980, following a 14-year period as an unrecognised state under the predominantly white minority government of Rhodesia, which unilaterally declared independence in 1965. Rhodesia briefly reconstituted itself as black-majority ruled Zimbabwe Rhodesia in 1979, but this order failed to gain international acceptance.

Zimbabwe has three official languages: English, Shona and Ndebele.

Getting back to Zimbabwe, Alan on the Science Business website posted on Sept. 24, 2012 about ZINC and the partnership (excerpted from the posting),

University at Buffalo in New York and two universities in the southern African nation of Zimbabwe will collaborate on a new nanotechnology research program in pharmacology. University of Zimbabwe in Harare and the Chinhoyi University of Technology in Mashonaland West, working with Buffalo’s Institute for Lasers, Photonics, and Biophotonics, along with New York State Center of Excellence in Bioinformatics and Life Sciences also on the Buffalo campus, will establish the Zimbabwe International Nanotechnology Center (ZINC).

ZINC aims to develop an international research and training capability in nanotechnology that advances the field as contributor to Zimbabwe’s economic growth. The collaboration is expected to focus on research in nanomedicine and biosensors for health care at University of Zimbabwe, while the Chinhoyi University of Technology partnership will conduct research related to energy.

The University of Buffalo Sept. 24, 2012 news release provides more details,

The UB ILPB and TPRC [Translational Pharmacy Research Core] collaboration recognized that the fields of pharmacology and therapeutics have increasingly developed links with emerging areas within the field of nanosciences in an attempt to develop tissue/organ targeted strategies that will lead to disease treatment and eradication. Research teams will focus on emerging technologies, initially focused in nanobiotechnology and nanomedicine for health care.

“Developing nanoformulations for HIV and tuberculosis diagnostics and therapeutics, as well as new tuberculosis drug development, are just a few of the innovative strategies to address these co-infections that this research collaboration can provide,” said Morse [Gene D. Morse, PharmD, Professor of Pharmacy Practice, associate director of the New York State Center of Excellence in Bioinformatics and Life Sciences and director of the Translational Pharmacy Research Core {TPRC}].

“In addition, the development of new nanotechnology-related products will jumpstart the economy and foster new economic initiatives in Zimbabwe that will yield additional private-public partnerships.”

Morse says that the current plans for a “Center of Excellence” in clinical and translational pharmacology in Harare at UZ will create a central hub in Africa, not just for Zimbabwe but for other countries to gain new training and capacity building in many exciting aspects of nanotechnology as well.

Good luck to ZINC and its partners!