Tag Archives: Brazil

Nanomaterials and UV (ultraviolet) light for environmental cleanups

I think this is the first time I’ve seen anything about a technology that removes toxic materials from both water and soil; it’s usually one or the other. A July 22, 2015 news item on Nanowerk makes the announcement (Note: A link has been removed),

Many human-made pollutants in the environment resist degradation through natural processes, and disrupt hormonal and other systems in mammals and other animals. Removing these toxic materials — which include pesticides and endocrine disruptors such as bisphenol A (BPA) — with existing methods is often expensive and time-consuming.

In a new paper published this week in Nature Communications (“Nanoparticles with photoinduced precipitation for the extraction of pollutants from water and soil”), researchers from MIT [Massachusetts Institute of Technology] and the Federal University of Goiás in Brazil demonstrate a novel method for using nanoparticles and ultraviolet (UV) light to quickly isolate and extract a variety of contaminants from soil and water.

A July 21, 2015 MIT news release by Jonathan Mingle, which originated the news item, describes the inspiration and the research in more detail,

Ferdinand Brandl and Nicolas Bertrand, the two lead authors, are former postdocs in the laboratory of Robert Langer, the David H. Koch Institute Professor at MIT’s Koch Institute for Integrative Cancer Research. (Eliana Martins Lima, of the Federal University of Goiás, is the other co-author.) Both Brandl and Bertrand are trained as pharmacists, and describe their discovery as a happy accident: They initially sought to develop nanoparticles that could be used to deliver drugs to cancer cells.

Brandl had previously synthesized polymers that could be cleaved apart by exposure to UV light. But he and Bertrand came to question their suitability for drug delivery, since UV light can be damaging to tissue and cells, and doesn’t penetrate through the skin. When they learned that UV light was used to disinfect water in certain treatment plants, they began to ask a different question.

“We thought if they are already using UV light, maybe they could use our particles as well,” Brandl says. “Then we came up with the idea to use our particles to remove toxic chemicals, pollutants, or hormones from water, because we saw that the particles aggregate once you irradiate them with UV light.”

A trap for ‘water-fearing’ pollution

The researchers synthesized polymers from polyethylene glycol, a widely used compound found in laxatives, toothpaste, and eye drops and approved by the Food and Drug Administration as a food additive, and polylactic acid, a biodegradable plastic used in compostable cups and glassware.

Nanoparticles made from these polymers have a hydrophobic core and a hydrophilic shell. Due to molecular-scale forces, in a solution hydrophobic pollutant molecules move toward the hydrophobic nanoparticles, and adsorb onto their surface, where they effectively become “trapped.” This same phenomenon is at work when spaghetti sauce stains the surface of plastic containers, turning them red: In that case, both the plastic and the oil-based sauce are hydrophobic and interact together.

If left alone, these nanomaterials would remain suspended and dispersed evenly in water. But when exposed to UV light, the stabilizing outer shell of the particles is shed, and — now “enriched” by the pollutants — they form larger aggregates that can then be removed through filtration, sedimentation, or other methods.

The researchers used the method to extract phthalates, hormone-disrupting chemicals used to soften plastics, from wastewater; BPA, another endocrine-disrupting synthetic compound widely used in plastic bottles and other resinous consumer goods, from thermal printing paper samples; and polycyclic aromatic hydrocarbons, carcinogenic compounds formed from incomplete combustion of fuels, from contaminated soil.

The process is irreversible and the polymers are biodegradable, minimizing the risks of leaving toxic secondary products to persist in, say, a body of water. “Once they switch to this macro situation where they’re big clumps,” Bertrand says, “you won’t be able to bring them back to the nano state again.”

The fundamental breakthrough, according to the researchers, was confirming that small molecules do indeed adsorb passively onto the surface of nanoparticles.

“To the best of our knowledge, it is the first time that the interactions of small molecules with pre-formed nanoparticles can be directly measured,” they write in Nature Communications.

Nano cleansing

Even more exciting, they say, is the wide range of potential uses, from environmental remediation to medical analysis.

The polymers are synthesized at room temperature, and don’t need to be specially prepared to target specific compounds; they are broadly applicable to all kinds of hydrophobic chemicals and molecules.

“The interactions we exploit to remove the pollutants are non-specific,” Brandl says. “We can remove hormones, BPA, and pesticides that are all present in the same sample, and we can do this in one step.”

And the nanoparticles’ high surface-area-to-volume ratio means that only a small amount is needed to remove a relatively large quantity of pollutants. The technique could thus offer potential for the cost-effective cleanup of contaminated water and soil on a wider scale.

“From the applied perspective, we showed in a system that the adsorption of small molecules on the surface of the nanoparticles can be used for extraction of any kind,” Bertrand says. “It opens the door for many other applications down the line.”

This approach could possibly be further developed, he speculates, to replace the widespread use of organic solvents for everything from decaffeinating coffee to making paint thinners. Bertrand cites DDT, banned for use as a pesticide in the U.S. since 1972 but still widely used in other parts of the world, as another example of a persistent pollutant that could potentially be remediated using these nanomaterials. “And for analytical applications where you don’t need as much volume to purify or concentrate, this might be interesting,” Bertrand says, offering the example of a cheap testing kit for urine analysis of medical patients.

The study also suggests the broader potential for adapting nanoscale drug-delivery techniques developed for use in environmental remediation.

“That we can apply some of the highly sophisticated, high-precision tools developed for the pharmaceutical industry, and now look at the use of these technologies in broader terms, is phenomenal,” says Frank Gu, an assistant professor of chemical engineering at the University of Waterloo in Canada, and an expert in nanoengineering for health care and medical applications.

“When you think about field deployment, that’s far down the road, but this paper offers a really exciting opportunity to crack a problem that is persistently present,” says Gu, who was not involved in the research. “If you take the normal conventional civil engineering or chemical engineering approach to treating it, it just won’t touch it. That’s where the most exciting part is.”

The researchers have made this illustration of their work available,

Nanoparticles that lose their stability upon irradiation with light have been designed to extract endocrine disruptors, pesticides, and other contaminants from water and soils. The system exploits the large surface-to-volume ratio of nanoparticles, while the photoinduced precipitation ensures nanomaterials are not released in the environment. Image: Nicolas Bertrand Courtesy: MIT

Nanoparticles that lose their stability upon irradiation with light have been designed to extract endocrine disruptors, pesticides, and other contaminants from water and soils. The system exploits the large surface-to-volume ratio of nanoparticles, while the photoinduced precipitation ensures nanomaterials are not released in the environment.
Image: Nicolas Bertrand Courtesy: MIT

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

Nanoparticles with photoinduced precipitation for the extraction of pollutants from water and soil by Ferdinand Brandl, Nicolas Bertrand, Eliana Martins Lima & Robert Langer. Nature Communications 6, Article number: 7765 doi:10.1038/ncomms8765 Published 21 July 2015

This paper is open access.

Herbicide nanometric sensor could help diagnose multiple sclerosis

This research into nanometric sensors and multiple sclerosis comes from Brazil. According to a June 23, 2015 news item on Nanowerk (Note: A link has been removed),

The early diagnosis of certain types of cancer, as well as nervous system diseases such as multiple sclerosis and neuromyelitis optica, may soon be facilitated by the use of a nanosensor capable of identifying biomarkers of these pathological conditions (“A Nanobiosensor Based on 4-Hydroxyphenylpyruvate Dioxygenase Enzyme for Mesotrione Detection”).

The nanobiosensor was developed at the Federal University of São Carlos (UFSCar), Sorocaba, in partnership with the São Paulo Federal Institute of Education, Science & Technology (IFSP), Itapetininga, São Paulo State, Brazil. It was originally designed to detect herbicides, heavy metals and other pollutants.

A June 23, 2015 Fundação de Amparo à Pesquisa do Estado de São Paulo news release on EurekAlert, which originated the news item, describes the sensor as it was originally used and explains its new function as a diagnostic tool for multiple sclerosis and other diseases,

“It’s a highly sensitive device, which we developed in collaboration with Alberto Luís Dario Moreau, a professor at IFSP. “We were able to increase sensitivity dramatically by going down to the nanometric scale,” said physicist Fábio de Lima Leite, a professor at UFSCar and the coordinator of the research group.

The nanobiosensor consists of a silicon nitride (Si3N4) or silicon (Si) nanoprobe with a molecular-scale elastic constant and a nanotip coupled to an enzyme, protein or other molecule.

When this molecule touches a target of interest, such as an antibody or antigen, the probe bends as the two molecules adhere. The deflection is detected and measured by the device, enabling scientists to identify the target.

“We started by detecting herbicides and heavy metals. Now we’re testing the device for use in detecting target molecules typical of nervous system diseases, in partnership with colleagues at leading centers of research on demyelinating diseases of the central nervous system”

The migration from herbicide detection to antibody detection was motivated mainly by the difficulty of diagnosing demyelinating diseases, cancer and other chronic diseases before they have advanced beyond an initial stage.

The criteria for establishing a diagnosis of multiple sclerosis or neuromyelitis optica are clinical (supplemented by MRI scans), and patients do not always present with a characteristic clinical picture. More precise diagnosis entails ruling out several other diseases.

The development of nanodevices will be of assistance in identifying these diseases and reducing the chances of false diagnosis.

The procedure can be as simple as placing a drop of the patient’s cerebrospinal fluid on a glass slide and observing its interaction with the nanobiosensor.

“If the interaction is low, we’ll be able to rule out multiple sclerosis with great confidence,” Leite said. “High interaction will indicate that the person is very likely to have the disease.” In this case, further testing would be required to exclude the possibility of a false positive.

“Different nervous system diseases have highly similar symptoms. Multiple sclerosis and neuromyelitis optica are just two examples. Even specialists experience difficulties or take a long time to diagnose them. Our technique would provide a differential diagnostic tool,” Leite said.

The next step for the group is to research biomarkers for these diseases that have not been completely mapped, including antibodies and antigens, among others. The group has begun tests for the detection of head and neck cancer.

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

A Nanobiosensor Based on 4-Hydroxyphenylpyruvate Dioxygenase Enzyme for Mesotrione Detection by P. Soto Garcia, A.L.D Moreau, J.C. Magalhaes Ierich,  A.C Araujo Vig, A.M. Higa, G.S. Oliveira, F. Camargo Abdalla, M. Hausen, & F.L. Leite. Sensors Journal, IEEE  (Volume:15 ,  Issue: 4) pp. 2106 – 2113 Date of Publication: 20 November 2014 Date of Current Version: 27 January 2015 Issue Date: April 2015  DOI 10.1109/JSEN.2014.2371773

This paper is behind a paywall.

South American countries and others visit Iran’s Nanotechnology Initiative Council

The Iran Nanotechnology Initiative Council (INIC) news release states eight South American countries visited. By my count there were six South American countries (Argentina, Brazil, Ecuador, Bolivia, Venezuela, and Uruguay,), one North American country (Mexico), and one Caribbean country (Cuba). All eight can be described as Latin American countries.

An easy to understand error (I once forgot Mexico is part of North America and, for heaven sakes, I live in Canada and really should know better) as the designations can be confusing. That cleared up, here’s what the June 15, 2015 INIC news release had to say about the visit,

The ambassadors and charge d’affaires of 8 South American countries of Argentina, Brazil, Ecuador, Bolivia, Cuba, Venezuela, Uruguay and Mexico paid a visit to Iran Nanotechnology Initiative Council (INIC) to become familiar with its activities.

Among the objectives of the visit, which was requested by the abovementioned countries, mention can be made of introduction with INIC and its activities, presentation of nanotechnology achievements and products in the country by the INIC, creation and modification of international cooperation and creation of appropriate environment for exporting nanotechnology-based products to these countries.

In this visit, the programs, achievements and objectives of nanotechnology development in Iran were explained by the authorities of INIC. In addition and due to the needs of the countries whose representatives were present in the visit, a number of experts from the Iranian knowledge-based companies presented their nanotechnology products in the fields of packaging of agricultural products with long durability and water purification.

As usual with something from INIC, I long for more detail, e.g., when did the visit take place?

H/t to Nanotechnology Now June 15, 2015 news item.

Seven miniature frog species in the Brazilian Atlantic Rainforest

Caption: One of the species of miniaturized frog found in the Brazilian Atlantic Forest, shows the extent of the miniaturization. Credit: Luiz Fernando Ribeiro, CC BY SA

Caption: One of the species of miniaturized frog found in the Brazilian Atlantic Forest, shows the extent of the miniaturization.
Credit: Luiz Fernando Ribeiro, CC BY SA

Seven new species of frogs, with many of them in the 1cm range as adults, have been found in the Brazilian Atlantic Rainforest. From a June 4, 2015 PeerJ news release on EurekAlert,

Following nearly 5 years of exploration in mountainous areas of the southern Brazilian Atlantic Rainforest, a team of researchers has uncovered seven new species of a highly miniaturized, brightly colored frog genus known as Brachycephalus. Each species is remarkably endemic, being restricted to cloud forests in one or a few adjacent mountaintops, thus making them highly vulnerable to extinction, particularly due to shifts in the distribution of cloud forest due to climate change.

The Atlantic Rainforest of Brazil harbors a highly unique group of frogs that have intrigued naturalists for over a century. Known as Brachycephalus, these frogs are among the smallest terrestrial vertebrates, with adult sizes often not exceeding 1 cm in length, leading to a variety of changes in their body structure, such as reduction in the number of toes and fingers. In addition, many species of Brachycephalus are brightly colored, possibly as a warning to the presence of a highly potent neurotoxin in their skin known as tetrodotoxin.

Most species of Brachycephalus are highly endemic, being found exclusively on one, or a few, adjacent mountaintops. Such high levels of endemism is caused by their adaptation to a specific kind of habitat – the cloud forests – which simultaneously prevents them from migrating across valleys and promotes the formation of new species.

The first species of Brachycephalus was described in 1842 by the famous German naturalist Johann Baptist von Spix, yet most species in the genus have been discovered only in the past decade, particularly due to their highly endemic nature and the difficulty in reaching remote montane sites. Over the course of five years of fieldwork, a team of researchers has provided the largest addition to the known diversity of Brachycephalus, with seven new species.

“Although getting to many of the field sites is exhausting, there was always the feeling of anticipation and curiosity about what new species could look like”, said Marcio Pie, a professor at the Universidade Federal do Paraná, who led the project.

Luiz Ribeiro, a research associate to the Mater Natura Institute for Environmental Studies, is optimistic about the prospects for future studies “This is only the beginning, especially given the fact that we have already found additional species that we are in the process of formally describing.”

A major concern regarding the new species is that the same factors that led to their endemism might also be a ticket to their extinction. Cloud forests are highly sensitive to climatic changes, and the long-term preservation of these species might involve not only the protection of their habitats but also more direct management efforts, such as rearing in captivity.

This is the first time I’ve come across a PeerJ news release, so here’s how they describe themselves in the release (Note: A link has been removed),

PeerJ is an Open Access publisher of peer reviewed articles, which offers researchers a lifetime publication plan, for a single low price, providing them with the ability to openly publish all future articles for free. PeerJ is based in San Francisco, CA and London, UK and can be accessed at https://peerj.com/. PeerJ’s mission is to help the world efficiently publish its knowledge.

All works published in PeerJ are Open Access and published using a Creative Commons license (CC-BY 4.0). Everything is immediately available–to read, download, redistribute, include in databases and otherwise use–without cost to anyone, anywhere, subject only to the condition that the original authors and source are properly attributed.

PeerJ has an Editorial Board of over 1,000 respected academics, including 5 Nobel Laureates. PeerJ was the recipient of the 2013 ALPSP Award for Publishing Innovation.

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

Seven new microendemic species of Brachycephalus (Anura: Brachycephalidae) from southern Brazil by Luiz F. Ribeiro, Marcos R. Bornschein, Ricardo Belmonte-Lopes, Carina R. Firkowski, Sergio A.A. Morato, & Marcio R. Pie. PeerJ 3:e1011 https://dx.doi.org/10.7717/peerj.1011 June 4, 2015

This is an open access paper.

Abakan makes good on Alberta (Canada) promise (coating for better pipeline transport of oil)

It took three years but it seems that US company Abakan Inc.’s announcement of a joint research development centre at the Northern Alberta Institute of Technology (NAIT), (mentioned here in a May 7, 2012 post [US company, Abakan, wants to get in on the Canadian oils sands market]), has borne fruit. A June 8, 2015 news item on Azonano describes the latest developments,

Abakan Inc., an emerging leader in the advanced coatings and metal formulations markets, today announced that it has begun operations at its joint-development facility in Edmonton, Alberta.

Abakan’s subsidiary, MesoCoat Inc., along with the lead project partner, Northern Alberta Institute of Technology (NAIT) will embark on an 18-month collaborative effort to establish a prototype demonstration facility for developing, testing and commercializing wear-resistant clad pipe and components. Western Economic Diversification Canada is also supporting this initiative through a $1.5 million investment toward NAIT. Improvements in wear resistance are expected to make a significant impact in reducing maintenance and downtime costs while increasing productivity in oil sands and other mining applications.

A June 4, 2015 Abakan news release, which originated the news item, provides more detail about the proposed facility, the difficulties encountered during the setup, and some interesting information about pipes,

Abakan shipped its CermaClad high-speed large-area cladding system for installation at the Northern Alberta Institute of Technology’s (NAIT) campus in Edmonton, Alberta in early 2015. Despite delays associated with the installation of some interrelated equipment and machinery, the CermaClad system and other ancillary equipment are now installed at the Edmonton facility. The Edmonton facility is intended to serve as a pilot-scale wear-resistant clad pipe manufacturing facility for the development and qualification of wear-resistant clad pipes, and as a stepping stone for setting-up a full-scale wear-resistant clad pipe manufacturing facility in Alberta. The new facility will also serve as a platform for Abakan’s introduction to the Alberta oil sands market, which, with proven reserves estimated at more than 169 billion barrels, is one of the largest oil resources in the world and a major source of oil for Canada, the United States and Asia. Since Alberta oil sands production is expected to increase significantly over the next decade, producers want to extend the life of the carbon steel pipes used for the hydro-transportation of tailings with harder, tougher coatings that protect pipes from the abrasiveness of tar-like bituminous oil sands.

“Our aim is to fast-track market entry of our wear-resistant clad pipe products for the transportation of oil sands and mining slurries. We have received commitments from oil sands producers in Canada and mining companies in Mexico and Brazil to field-test CermaClad wear-resistant clad pipe products as soon as our system is ready for testing. Apart from our work with conventional less expensive chrome carbide and the more expensive tungsten carbide wear-resistant cladding on pipes, Abakan also expects to introduce new iron-based structurally amorphous metal (SAM) alloy cladding that in testing has exhibited better performance than tungsten carbide cladding, but at a fraction of the cost.” Robert Miller stated further that “although more expensive than the more widely used chrome carbide cladding, our new alloy cladding is expected to be a significantly better value proposition when you consider an estimated life of three times that of chrome carbide cladding and those cost efficiencies that correspond to less downtime revenue losses, and lower maintenance and replacement costs.”

The costs associated with downtime and maintenance in the Alberta oil sands industry estimated at more than $10 billion a year are expected to grow as production expands, according to the Materials and Reliability in Oil Sands (MARIOS) consortium in Alberta. The development of Alberta’s oil sands has been held up by the lack of materials for transport lines and components that are resistant to the highly abrasive slurry. Due to high abrasion, the pipelines have to be rotated every three to four months and replaced every 12 to 15 months. [emphasis mine] The costs involved just in rotating and replacing the pipes is approximately $2 billion annually. The same is true of large components, for example the steel teeth on the giant electric shovels used to recover oil sands, must be replaced approximately every two days.

Abakan’s combination of high productivity coating processes and groundbreaking materials are expected to facilitate significant efficiencies associated with the extraction of these oil resources. Our proprietary materials combined with CermaClad large-area based fusion cladding technology, have demonstrated in laboratory tests a three to eight times improvement in wear and corrosion resistance when compared with traditional weld overlays at costs comparable to rubber and metal matrix composite alternatives. Abakan intends to complete development and initiate field-testing by end of year 2016 and begin the construction of a full-scale wear-resistant clad pipe manufacturing facility in Alberta in early-2017.

Given that there is extensive talk about expanding oil pipelines from Alberta to British Columbia (where I live), the information about the wear and tear is fascinating and disturbing. Emotions are high with regard to the proposed increase in oil flow to the coast as can be seen in a May 27, 2015 article by Mike Howell for the Vancouver Courier about a city hall report on the matter,

A major oil spill in Vancouver waters could potentially expose up to one million people to unsafe levels of a toxic vapour released from diluted bitumen, city council heard Wednesday in a damning city staff report on Kinder Morgan’s proposal to build a pipeline from Alberta to Burnaby [British Columbia].

In presenting the report, deputy city manager Sadhu Johnston outlined scenarios where exposure to the chemical benzene could lead to adverse health effects for residents and visitors, ranging from dizziness to nausea to possible death.

“For folks that are on the seawall, they could be actually struck with this wave of toxic gases that could render them unable to evacuate,” said Johnston, noting 25,000 residents live within 300 metres of the city’s waterfront. “These are serious health impacts. So this is not just about oil hitting shorelines, this is about our residents being exposed to very serious health effects.

  • Kinder Morgan’s own estimate is that pipeline leaks under 75 litres per hour may not be detected.

While I find the presentation’s hysteria a little off-putting, it did alert me to one or two new issues, benzene gas and when spillage from the pipes raises an alarm. For anyone curious about benzene gas and other chemical aspects of an oil spill, there’s a US National Oceanic and Atmospheric Administration (NOAA) webpage titled, Chemistry of an Oil Spill.

Getting back to the pipes, that figure of 75 litres per hour puts a new perspective on the proposed Abakan solution and it suggests that whether or not more and bigger pipes are in our future, we should do a better of job of protecting our environment now. That means better cladding for the pipes and better dispersants and remediation for water, earth, air when there’s a spill.

Evolution-in-materio and unconventional computing

Training materials such as carbon nanotubes to imitate electronic circuits? Welcome to the world of evolution-in-materio and unconventional computing. From an April 7, 2015 news item on ScienceDaily,

As we approach the miniaturization limits of conventional electronics, alternatives to silicon-based transistors — the building blocks of the multitude of electronic devices we’ve come to rely on — are being hotly pursued.

Inspired by the way living organisms have evolved in nature to perform complex tasks with remarkable ease, a group of researchers from Durham University in the U.K. and the University of São Paulo-USP in Brazil is exploring similar “evolutionary” methods to create information processing devices.

An April 7, 2015 American Institute of Physics (AIP) news release on EurekAlert, which originated the news item, delves into the research itself and the emerging field to which it belongs,

In the Journal of Applied Physics, from AIP Publishing, the group describes using single-walled carbon nanotube composites (SWCNTs) as a material in “unconventional” computing. By studying the mechanical and electrical properties of the materials, they discovered a correlation between SWCNT concentration/viscosity/conductivity and the computational capability of the composite.

“Instead of creating circuits from arrays of discrete components (transistors in digital electronics), our work takes a random disordered material and then ‘trains’ the material to produce a desired output,” said Mark K. Massey, research associate, School of Engineering and Computing Sciences at Durham University.

This emerging field of research is known as “evolution-in-materio,” a term coined by Julian Miller at the University of York in the U.K. What exactly is it? An interdisciplinary field blends together materials science, engineering and computer science. Although still in its early stages, the concept has already shown that by using an approach similar to natural evolution, materials can be trained to mimic electronic circuits–without needing to design the material structure in a specific way.

“The material we use in our work is a mixture of carbon nanotubes and polymer, which creates a complex electrical structure,” explained Massey. “When voltages (stimuli) are applied at points of the material, its electrical properties change. When the correct signals are applied to the material, it can be trained or ‘evolved’ to perform a useful function.”

While the group doesn’t expect to see their method compete with high-speed silicon computers, it could turn out to be a complementary technology. “With more research, it could lead to new techniques for making electronics devices,” he noted. The approach may find applications within the realm of “analog signal processing or low-power, low-cost devices in the future.”

Beyond pursuing the current methodology of evolution-in-materio, the next stage of the group’s research will be to investigate evolving devices as part of the material fabrication “hardware-in-the-loop” evolution. “This exciting approach could lead to further enhancements in the field of evolvable electronics,” said Massey.

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

Computing with carbon nanotubes: Optimization of threshold logic gates using disordered nanotube/polymer composites by using disordered nanotube/polymer composites by M. K. Massey, A. Kotsialos, F. Qaiser, D. A. Zeze, C. Pearson, D. Volpati, L. Bowen, and M. C. Petty. J. Appl. Phys. 117, 134903 (2015); http://dx.doi.org/10.1063/1.4915343

This paper appears to be open access.

Also, the researchers have produced a video,

Credit: Mark Massey/Durham University

Final comment, I am gobsmacked and fascinated.

Microbubbles reform into nanoparticles after bursting

It seems researchers at the Toronto-based (Canada), Princess Margaret Cancer Centre, have developed a new theranostic tool made of microbubbles used for imaging that are then burst into nanoparticles delivering therapeutics. From a March 30, 2015 news item on phys.org,

Biomedical researchers led by Dr. Gang Zheng at Princess Margaret Cancer Centre have successfully converted microbubble technology already used in diagnostic imaging into nanoparticles that stay trapped in tumours to potentially deliver targeted, therapeutic payloads.

The discovery, published online today [March 30, 2015] in Nature Nanotechnology, details how Dr. Zheng and his research team created a new type of microbubble using a compound called porphyrin – a naturally occurring pigment in nature that harvests light.

A March 30, 2015 University Health Network news release on EurekAlert, which originated the news item, describes the laboratory research on mice,

In the lab in pre-clinical experiments, the team used low-frequency ultrasound to burst the porphyrin containing bubbles and observed that they fragmented into nanoparticles. Most importantly, the nanoparticles stayed within the tumour and could be tracked using imaging.

“Our work provides the first evidence that the microbubble reforms into nanoparticles after bursting and that it also retains its intrinsic imaging properties. We have identified a new mechanism for the delivery of nanoparticles to tumours, potentially overcoming one of the biggest translational challenges of cancer nanotechnology. In addition, we have demonstrated that imaging can be used to validate and track the delivery mechanism,” says Dr. Zheng, Senior Scientist at the Princess Margaret and also Professor of Medical Biophysics at the University of Toronto.

Conventional microbubbles, on the other hand, lose all intrinsic imaging and therapeutic properties once they burst, he says, in a blink-of-an-eye process that takes only a minute or so after bubbles are infused into the bloodstream.

“So for clinicians, harnessing microbubble to nanoparticle conversion may be a powerful new tool that enhances drug delivery to tumours, prolongs tumour visualization and enables them to treat cancerous tumours with greater precision.”

For the past decade, Dr. Zheng’s research focus has been on finding novel ways to use heat, light and sound to advance multi-modality imaging and create unique, organic nanoparticle delivery platforms capable of transporting cancer therapeutics directly to tumours.

Interesting development, although I suspect there are many challenges yet to be met such as ensuring the microbubbles consistently arrive at their intended destination in sufficient mass to be effective both for imaging purposes and, later, as nanoparticles for drug delivery purposes.

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

In situ conversion of porphyrin microbubbles to nanoparticles for multimodality imaging by Elizabeth Huynh, Ben Y. C. Leung, Brandon L. Helfield, Mojdeh Shakiba, Julie-Anne Gandier, Cheng S. Jin, Emma R. Master, Brian C. Wilson, David E. Goertz, & Gang Zheng. Nature Nanotechnology (2015) doi:10.1038/nnano.2015.25 Published online 30 March 2015

This paper is behind a paywall but a free preview is available via ReadCube Access.

This is one of those times where I’m including the funding agencies and the ‘About’ portions of the news release,

The research published today was funded by the Canadian Institutes of Health Research (CIHR) Frederick Banting and Charles Best Canada Graduate Scholarship, the Emerging Team Grant on Regenerative Medicine and Nanomedicine co-funded by the CIHR and the Canadian Space Agency, the Natural Sciences and Engineering Research Council of Canada, the Ontario Institute for Cancer Research, the International Collaborative R&D Project of the Ministry of Knowledge Economy, South Korea, the Joey and Toby Tanenbaum/Brazilian Ball Chair in Prostate Cancer Research, the Canada Foundation for Innovation and The Princess Margaret Cancer Foundation.

About Princess Margaret Cancer Centre, University Health Network

The Princess Margaret Cancer Centre has achieved an international reputation as a global leader in the fight against cancer and delivering personalized cancer medicine. The Princess Margaret, one of the top five international cancer research centres, is a member of the University Health Network, which also includes Toronto General Hospital, Toronto Western Hospital and Toronto Rehabilitation Institute. All are research hospitals affiliated with the University of Toronto. For more information, go to http://www.theprincessmargaret.ca or http://www.uhn.ca .

I was not expecting to see South Korea or Brazil mentioned in the funding. Generally, when multiple countries are funding research, their own research institutions are also involved. As for the Princess Margaret Cancer Centre being one of the top five such centres internationally, I wonder how these rankings are determined.

Of airborne nanomaterials, bacterial microbiomes, viral microbiomes, and paper sensors

There’s a Jan. 14, 2015 news item on Nanowerk from the Virginia Polytechnic Institute (Virginia Tech) which is largely a personal profile featuring some basic information (useful for those new to the topic) about airborne nanoparticles (Note: A link has been removed),

The Harvard educated undergraduate [Linsey Marr,  professor of civil and environmental engineering, Virginia Tech] who obtained her Ph.D. from University of California at Berkeley and trained as a postdoctoral researcher with a Nobel laureate of chemistry at MIT is now among a handful of researchers in the world who are addressing concerns about engineered nanomaterials in the atmosphere.

Marr is part of the National Science Foundation’s Center for the Environmental Implications of Nanotechnology and her research group has characterized airborne nanoparticles at every point of their life cycle. This cycle includes production at a commercial manufacturing facility, use by consumers in the home, and disposal via incineration.

A Jan. 14, 2015 Virginia Tech news release, which originated the news item, quotes Marr on the current thinking about airborne nanoparticles,

“Results have shown that engineered nanomaterials released into the air are often aggregated with other particulate matter, such as combustion soot or ingredients in consumer spray products, and that the size of such aggregates may range from smaller than 10 nanometers to larger than 10 microns,” Marr revealed. She was referring to studies completed by research group members Marina Quadros Vance of Florianopolis, Brazil, a research scientist with the Virginia Tech Institute of Critical Technology and Applied Science, and Eric Vejerano, of Ligao, Philippines, a post-doctoral associate in civil and environmental engineering.

Size matters if these aggregates are inhaled.

Another concern is the reaction of a nanomaterial such as a fullerene with ozone at environmentally relevant concentration levels. Marr’s graduate student, Andrea Tiwari, of Mankato, Minnesota, said the resulting changes in fullerene could lead to enhanced toxicity.

The story then segues into airborne pathogens and viruses eventually honing in on virus microbiomes and bacterial microbiomes (from the news release),

Marr is a former Ironman triathlete who obviously has strong interests in what she is breathing into her own body. So it would be natural for her to expand her study of engineered nanoparticles traveling in the atmosphere to focus on airborne pathogens.

She did so by starting to consider the influenza virus as an airborne pollutant. She applied the same concepts and tools used for studying environmental contaminants and ambient aerosols to the examination of the virus.

She looked at viruses as “essentially self-assembled nanoparticles that are capable of self-replication.”

Her research team became the first to measure influenza virus concentrations in ambient air in a children’s day care center and on airplanes. When they conducted their studies, the Virginia Tech researchers collected samples from a waiting room of a health care center, two toddlers’ rooms and one babies’ area of a childcare center, as well as three cross-country flights between Roanoke, Virginia., and San Francisco. They collected 16 samples between Dec. 10, 2009 and Apr. 22, 2010.

“Half of the samples were confirmed to contain aerosolized influenza A viruses,” Marr said. The childcare samples were the most infected at 75 percent. Next, airplane samples reached 67 percent contamination, and health center numbers came in at 33 percent.

This study serves as a foundation for new work started about a year ago in her lab.

Marr collaborated with Aaron J. Prussin II, of Blacksburg, Virginia, and they successfully secured for him a postdoctoral fellowship from the Alfred P. Sloan Foundation to characterize the bacterial and viral microbiome — the ecological community of microorganisms — of the air in a daycare center.

They are now attempting to determine seasonal changes of both the viral microbiome and the bacterial microbiome in a daycare setting, and examine how changes in the microbiome are related to naturally occurring changes in the indoor environment.

“Little is known about the viral component of the microbiome and it is important because viruses are approximately 10 times more abundant than bacteria, and they help shape the bacterial community. Research suggests that viruses do have both beneficial and harmful interactions with bacteria,” Prussin said.

With Prussin and Marr working together they hope to verify their hypothesis that daycare centers harbor unique, dynamic microbiomes with plentiful bacteria and viruses. They are also looking at what seasonal changes might bring to a daycare setting.

They pointed to the effect of seasonal changes because in previous work, Marr, her former graduate student Wan Yang, of Shantou, China, and Elankumaran Subbiah, a virologist in the biomedical sciences and pathobiology department of the Virginia-Maryland College of Veterinary Medicine, measured the influenza A virus survival rate at various levels of humidity.

Their 2012 study presented for the first time the relationship between the influenza A virus viability in human mucus and humidity over a large range of relative humidities, from 17 percent to 100 percent. They found the viability of the virus was highest when the relative humidity was either close to 100 percent or below 50 percent. The results in human mucus may help explain influenza’s seasonality in different regions.

According to the news release Marr and her colleagues have developed a fast and cheap technology for detection of airborne pathogens (Note: A link has been removed),

With the urgent need to understand the dynamics of airborne pathogens, especially as one considers the threats of bioterrorism, pandemic influenza, and other emerging infectious diseases, Marr said “a breakthrough technology is required to enable rapid, low-cost detection of pathogens in air.”

Along with Subbiah and Peter Vikesland,  professor of civil and environmental engineering, they want to develop readily deployable, inexpensive, paper-based sensors for airborne pathogen detection.

In 2013 they received funding of almost $250,000 from Virginia Tech’s Institute for Critical Technology and Applied Science, a supporter of the clustering of research groups, to support their idea of creating paper-based sensors based on their various successes to date.

Marr explained the sensors “would use a sandwich approach. The bottom layer is paper containing specialized DNA that will immobilize the virus. The middle layer is the virus, which sticks to the specialized DNA on the bottom layer. The top layer is additional specialized DNA that sticks to the virus. This DNA is attached to gold nanoparticles that are easily detectable using a technique known as Raman microscopy.”

They key to their approach is that it combines high-tech with low-tech in the hopes of keeping the assay costs low. Their sampling method will use a bicycle pump, and low cost paper substrates. They hope that they will be able to incorporate smart-phone based signal transduction for the detection. Using this approach, they believe “even remote corners of the world” would be able to use the technique.

Vikesland previously received funding from the Gates Foundation to detect the polio virus via paper-based diagnostics. Polio is still found in countries on the continents of Asia and Africa.

I have previously mentioned Linsey Marr in an Oct. 18, 2013 post about the revival of the Nanotechnology Consumer Products Inventory (originally developed by the Project for Emerging Nanotechnologies) by academics at Virginia Tech and first mentioned CEINT in an Aug. 15, 2011 post about a special project featuring a mesocosm at Duke University (North Carolina).

TED Global would like to see you in Rio—USD $6,000 + application required

TED (technology, entertainment, design) Global is being held in Rio de Janeiro, Brazil in October 2014 and there are still a few spots left for participants according to a July 23, 2014 notice (I checked here, there are still openings as of Aug. 1, 2014),

In early October, Rio de Janeiro will host our first TEDGlobal in South America. The conference theme is “South” and you can meet here. Held in the historic Copacabana Palace Hotel on the eponymous beach, TEDGlobal 2014 promises speakers with amazing new ideas to stimulate your mind, while the rest of you takes in the beauty that is Rio: the ocean, the beach, the volcanic mountains, and the energetic Cariocas. It is simply one of the most beautiful cities on Earth.

We hope you will join us at this more intimately scaled event (half the size of TED in Vancouver), and celebrate ideas from across the Global South.

The conference takes place October 5-10, 2014. During five immersive days of talks, music, performances, tech demos, exhibits and wonderful parties, the conference will focus on the Global South’s rise in influence and power — plus relevant stories from the rest of the world.

A small number of passes remain for $6,000 and $12,000. …

Questions? Email registration@ted.com.

Vê-lo no Rio (See you in Rio)

There is a list of their currently confirmed speakers here. It includes:

Grimanesa Amoros, Peruvian interdisciplinary artist

Séverine Autesserre, Congo scholar
Tasso Azevedo, Brazilian forest conservationist
Rodrigo Baggio, Brazilian digital inclusionist
Khalida Brohi, Pakistani equality activist

Wendy Freedman, Astronomer

Syed Karim, Satellite datacaster
...
Miguel Nicolelis, Brain interface pioneer

Mark Plotkin, Amazonian ethnobotanist

Matthieu Ricard, Buddhist monk

Steve Song, Africa connectivity tinkerer
Jorge Soto, Cancer detection technologist

Zeynep Tufekci, Technosociologist

Tashka Yawanawa, Amazonian chief

I recognized two names on the full list: Miguel Nicolelis (featured here many times and most recently in a May 20, 2014 posting) and Matthieu Ricard (mentioned here once.in an April 11, 2013 posting). Both of them were mentioned in regard to the field of neuroscience.

On that note, Happy Weekend on what is a long weekend for many Canadians including me!

Canadian government spending on science and technology is down for the fourth year in a row

It seems there a steady downward trajectory where Canadian science and technology spending is concerned. Stephen Hui in a May 28, 2014 article for the Georgia Straight, breaks the latest news from Statistics Canada (Note: A link has been removed),

The Canadian government is expected to spend less money on science and technology in 2014-15 compared to the previous fiscal year, continuing a trend that began in 2011-12. [emphasis mine]

According to Statistics Canada, federal departments and agencies are projected to record $10.3 billion (all figures in current dollars) in science and tech expenditures in 2014-15, a decrease of 5.4 percent from 2013-14.

Federal science and tech spending peaked at $12 billion in 2010-11 and has declined every year since then.

In fact, an earlier July 30, 2013 news item in Huffington Post noted a decrease in the 2013-14 budget,

The federal agency says spending for the 2013-14 fiscal year is expected to decrease 3.3 per cent from the previous period, to $10.5 billion.

It adds research and development is expected to account for two-thirds of anticipated science and technology spending.

The finding is contained in Statistics Canada’s annual survey of all federal government departments and agencies believed to be performing or funding science and technology activities.

The survey, released Tuesday [July 2013], covers the period from Sept. 10, 2012 to Jan. 11, 2013.

Statistics Canada says spending on science and technology has been steadily decreasing since 2009-10. [emphasis mine]

According to Hui’s source, the Statistics Canada’s The Daily, May 28,2014: Federal government spending on science and technology, 2014/2015, the trend started in 2011/12. I’m not sure which specific Statistics Canada publication was the source for the Huffington Post’s start date for the decline.

Interestingly, the OECD (Organization for Economic Cooperation and Development) Science, Technology and Industry Scoreboard 2013 dates the decline to 2001. From my Oct. 30, 2013 posting (excerpted from the scorecard),

Canada is among the few OECD countries where R&D expenditure declined between 2000 and 2011 (Figure 1). This decline was mainly due to reduced business spending on R&D. It occurred despite relatively generous public support for business R&D, primarily through tax incentives. In 2011, Canada was amongst the OECD countries with the most generous tax support for R&D and the country with the largest share of government funding for business R&D being accounted for by tax credits (Figure 2). …

If I understand this rightly, Canadian business spending on R&D has been steadily declining for more than a decade and, since 2010 or so, Canadian government spending is also steadily declining. Does anyone else see this as a problem?

The contrast with Brazil is startling. From a June 2, 2014 Institute of Physics news release (also on EurekAlert but dated as June 1, 2014),

As Brazil gets set to host the 2014 FIFA World Cup this month amid concerns about the amount of public money being used to stage the world’s largest sporting event, Physics World‘s editorial team reveals in a new special report how physicists are taking full advantage of the four-fold increase in science funding that the government has invested over the past 10 years.

Since this news comes from the physics community, the news release focuses on physics-related developments,

Negotiations are currently under way to make Brazil an associate member of the CERN particle-physics lab in Geneva, while the country is also taking a leading role in the Pierre Auger Observatory – an international project based in Argentina designed to study ultrahigh-energy cosmic rays. [emphasis mine]

Building is also under way to create a world-leading synchrotron source, Sirius and Brazil is poised to become the first non-European member of the European Southern Observatory.

Carlos Henrique de Brito Cruz, a physicist at the University of Campinas and scientific director at FAPESP – one of Brazil’s most important funding agencies – told Physics World that the expectation is for Brazilian scientists to take a leadership role in such large research projects “and not just watch as mere participants”.

Considering the first graduate programmes in physics did not emerge in Brazilian universities until 1960, the rise to becoming one of the leading participants in international collaborations has been a rapid one.

The reputation of Brazilian physics has grown in line with a massive increase in science funding, which rose from R$12bn (about £3bn) in 2000 to R$50bn (around £13bn) in 2011.

Brazil’s spending on R&D now accounts for 1.2% of the gross domestic product and 40% of the total funding comes from companies.

The Brazilian Physical Society has around 6000 members comprising almost all research physicists in the country, who wrote around 25 000 research articles in international science journals between 2007 and 2010.

A lack of funding in the past had forced Brazilian scientists to focus on cheaper, theoretical research, but this has now changed and there is an almost even split between theory and experiment at universities.

Yet Brazil still suffers from several long-standing problems, the most significant being the poor standard of science education in high schools. A combination of low pay and lack of recognition makes physics teaching an unpopular choice of occupation despite attempts to tackle the problem.

Even those students who do see physics as a career option end up struggling and under-prepared for the rigours of an undergraduate physics course. Vitor de Souza, an astrophysicist at the Physics Institute at São Carlos, which is part of the University of São Paulo, told Physics World that of the 120 students who start a four-year physics degree at his university, only 10-20 actually graduate.

Another problem in Brazil is a fundamental disconnect between academic research and industrial development, with universities not sure how to handle spin-off firms and companies suspicious of universities.

More broadly, physicists feel that Brazilian society does not recognize the value of science, and that this can only be overcome when the physics community becomes more ambitious and more audacious.

You can find the special issue of Physics World here (it is open access).

As I noted in this May 30, 2014 posting (and elsewhere) featuring the new Agency of Science Communication, Technology and Innovation of Argentina (ACCTINA),,

The PCST [13th International Public Communication of Science and Technology Conference] international conference takes place every two years. The 2014 PCST conference took place in Salvador, Brazil. Conferences like this would seem to confirm the comments I made in a May 20, 2014 posting,

Returning to 2014, the [World Cup {soccer}] kickoff in Brazil (if successful) symbolizes more than an international athletic competition or a technical/medical achievement, this kick-off symbolizes a technological future for Brazil and its place on the world stage (despite the protests and social unrest) .

While the science and technology community in Brazil has its concerns, I imagine most Canadian scientists would thrill to being the recipients of the funding bonanza of 1.2%  of the gross domestic product. According to the Conference Board of Canada, research and development spending in Canada was 0.8% of GDP for 2011 (from the Conference Board of Canada’s Public R&D spending webpage),

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Did you notice, Canada the in 2011 was on the edge of getting a C grade along with the US? Meanwhile, if Brazil was listed, it would get top marks.

The question as to how much money is not enough for research and development (R&D) spending is complex and I don’t think it’s easily answered but it would be nice to see some discussion.