Posts Tagged ‘University of Toronto’

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University of Toronto’s (Canada) smiley face tattoo/sensor

Tuesday, December 4th, 2012

Researchers at the University of Toronto have created a medical sensor that can be applied to the skin like a temporary tattoo.

University of Toronto Scarborough student Vinci Hung helped create the smiley face sensor shown here in the box at upper right (photo by Ken Jones)

The Dec. 3, 2012 news item on ScienceDaily notes,

A medical sensor that attaches to the skin like a temporary tattoo could make it easier for doctors to detect metabolic problems in patients and for coaches to fine-tune athletes’ training routines. And the entire sensor comes in a thin, flexible package shaped like a smiley face.

“We wanted a design that could conceal the electrodes,” says Vinci Hung, a PhD candidate in the Department of Physical & Environmental Sciences at UTSC [University of Toronto Scarborough], who helped create the new sensor. “We also wanted to showcase the variety of designs that can be accomplished with this fabrication technique.”

The Dec. 3, 2012 University of Toronto news release by Kurt Kleiner, which originated the news item, provides details about how the sensor/tattoo is fabricated and how it functions on the skin,

The new tattoo-based solid-contact ion-selective electrode (ISE) is made using standard screen printing techniques and commercially available transfer tattoo paper, the same kind of paper that usually carries tattoos of Spiderman or Disney princesses. In the case of the smiley face sensor, the “eyes” function as the working and reference electrodes, and the “ears” are contacts to which a measurement device can connect.

…

The sensor Hung helped make can detect changes in the skin’s pH levels in response to metabolic stress from exertion. Similar devices, called ion-selective electrodes (ISEs), are already used by medical researchers and athletic trainers. They can give clues to underlying metabolic diseases such as Addison’s disease, or simply signal whether an athlete is fatigued or dehydrated during training. The devices are also useful in the cosmetics industry for monitoring skin secretions.

But existing devices can be bulky, or hard to keep adhered to sweating skin. The new tattoo-based sensor stayed in place during tests, and continued to work even when the people wearing them were exercising and sweating extensively. The tattoos were applied in a similar way to regular transfer tattoos, right down to using a paper towel soaked in warm water to remove the base paper.

To make the sensors, Hung and her colleagues used a standard screen printer to lay down consecutive layers of silver, carbon fibre-modified carbon and insulator inks, followed by electropolymerization of aniline to complete the sensing surface.

By using different sensing materials, the tattoos can also be modified to detect other components of sweat, such as sodium, potassium or magnesium, all of which are of potential interest to researchers in medicine and cosmetology.

You can find the reserchers’ article in the Royal Society’s Analyst journal,

Tattoo-based potentiometric ion-selective sensors for epidermal pH monitoring
Amay J. Bandodkar ,  Vinci W. S. Hung ,  Wenzhao Jia ,  Gabriela Valdés-Ramírez ,  Joshua R. Windmiller ,  Alexandra G. Martinez ,  Julian Ramírez ,  Garrett Chan ,  Kagan Kerman and Joseph Wang in Analyst, 2013,138, 123-128 DOI: 10.1039/C2AN36422K

The article is open access but you do need to register for a free account with the Royal Society’s RSC [ublishing platform.

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Posted in medicine | 1 Comment »

Revising the view on genomes: mouse and human

Friday, October 5th, 2012

Researchers in Canada and the US have resolved a question about DNA and structural protein. From the Oct. 4, 2012 news release on EurekAlert,

Scientists in Canada and the United States have used three-dimensional imaging techniques to settle a long-standing debate about how DNA and structural proteins are packaged into chromatin fibres. The researchers, whose findings are published in EMBO [European Molecular Biology Organization] reports, reveal that the mouse genome consists of 10-nm chromatin fibres but did not find evidence for the wider 30-nm fibres that were previously thought to be important components of the DNA architecture.

Scientists were trying to understand how DNA can be packed into a cell,

“DNA is an exceptionally long molecule that can reach several metres in length. This means it needs to be packaged into a highly compact state to fit within the limited space of the cell nucleus,” said David Bazett-Jones, Senior Scientist at the Hospital for Sick Children, Toronto, and Professor at the University of Toronto, Canada. “For the past few decades, scientists have favoured structural models for chromatin organization where DNA is first wrapped around proteins in nucleosomes. In one possible model, the strand of repeating nucleosomes is wrapped further into a higher-order thick 30-nm fibre. In a second model, the 30-nm fibre is not required to compact the DNA. Differences between these models have implications for the way the cell regulates the transcription of genes.”

Scientists offer reasons for why they concluded Previous studies have suggested for a 30-nm fibre model in earlier studies,

The researchers offer several reasons for the observation of wider fibres in earlier studies. In some cases, the conditions outside of the cell, including those used in earlier studies where chromatin was extracted from the cell, may have given rise to structural artifacts. For some of the earlier spectroscopic studies, it may even be a question of poor resolution of existing 10-nm fibres.

Here’s what the scientists found,

“Our results revealed that the 30-nm chromatin fibre model is not consistent with the structure we found in our three-dimensional spectroscopic images,” said Bazett-Jones. “It was previously thought that the transition between thinner and thicker fibres represented a change from an active to repressed state of chromatin. However, our inability to detect 30-nm fibres in the mouse genome leads us to conclude that the transcriptional machinery has widespread access to the DNA packaged into chromatin fibres.”

The results are consistent with recent studies of the human genome which suggest that approximately 80% of the genome contains elements that are linked to biological function. Access to enhancers, promoters and other regulatory sequences on such a wide region of the genome means that all of these sites must be accessible. The 10-nm model of chromatin fibres provides sufficient access to DNA to allow potential target sites to be reached. The 30-nm model would not accommodate such widespread access.

You can read more about the research both in the EurekAlert news release or in the Oct. 5, 2012 news itemon Azonano. Or, you can read the article, Open and closed domains in the mouse genome are configured as 10-nm chromatin fibres, if you can get behind the paywall.

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Posted in medicine, nanotechnology | No Comments »

Precision delivery of synthetic vaccines using DNA scaffolds

Tuesday, August 7th, 2012

When reading about nanomedicine, one is struck by the focus on precision especially with the regard to drug delivery and other therapeutics. There’s almost always a reference to repairing or destroying  malfunctioning/diseased tissue or cells to the exclusion of the  healthy tissues/cells.

The latest work from Arizona State University has raised a great deal of interest not just with this latest announcement but also some previous work. From the July 27, 2012 posting by Dexter Johnson on his Nanoclast blog on the IEEE [Institute for Electrical and Electronics Engineers],

About 18 months ago, the nanotech trade press was buzzing with the work of Hongbin Yu and Hao Yan, both from Arizona State University (ASU), when they developed a method that used DNA origami as a scaffold. When the DNA scaffolding was combined with “nano islands” made from gold, it enabled the manufacturing of smaller electronic memory devices.

Now [July 2012] Yan has joined with Yung Chang, a biodesign immunologist also from ASU, to use three-dimensional DNA structures as a scaffold on which they piggybacked synthetic vaccine complexes to make the delivery of the vaccines safer and more effective.

There are more details in the July 25, 2012 news item on ScienceDaily,

DNA nanotechnology, where the molecule of life can be assembled into 2-D and 3-D shapes, has an advantage of being a programmable system that can precisely organize molecules to mimic the actions of natural molecules in the body.

“We wanted to test several different sizes and shapes of DNA nanostructures and attach molecules to them to see if they could trigger an immune response,” said Yan, the Milton D. Glick Distinguished Chair in the Department of Chemistry and Biochemistry and researcher in Biodesign’s Center for Single Molecule Biophysics. With their biomimicry approach, the vaccine complexes they tested closely resembled natural viral particles in size and shape.

As proof of concept, they tethered onto separate pyramid-shaped and branched DNA structures a model immune stimulating protein called streptavidin (STV) and immune response boosting compound called an adjuvant (CpG oligo-deoxynucletides) to make their synthetic vaccine complexes.

First, the group had to prove that the target cells could gobble the nanostructures up. By attaching a light-emitting tracer molecule to the nanostructures, they found the nanostructures residing comfortably within the appropriate compartment of the cells and stable for several hours — -long enough to set in motion an immune cascade.

Next, in a mouse challenge, they targeted the delivery of their vaccine cargo to cells that are first responders in initiating an effective immune response, coordinating interaction of important components, such as: antigen presenting cells, including macrophages, dendritic cells and B cells. After the cargo is internalized in the cell, they are processed and “displayed” on the cell surface to T cells, white blood cells that play a central role in triggering a protective immune response. The T cells, in turn, assist B cells with producing antibodies against a target antigen.

To properly test all variables, they injected: 1) the full vaccine complex 2) STV (antigen) alone 3) the CpG (adjuvant) mixed with STV.

Over the course of 70 days, the group found that mice immunized with the full vaccine complex developed a more robust immune response up to 9-fold higher than the CpG mixed with STV. The pyramid (tetrahedral) shaped structure generated the greatest immune response. Not only was immune response to the vaccine complex specific and effective, but also safe, as the research team showed, using two independent methods, that no immune response triggered from introducing the DNA platform alone.

Here’s a little background information that may help to explain why researchers are looking for new ways to deliver vaccines, from the July 30, 2012 essay by Carl Walkey (University of Toronto) for the Nanowerk Spotlight series,

Traditionally, vaccines were formulated using attenuated or inactivated versions of the microbes they were intended to treat. However, inactivated microbes do not often elicit a strong enough immune response to induce antibody production. Attenuated viruses, on the other hand, may revert back to an active form within the body. There are also inherent difficulties in ensuring batch-to-batch consistency of the formulations. These shortcomings have led to a progressive shift towards the development of synthetic vaccines.

Synthetic vaccines can combine a portion of the target microbe, known as an ‘antigen’ together with an adjuvant that stimulates the immune system. They are more reproducible and have the potential to induce consistent and tailored immune responses. Yet, delivering both the adjuvant and antigen together to the appropriate immune cells is challenging.

While the developments at Arizona State University are exciting, it’s still a long way before there will be any treatments, from the Walkey essay,

Although the results from this study are encouraging, they represent only a step towards the ultimate goal of making DNA nanostructure-based vaccines a clinical reality. There are still many challenges.

“A big challenge from an immunological point of view is the stability of the particles” explains Chang. The body is equipped with an array of ‘nucleases’ – enzymes designed to degrade extracellular DNA. Nucleases may degrade the nanostructures before they reach their target.”

“I think safety will also be a major hurdle for the eventual clinical translation” he continues. “That will be the major concern people will have. It may cause an adverse effect or an auto-immune response. Those are the things we need to test thoroughly before moving into clinical trials.”

The researchers believe that the simplicity, robustness, and relative economy of the DNA nanostructures will be key advantages driving further development.

“DNA nanostructures have the advantage of self-assembling. You can produce them relatively simply with good reproducibility” says Yan. “With so many of the other nanoparticle systems, you have to synthesize different components chemically. This makes them difficult to scale-up.”

The July 24, 2012 news release from Arizona State University offers this comment on the potential,

Overall, though the field of DNA is still young, the research is advancing at a breakneck pace toward translational science that is making an impact on health care, electronics, and other applications.

While Chang and Yan agree that there is still much room to explore the manipulation and optimization of the nanotechnology, it also holds great promise.  “With this proof of concept, the range of antigens that we could use for synthetic vaccine develop is really unlimited,” said Chang.

I like the idea of more precise delivery of drugs and other therapies. Intuitively, it just makes sense that you want to focus on the diseased or destroyed tissues while preserving as much of the healthy ones as possible but I keep wondering if there might be a more subtle disease process at work. The problem may not lie in the diseased cells or tissues themselves but may originate in an entirely different part of the body. If you ever watch someone who’s walking awkwardly, you may notice the problem isn’t the foot placement; the real problem is in the hips. You are in fact examining the symptom rather than the problem. In which case, more precise application of various therapies will alleviate symptoms for a time while the disease process carries on.

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Environment influences nanomaterial reactions to biological cells

Tuesday, July 31st, 2012

The discussion I’ve seen around nanomaterials and toxicological effects has largely centered on shapes, size, aggregate/agglomerate, etc. By contrast, Carl Walkey’s July 24, 2012 Nanowerk Spotlight essay focuses on nanomaterial surfaces, bare or coated with serum proteins (Note: I have removed links),

Biomolecule adsorption to nanomaterials is usually studied from physiological fluids with suspended biomolecules. Examples include blood serum/plasma, pulmonary surfactant, and synovial fluid. However, until now the amount of those molecules has not been considered relevant to the study. In a recent article appearing in ACS Nano (“Effects of the Presence or Absence of a Protein Corona on Silica Nanoparticle Uptake and Impact on Cells”), Drs. Anna Salvati, Kenneth Dawson, and their colleagues at the University College in Dublin, Ireland, show that if nanoparticles are exposed directly to cells in the absence of suspended biomolecules, the nanoparticles will extract biomolecules directly from cells themselves.

In their experiments, the team exposed silica nanoparticles to cells in two sets. One set was introduced into cell culture media that was supplemented with the usual concentration of fetal bovine serum, and the other into media that had no serum additives. They then incubated both sets of particles with a lung cancer cell line and measured particle uptake kinetics and cell adhesion. Nanoparticles treated under both conditions associated with cells. However, the particles that were incubated in media alone associated to a much greater extent than those that were first incubated in serum. This indicates that the affinity of the bare nanoparticle surface to the cell is much higher than the affinity of an equivalent surface that is coated with serum proteins. [emphasis mine] Similar observations are reported before for other systems, where it was also found that uptake under serum-free conditions is higher.

Moe specifically,

“When the nanomaterial is put in contact with a physiological environment, it is given a menu of possible biomolecules to adsorb” explains Dawson. “It will essentially go shopping for the biomolecules that it wants. Over time, it will exchange with the environment until it finds the things that it really likes most. If you don’t give it enough biomolecules in the form of serum, it will extract components from the cells themselves.”

The same silica nanoparticles exposed to cells in the two different conditions had different cellular responses as well. Most of the serum-coated particles were taken up within vesicles in the cell cytoplasm and produced no overt signs of toxicity. In contrast, the particles without a serum coating adhered to the cell surface to a greater extent, were present in vesicles, and some were also found free-floating in the cytoplasm. Exposure to particles in absence of serum significantly decreased cell viability and caused cells to take on a rounded morphology that is indicative of cell death. Dawson believes that cell death from uncoated particles is the result of strong interactions between the particle surface and the cell surface, which may damage the cell membrane, and/or initiate aberrant signaling cascades. When serum proteins are adsorbed to the nanoparticles, they ‘passivate’ the surface and limit direct nanomaterial-cell interactions.

When considering the early interactions of a nanomaterial with a cell, Dawson points out that one cannot think of the nanomaterial alone. Instead, one must think of the nanoparticle and its adsorbed biomolecules as a fundamental unit. [emphasis mine]

Most importantly,

Dawson believes that researchers must pay closer attention to the composition of the biomolecular environment surrounding the particles and cells when performing in vitro experiments. In other words, it is as important to consider the composition of the biomolecules in the media as it is to consider the chemical nature of the nanoparticle and the cell type. [emphasis mine]

“What’s absolutely clear is that depending on the type of dispersion that you make up, whether you add 10% serum or 20% serum, you get different levels of cell uptake” says Dawson. “Indeed, you get different levels of damage as well. It is therefore not meaningful to say that the nanoparticle is or is not toxic in that simplistic way. You can make a material toxic if you really want to make it toxic. You can make many materials damage cells simply because these have high surface energy. However, in a realistic physiological environment, part of the particle surface is covered and so that kind of damage would not be applicable.”

I encourage anyone who’s interested in nanotoxicology to read Walkey’s essay in full as I’ve excerpted only a portion.

BTW, Carl Walkey is a PhD graduate student at the University of Toronto and a member of the Integrated Nanotechnology & Biomedical Sciences Laboratory (INBS). I last mentioned Walkey in my July 12, 2012 posting about his Nanowerk Spotlight essay on nanotoxicology and animal studies.

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Posted in nanotechnology, risk | No Comments »

Colloidal quantum dot film from the University of Toronto and KAUST certified world’s most efficient

Monday, July 30th, 2012

In my Sept. 20, 2011 posting, I featured an item about Ted Sargent ‘s (University of Toronto, Canada) work on colloidal quantum dot films. These films have now been certified as the world’s most efficient. There seems to be a lot of excitement given that these films have achieved a 7% efficiency rating. From the July 30, 2012 news item by Will Soutter on Azonano,

A team of scientists from the King Abdullah University of Science & Technology (KAUST) and University of Toronto (U of T) headed by Ted Sargent, an U of T Engineering Professor, has achieved a significant progress in the advancement of colloidal quantum dot (CQD) films, which in turn results in a CQD solar cell with an unprecedented efficiency of 7%.

The July 30, 2012 news release from the University of Toronto provides more detail,

“Previously, quantum dot solar cells have been limited by the large internal surface areas of the nanoparticles in the film, which made extracting electricity difficult,” said Dr. Susanna Thon, a lead co-author of the paper. “Our breakthrough was to use a combination of organic and inorganic chemistry to completely cover all of the exposed surfaces.”

…

The U of T cell represents a 37% increase in efficiency over the previous certified record. In order to improve efficiency, the researchers needed a way to both reduce the number of “traps” for electrons associated with poor surface quality while simultaneously ensuring their films were very dense to absorb as much light as possible. The solution was a so-called “hybrid passivation” scheme.

“By introducing small chlorine atoms immediately after synthesizing the dots, we’re able to patch the previously unreachable nooks and crannies that lead to electron traps,” explained doctoral student and lead co-author Alex Ip. “We follow that by using short organic linkers to bind quantum dots in the film closer together.”

Work led by Professor Aram Amassian of KAUST showed that the organic ligand exchange was necessary to achieve the densest film.

“The KAUST group used state-of-the-art synchrotron methods with sub-nanometer resolution to discern the structure of the films and prove that the hybrid passivation method led to the densest films with the closest-packed nanoparticles,” stated Professor Amassian.

I think the excitement over 7% indicates just how much hard work the researchers have accomplished to achieve this efficiency. It reminds me of reading about the early development of electricity (Power struggles; Scientific authority and the creation of practical electricity before Edison by Michael Brian Schiffer)  where accomplishments we would now consider minuscule built careers.

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Posted in energy, nanotechnology | 2 Comments »

Free the rats, mice, and zebrafish from the labs—replace them with in vitro assays to test nanomaterial toxcicity

Thursday, July 12th, 2012

The July 9, 2012 Nanowerk Spotlight article by Carl Walkey (of the University of Toronto) focuses on research by Dr. André Nel and his coworkers at the California NanoSystems Institute (CNSI) and the University of California Los Angeles (UCLA) on replacing small animal model testing for nanomaterial toxicity with in vitro assays,

Currently, small animal models are the ‘gold standard’ for nanomaterial toxicity testing. In a typical assessment, researchers introduce a nanomaterial into a series of laboratory animals, generally rats or mice, or the ‘workhorse’ of toxicity testing – zebrafish (see: “High content screening of zebrafish greatly speeds up nanoparticle hazard assessment”). They then examine where the material accumulates, whether it is excreted or retained in the animal, and the effect it has on tissue and organ function. A detailed understanding often requires dozens of animals and can take many months to complete for a single formulation. The current infrastructure and funding for animal testing is insufficient to support the evaluation of all nanomaterials currently in existence, let alone those that will be developed in the near future. This is creating a growing deficit in our understanding of nanomaterial toxicity, which fuels public apprehension towards nanotechnology.

Dr. André Nel and his coworkers at the California NanoSystems Institute (CNSI) and the University of California Los Angeles (UCLA) are taking a fundamentally different approach to nanomaterial toxicity testing.

Nel believes that, under the right circumstances, resource-intensive animal experiments can be replaced with comparatively simple in vitro assays.  The in vitro assays are not only less costly, but they can also be performed using high throughput (HT) techniques. By using an in vitro HT screening approach, comprehensive toxicological testing of a nanomaterial can be performed in a matter of days. Rapid information gathering will allow stakeholders to make rational, informed decisions about nanomaterials during all phases of the development process, from design to deployment.

I’ve excerpted a brief description of Nel’s approach,

Rather than using in vitro systems as direct substitutes for the in vivo case, Nel is using a mechanistic approach to connect cellular responses to more complex biological responses, attempting to employ mechanisms that are engaged at both levels and reflective of specific nanomaterial properties.

“You need to align what you test at a cellular level with what you want to know at the in vivo” says Nel. “If oxidative stress at the cellular level is a key initiating element, then by screening for this outcome in cells you more are likely to yield something more predictive of the in vivo outcome. We can do a lot of our mechanistic work at an implementation level that allows development of predictive screening assays.”

By measuring many relevant mechanistic responses, and integrating the results, Nel believes that the in vivo behavior of a nanomaterial can be accurately predicted, provided that enough thinking goes into the devising the systems biology approach to safety assessment.

According to Walkey’s article, this approach could result in a ‘reverse’ nanomaterial development process,

Nel’s approach will influence not only the way in which nanomaterial toxicity is assessed, but also the way in which nanomaterials are developed. Currently, nanomaterials are designed to meet the need of a particular application. Toxicity is then evaluated retrospectively. Formulations that exhibit unacceptable toxicity at that point may be abandoned after a significant investment in development. Because Nel’s approach generates toxicity information much faster than traditional techniques, it will be possible to integrate toxicity during the design of a new nanomaterial. The proactive characterization of nanomaterial toxicity will provide feedback during the design process, producing formulations that maximize efficacy and minimize risk.

This is a very interesting article (illustrated with images and peppered with accessibly explanations of the issues) for anyone following the ‘nanomaterial toxicology’ story.

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Posted in nanotechnology, risk | 1 Comment »

Folding screens at University of Toronto and EPD (electronic paper display) with LG

Tuesday, April 3rd, 2012

University of Toronto researchers recently announced a breakthrough with regard to organic light-emitting diodes (OLEDs) and flexible screens. From the March 29, 2012 news item by Allyson Rowley on physorg.com,

Michael Helander and Zhibin Wang, PhD candidates in the Faculty of Applied Science and Engineering, are members of a research team that has developed the world’s most efficient organic light-emitting diodes (OLEDs) on flexible plastic. Good news for manufacturers and consumers alike, the discovery means a less costly, more efficient and environmentally friendly way to build brighter flat-panel displays on a thinner, more durable and flexible surface.

…

The students had been cleaning sheets of indium tin oxide – a material used in all flat-panel displays – when they noticed that devices built using their cleaned sheets had become much more efficient than expected, using less energy to achieve much higher brightness. After some investigation, they determined that this greater efficiency was the result of molecules of chlorine picked up from their cleaning solvent. With this surprising discovery, the two students engineered a prototype for a new kind of OLED device, which is both simpler in construction and more efficient.

According to Rowley’s University of Toronto March 26, 2012 news release,

Over time, though, OLED devices became more complex – the original two layers of molecules became many layers, which raised manufacturing costs and failure rates.

“Basically, we went back to the original idea – and started again,” said Wang. The team’s findings were published, and in December, Helander and Wang, together with Lu [ Professor Zheng-Hong Lu.who supervises both Helander and Wang] and another U of T grad student, launched OTI Lumionics, a startup that will take the next steps toward commercializing the technology.

While OTI Lumionics is taking its next steps, the company, LG Display based in Korea has announced production of a plastic electronic paper display (EPD). From the March 30, 2012 news item by Nancy Owano on physorg.com,

LG Display has set the production clock ticking for a plastic EPD (electronic paper display) product which in turn is expected to set e-book marketability fast-forward. In an announcement Thursday, Korea-based LG Display, which manufactures thin film transistor liquid crystal display, said it has already started up mass production of EPD for e-books.

Amar Toor’s March 29, 2012 item for engadget features the company’s news release, as well as, this detail,

The plan going forward is to supply the display to ODMs [original design manufacturer] in China, in the hopes of bringing final products to Europe by “the beginning of next month.” [May 2012?]

Apparently, the screen resolution is 1024 x 768 and it has a range of 40 degrees when bent from the centre.

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Posted in New Media | 1 Comment »

Greener catalysts with iron nanoparticles

Wednesday, March 28th, 2012

A research team at the University of Toronto has announced the discovery of a possible ‘green’ alternative to commonly used catalysts in the food, drug, and fragrance industries. From the March 27, 2012 news item on Nanowerk,

A chemistry team at the University of Toronto has discovered environmentally-friendly iron-based nanoparticle catalysts that work as well as the expensive, toxic, metal-based catalysts that are currently in wide use by the drug, fragrance and food industry.

“It is always important to strive to make industrial syntheses more green, and using iron catalysts is not only much less toxic, but it is also much more cost effective,” said Jessica Sonnenberg, a PhD student and lead author of a paper published this week in the Journal of the American Chemical Society (“Iron Nanoparticles Catalyzing the Asymmetric Transfer Hydrogenation of Ketones”).

The March 27, 2012 University of Toronto news release provides a quote from Sonnenberg which suggests there’s still a lot more work to be done before the toxic metal-based catalysts currently being used could be replaced,

… “Catalysts, even cheap iron ones developed for these types of reaction, still suffer one major downfall,” explained Sonnenberg.  “They require a one-to-one ratio of very expensive organic ligands – the molecule that binds to the central metal atom of a chemical compound – to yield catalytic activity. Our discovery of functional surface nanoparticles opens the door to using much smaller ratios of these expensive compounds relative to the metal centres.  This drastically reduces the overall cost of the transformations.”

This work at the University of Toronto reminded me of another team also working on green catalysts for chemical reactions and also based in Canada, this time at McGill University. The McGill team lead by Chao-Jun Li was mentioned most recently here in a Jan. 10, 2011 posting where their ‘nanomagnetics’ technology to replace the current toxic catalysts  is described.

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Posted in beauty and cosmetics, nanotechnology, pharmacology | No Comments »

Discover Canadian innovation by staring deeply into your own navel and Mike Laziridis discusses manure (really) at the AAAS Fri., Feb. 17, 2012 afternoon events

Saturday, February 18th, 2012

It was an afternoon event (1:30 – 4:30 pm PST) at the American Association for the Advancement (AAAS) 2012 meeting in Vancouver, “Searching for the Right Space for Innovation.” I realized it was going to be a bunch of academics discussing their research about the Canadian scene; I just didn’t expect it to be so thoroughly self-involved. There was one moment of extreme excitement with everyone madly scribbling or keyboarding. David Wolfe from the University of Toronto mentioned that there is interest is funding risk science research and centres (apparently the Univ. of Toronto is about to open a risk science centre of its own). I’m pretty sure it was the smell of money that occasioned all the activity.

Given that this meeting attracts mainly US scientists and others from outside Canada, I was hoping for a more expansive view of Canadian innovation (the good, the bad, and the ugly). The relentless focus on the minutiae surprised me. I realize that for these academics what I perceive to be minutiae is vitally important. (That’s always true  if you are deeply involved in a topic. I feel much the same way about passive and active voices but the only people who care to discuss this topic at length [I mean 20 or more minutes; occasionally you meet someone who's prepared to argue you {the writer} into the ground but they usually lose interest as the discussion continues] are other writers.)

Given that the AAAS meeting is attracting academics from many different disciplines and from jurisdictions outside Canada, I found this discussion disappointing in its provincialism.

This session was followed by the big event of the day, the plenary lecture by Mike Lazaridis billed as “The Power of Ideas.” One of the founders of Research in Motion (RIM), the company that produced the Blackberry, Lazaridis is well known as a successful technology innovator. He recently stepped down (or was pushed) from his position (with Jim Balsillie) as co-president and co-CEO of RIM after a very bad year (2011) for that company.

In technology circles, there’s a phenomenon where the people who founded the company can grow it to a certain point but no further. Lazaridis and Balsillie grew their company well past the point where most Canadian entrepreneurs have to quit. RIM is quite an extraordinary accomplishment by any standard internationally and I’m not sure why Lazaridis and/or his handlers feel they have to gild it past levels considered tasteful by baroque standards.

Lazaridis is a good speaker and I wish the material had been better. I’m referring specifically to the part where he posed a thought experiment (his term for it) whereby the Blackberry is sent back in time to some giants in the field electronics, Michael Faraday and James Clerk Maxwell.Is there anyone who doesn’t realize that these 19th century geniuses would be hard put to understand the device?As for sending back some textbooks so they could read about the technology, unlike Lazaridis I’m not convinced that would be helpful. Apparently Lazaridis learned technology by reading the technical manuals first. Laziridis has a different starting point than either of these geniuses not least of which was a cultural context that allowed him to grapple with what was then a ‘new’ technology.

Lazaridis did announce that there will be a new centre opening, the Mike and Ophelia Lazaridis Quantum Nano Centre (QNC) at the University of Waterloo (Ontario, Canada). I gather the new opening date is later this year (2012);  it was supposed to open during summer 2011.

There were some charming bits to the talk (high school experiences) and he’s charismatic. As for the manure, this was mentioned in the context of the first urban planning meeting ever held in the 1890′s in New York City. Lazaridis set this up as a joke asking us what we thought the big problem of the 1890′s urban environment could be. I imagine it was meant as a launch point for something more germane to the ‘big ideas’ theme but I knew the punchline (I happened to see an episode of Nova where this information was featured), was tired, and Lazaridis does not appear to have a gift for delivering a comic line so I left. There you have it: day one.

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Posted in science, science communication | 5 Comments »

Ted Sargent and Inerjys

Wednesday, January 11th, 2012

Ted Sargent, Canada Research Chair in Nanotechnology, University of Toronto, has been mentioned here a number of times regarding his work on solar cells. Here are a few of the mostly recent postings (not a complete list), June 28, 2011, July 11, 2011, and Sept. 20, 2011.

Now, a Montréal-based company, Inerjys Ventures has just announced that Ted Sargent has joined their board of advisors. From the Jan. 9, 2012 news item on MarketWatch,

Inerjys Ventures, a $1 billion renewable energy strategic investment fund and global leader in green finance, announced today that it has constituted a board of advisors and named its first members. Inerjys has brought together thought leaders from renewable energy, finance and government to guide its decisions and strategic vision as the world approaches a clean energy economy.

The announcement comes at a decisive time for Inerjys, which was recently featured at the prestigious World Climate Summit in Durban, South Africa. The firm is currently developing several large-scale renewable energy projects worldwide, to be announced as it completes the closing of its renewable energy investment fund, Inerjys Ventures. At a projected capitalization of $1 billion CAD, Inerjys Ventures will be the largest cleantech venture vehicle in Canada and one of the largest in the world. The board will convene regularly to direct the growth of Inerjys and will lend their expertise to analyze investment opportunities in Canada and around the world.

You can learn more about Inerjys here.

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Posted in business, investment, nanotechnology | No Comments »

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