Tag Archives: nanomedicine

Hypersensitivity to nanomedicine: the CARPA reaction

There is some intriguing research (although I do have a reservation) into some unexpected side effects that nanomedicine may have according to a Feb. 23, 2016 news item on phys.org,

Keywords such as nano-, personalized-, or targeted medicine sound like bright future. What most people do not know, is that nanomedicines can cause severe undesired effects for actually being too big! Those modern medicines easily achieve the size of viruses which the body potentially recognizes as foreign starting to defend itself against —a sometimes severe immune response unfolds.

The CARPA-phenomenon (Complement Activation-Related PseudoAllergy) is a frequent hypersensitivity response to nanomedicine application. Up to 100 patients worldwide suffer from severe reactions, such as cardiac distress, difficulty of breathing, chest and back pain or fainting each day when their blood gets exposed to certain nanoparticles during medical treatment. Every 10 days one patient even dies due to an uncontrollable anaphylactoid reaction.

Apart from being activated in a different way, this pseudoallergy has the same symptoms as a common allergy, bearing a crucial difference:  the reaction is taking place without previous sensitizing exposure to a substance, making it hard to predict, whether a person will react to a specific nanodrug or be safe. Intrigued by this vital challenge, János Szebeni from Semmelweis University, Budapest, has been working with scientific verve on the decipherment and prevention of the CARPA phenomenon for more than 20 years. With his invaluable support De Gruyter´s European Journal of Nanomedicine (EJNM) lately dedicated an elaborate compilation of the most recent scientific advances on CARPA, presented by renowned experts on the subject.

A Feb. 23, 2016 De Gruyter Publishers press release, which originated the news item, provides more detail,

Interestingly it´s pigs that turned out to serve as best model for research on the complex pathomechanism, diagnosis and potential treatment of CARPA. “Pigs´ sensitivity equals that of humans responding most vehemently to reactogenic nanomedicines”, Szebeni states.  In a contribution to EJNM´s compilation on CARPA, Rudolf Urbanics and colleagues show that reactions to specific nanodrugs are even quantitatively reproducible in pigs … . Szebeni: “This is absolutely rare in allergy-research. In these animals the endpoint of the overreaction is reflected in a rise of pulmonary arterial pressure, being as accurate as a Swiss watch”. Pigs can thus be used for drug screening and prediction of the CARPAgenic potential of nanomedicines. This becomes increasingly important with the ever growing interest in modern drugs requiring reliable preclinical safety assays during the translation process from bench to bedside. Results might also help to personalize nanomedicine administration schedules during for example the targeted treatment of cancer. The same holds true for a very recently developed in vitro immunoassay. By simply using a patient´s blood sample, it tests for potential CARPA reactions even before application of specific nanodrugs.

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

Lessons learned from the porcine CARPA model: constant and variable responses to different nanomedicines and administration protocols by Rudolf Urbanics, Péter Bedőcs, János Szebeni. European Journal of Nanomedicine. Volume 7, Issue 3, Pages 219–231, ISSN (Online) 1662-596X, ISSN (Print) 1662-5986, DOI: 10.1515/ejnm-2015-0011, June 2015

This paper appears to be open access.

As for reservations, I’m not sure what occasioned the news release so many months post publication of the paperand it should be noted that János Szebeni seems to be the paper’s lead author and the editor of the European Journal of Nanomedicine.

Alberta’s diagnostic tool on a chip (aka point-of-care diagnostics)

2012 seems to be continuing a trend that 2011 enjoyed, the race to develop diagnostics-on-a-chip (aka handheld diagnostics or point-of-care diagnostics). The latest story is from Tannara Yelland for Canadian University Press in a Jan. 3, 2012 article titled, Where nanotechnology and medicine meet; University of Alberta researcher shrinks medical tests, makes them more affordable,

Researchers have made great strides in diagnostic tools for detecting the genetic abnormalities that lead to or signal cancers, but many of these remain solely the province of experimental labs because of practical impediments like the cost of equipment.

Aiming specifically to make clinical medicine easier and less expensive to conduct, Pilarski [Linda Pilarski, a University of Alberta oncology professor and Canada Research Chair in Biomedical Nanotechnology] and her team have created a microfluidic chip about the size of a thumbnail that can test for up to 80 different genetic markers of cancer.

“Most of the things we were doing were much too complicated to do in a clinical lab,” Pilarski said. “Their technology has to be far more regulated than what we’re doing in the lab. It may be feasible [to use current experimental tests] in a big research hospital, but not in Stony Plains [Alberta], in our little health care centre, for example.

“And with tests that are feasible, they’re feasible only because they study many samples at once.”

… They have reversed the normal procedure, studying several samples for one disease, in the hopes of making tests easier to do in more remote locations.

There are about 80 small posts attached to a glass chip, and each post carries out a different test for a different mutation. Unlike the currently used larger equipment, Pilarski says these chips should allow clinicians to perform the tests within an hour, and rather than make patients wait a nerve-wracking few days for their results, they can find out before they leave the lab.

While Pilarski’s work has focused on cancer, the chip she has developed could be used to test for any number of illnesses, which is precisely what medical equipment company Aquila Diagnostics plans to do with Pilarski’s technology.

“Some of the first things to come out might not be for cancer but for infectious diseases,” Pilarski said.

My most recent posting on handheld diagnostic tools, Dec. 22, 2011, noted the Grand Challenges grants (from the Bill & Melinda Gates Foundation and from the Canadian not-for-profit agency called Grand Challenges) awarded to researchers working on the problem of diagnosing infectious diseases in the developing world. From the posting,

The grants announced today are part of the Point-of-Care Diagnostics (POC Dx) Initiative [of the Bill & Melinda Gates Foundation], a research and development program with the goal of creating new diagnostic platforms that enable high-quality, low-cost diagnosis of disease, and also facilitate sustainable markets for diagnostic products, a key challenge in the developing world. This first phase of the POC Dx Initiative is focused on developing new technologies and identifying implementation issues to address the key barriers for clinical diagnostics in the developing world.

Getting back to  Pilarski and the Alberta initiative, the company mentioned in the article, Aquila Diagnostics is based in Edmonton, Alberta and is associated with the University of Alberta. From the company website home page,

Aquila is a medical device company focused on point-of-care diagnosis testing for blood borne infectious diseases and cancer. The Company is developing a portable diagnostic system that delivers rapid, low-cost, multiparameter tests without the need for highly-skilled operators. Aquila’s gel post PCR technology is protected and under licence from the University of Alberta.

I look forward to hearing more about these initiatives as they get closer to market.

Grand Challenges, point-of-care diagnostics, and a note on proliferating bureaucracies

Last week, the Bill & Melinda Gates Foundation announced a $21.1 M grant over three years for research into point-of-care diagnostic tools for developing nations. A Canadian nongovermental organization (NGO) will be supplementing this amount with $10.8 M for a total of $31.9 M. (source: Dec. 16, 2011 AFP news item [Agence France-Presse] on MedicalXpress.com)

At this point, things get a little confusing. The Bill & Melinda Gates Foundation has a specific program called Grand Challenges in Global Health and this grant is part of that program. Plus, the Canadian NGO is called Grand Challenges Canada (couldn’t they have found a more distinctive name?), which is funded by a federal Canadian government initiative known as the Development Innovation Fund (DIF). Here’s a little more from the Who We Are page,

In the 2008 Federal Budget the Government of Canada announced the creation of the Development Innovation Fund (DIF) to “support the best minds in the world as they search for breakthroughs in global health and other areas that have the potential to bring about enduring changes in the lives of the millions of people in poor countries.” The Government of Canada is committing $225 million over five years to the Development Innovation Fund.

The Development Innovation Fund will be delivered by Grand Challenges Canada working with the International Development Research Centre (IDRC) and the Canadian Institutes of Health Research (CIHR). As the Government of Canada’s lead on the Development Innovation Fund, the International Development Research Centre will draw on decades of experience managing research projects and ensure that developing country researchers and concerns are front and centre in this exciting new initiative. The initial activities of the Development Innovation Fund will be in global health.

Grand Challenges Canada is a unique and independent not-for-profit organization dedicated to improving the health and well-being of people in developing countries by integrating scientific, technological, business and social innovation both in Canada and in the developing world. Grand Challenges Canada works with the International Development Research Centre, Canadian Institutes of Health Research, and other global health foundations and organizations committed to discovering sustainable solutions to the world’s most pressing health challenges. Grand Challenges Canada is hosted by the McLaughlin-Rotman Centre for Global Health, University Health Network and University of Toronto.

So if I understand this rightly, the Canadian federal government created a new fund and then created a new NGO to administer that fund. I wonder how much money is required administratively for this NGO which exists solely to distribute DIF. I’m glad to see that someone is getting some money for research out of this but it does seem labyrinthine at best.

On a happier, more productive now, here’s the type of research this money will be used for (from the MedicalXpress.com news item),

“Imagine a hand-held, battery-powered device that can take a drop of blood and, within minutes, tell a healthcare worker in a remote village whether a feverish child has malaria, dengue or a bacterial infection,” said Peter Singer, head of Grand Challenges Canada which is partnering with the Microsoft founder Bill Gates’s charitable organization on the project.

In this last year I have posted a few times about similar projects for handheld diagnostic devices, in my Aug. 4, 2011 posting ‘Diagnostics on a credit card‘ and in my Feb. 15, 2011 posting ‘Argento, nano, and PROOF‘. There’s a lot of interest in these devices whether they’re intended for use in developing countries or not.

I have tracked down the Dec. 15, 2011 news release from the Bill & Melinda Gates Foundation to get more details about this specific project,

The grants announced today are part of the Point-of-Care Diagnostics (POC Dx) Initiative, a research and development program with the goal of creating new diagnostic platforms that enable high-quality, low-cost diagnosis of disease, and also facilitate sustainable markets for diagnostic products, a key challenge in the developing world. This first phase of the POC Dx Initiative is focused on developing new technologies and identifying implementation issues to address the key barriers for clinical diagnostics in the developing world.

They also give some examples of projects that will be receiving funding from this grant,

Examples of projects receiving funding:

  • Seventh Sense Biosystems, a company located in Cambridge MA, is developing TAP—a painless, low-cost blood collection device which aims to allow easy, push-button sampling of blood. This simple collection process would reduce training requirements and enable diagnostics closer to the point of need.
  • David Beebe and researchers at the University of Wisconsin are developing a sample purification system that seeks to better filter and concentrate biomarkers from patient samples. This system will be designed for use in impoverished settings.
  • Axel Scherer of the California Institute of Technology, along with collaborators at Dartmouth College, will develop a prototype quantitative PCR (qPCR) amplification/detection component module—a low cost, easy-to-use technology that can rapidly detect a wide range of diseases.

There’s additional detail about grantees in the Grand Challenges Canada Dec. 16, 2011 news release,

One grantee, Bigtec Labs in Bangalore, India, has already developed a handheld analyser called a mini-PCR (Polymerase Chain Reaction) machine capable of identifying malaria from a DNA fingerprint.

―A colleague here one day was ill with what he thought was food poisoning,” said

B. Chandrasekhar Nair, Director of Bigtec Labs. “We ran a blood sample through our mini-PCR and it turned out to be malaria.‖ Immediately treated, the colleague returned to health within a week.

With its CAD $1.3 million grant, Bigtec will use nano-materials to develop a sophisticated filter to concentrate pathogen DNA from samples of blood, sputum, urine, or nasal and throat swabs. Once concentrated, the DNA can be processed and illnesses identified in the mini-PCR.

The innovative projects receiving funding include:

 Dr. Dhananjaya Dendukuri from Achira Labs in Bangalore India, and Dr. Nandini Dendukuri from McGill University in Montreal are developing a piece of silk that can be used as a cost-effective and simple diagnostic for blood and urine samples. Called Fabchips (Fabric Chips) the woven diagnostic has the added benefit of providing jobs to local artisans and being environmentally friendly.

 Dr. David Goldfarb, a Canadian working in Botswana, is testing a simple, rapid, easy-to-use swab for the detection of diarrheal disease in the developing world.

 Dr. Wendy Stevens from the University of Witwatersrand in South Africa is testing new point-of-care technologies for the integrated management of HIV and TB treatment to encourage equity, affordability and accessibility to treatment.

 Dr. Patricia Garcia at the Universidad Peruana Cayetano Heredia in Peru will look at ways to overcome social and commercial barriers to delivering point-of-care diagnostic tests aimed at improving maternal and child health – two of the UN‘s Millennium Development goals for 2015.

There’s a full list of all the grantees (Grand Challenges Canada and the Bill & Melinda Gates Foundation) and links to videos here.

Here’s a sample video of Dr. Dhananjaya Dendukuri to get you started,

Congratulations to the researchers!

Micro needle patches project gets Grand Challenges Explorations grant

The project being funded with a Grand Challenges Explorations grant (from the Bill & Melinda Gates Foundation) reminds me a lot of the nanopatch that Mark Kendall and his team have been developing in Australia (a project last mentioned in my Aug. 3, 2011 posting). This new initiative comes from the Georgia Institute of Technology and is aimed at the eradication of polio. From the Nov. 7, 2011 news item on Nanowerk,

The Georgia Institute of Technology will receive funding through Grand Challenges Explorations, an initiative created by the Bill & Melinda Gates Foundation that enables researchers worldwide to test unorthodox ideas that address persistent health and development challenges. Mark Prausnitz, Regents’ professor in Georgia Tech’s School of Chemical and Biomolecular Engineering, will pursue an innovative global health research project focused on using microneedle patches for the low-cost administration of polio vaccine through the skin in collaboration with researchers Steve Oberste and Mark Pallansch of the US Centers for Disease Control and Prevention (CDC).

The goal of the Georgia Tech/CDC project is to demonstrate the scientific and economic feasibility for using microneedle patches in vaccination programs aimed at eradicating the polio virus. Current vaccination programs use an oral polio vaccine that contains a modified live virus. This vaccine is inexpensive and can be administered in door-to-door immunization campaigns, but in rare cases the vaccine can cause polio. There is an alternative injected vaccine that uses killed virus, which carries no risk of polio transmission, but is considerably more expensive than the oral vaccine, requires refrigeration for storage and must be administered by trained personnel. To eradicate polio from the world, health officials will have to discontinue use of the oral vaccine with its live virus, replacing it with the more expensive and logistically-complicated injected vaccine.

Prausnitz and his CDC collaborators believe the use of microneedle patches could reduce the cost and simplify administration of the injected vaccine.

Iwonder if this team working at the microscale rather than the nanoscale, as Kendall’s team does, is finding some of the same benefits, from my August 3, 2011 posting,

Early stage testing in animals so far has shown a Nanopatch-delivered flu vaccine is effective with only 1/150th of the dose compared to a syringe and the adjuvants currently required to boost the immunogenicity of vaccines may not be needed. [emphases mine]

I find the notion that only 1/150th of a standard syringe dosage can be effective quite extraordinary. I wonder if this will hold true in human clinical trials.

If they get similar efficiencies at the microscale as they do at the nanoscale, the expense associated with vaccines using killed viruses should plummet dramatically. I do have one thought, do we have to eradicate the polio virus in a ‘search and destroy mission’? Couldn’t we learn to live with them peacefully while discouraging their noxious effects on our own biology?

Aussies, Yanks, Canucks, and Koreans collaborate on artificial muscles

I received a media release (from the University of British Columbia [UBC]) about artificial muscles. I was expecting to see Dr. Hongbin Li’s name as one of the researchers but this is an entirely different kind of artificial muscle. Dr. Li works with artificial proteins to create new biomaterials (my May 5, 2010 posting). This latest work published in Science Express, Oct. 13, 2011,  involves carbon nanotubes and teams from Australia, Canada, Korea, and the US. From the Oct. 13, 2011, UBC media release,

An international team of researchers has invented new artificial muscles strong enough to rotate objects a thousand times their own weight, but with the same flexibility of an elephant’s trunk or octopus limbs.

In a paper published online today on Science Express, the scientists and engineers from the University of British Columbia, the University of Wollongong in Australia, the University of Texas at Dallas and Hanyang University in Korea detail their innovation. The study elaborates on a discovery made by research fellow Javad Foroughi at the University of Wollongong.

Using yarns of carbon nanotubes that are enormously strong, tough and highly flexible, the researchers developed artificial muscles that can rotate 250 degrees per millimetre of muscle length. This is more than a thousand times that of available artificial muscles composed of shape memory alloys, conducting organic polymers or ferroelectrics, a class of materials that can hold both positive and negative electric charges, even in the absence of voltage.

Here’s how the UBC media release recounts the story of these artificial muscles (Aside: The Australians take a different approach; I haven’t seen any material from the University of Texas at Dallas or the University of Hanyang),

The new material was devised at the University of Texas at Dallas and then tested as an artificial muscle in Madden’s [Associate Professor, John Madden, Dept. of Electrical and Computer Engineering] lab at UBC. A chance discovery by collaborators from Wollongong showed the enormous twist developed by the device. Guided by theory at UBC and further experiments in Wollongong and Texas, the team was able to extract considerable torsion and power from the yarns.

The Australians, not unnaturally focus on their own contributions, and, somewhat unexpectedly discuss nanorobots. From the ARC (Australian Research Council) Centre of Excellence for Electromaterials Science (ACES) at the University of Wollongong news release (?) [ETA Oct. 17, 2011: I forgot to include a link to the Australian news item; and here’s a link to the Oct. 16, 2011 Australian news item on Nanowerk] ,

The possibility of a doctor using tiny robots in your body to diagnose and treat medical conditions is one step closer to becoming reality today, with the development of artificial muscles small and strong enough to push the tiny Nanobots along.

Although Nanorobots (Nanobots) have received much attention for the potential medical use in the body, such as cancer fighting, drug delivery and parasite removal, one major hurdle in their development has been the issue of how to propel them along in the bloodstream.

An international collaborative team led by researchers at UOW’s Intelligent Polymer Research Institute, part of the ARC Centre of Excellence for Electromaterials Science (ACES), have developed a new twisting artificial muscle that could be used for propelling nanobots.   The muscles use very tough and highly flexible yarns of carbon nanotubes (nanoscale cylinders of carbon), which are twist-spun into the required form.  When voltage is applied, the yarns rotate up to 600 revolutions per minute, then rotate in reverse when the voltage is changed.

Due to their complexity, conventional motors are very difficult to miniaturise, making them unsuitable for use in nanorobotics.  The twisting artificial muscles, on the other hand, are simple and inexpensive to construct either in very long, or in millimetre lengths.

Interesting, non?

There’s an animation illustrating the nanorobots and the muscles,

In the animated video below, you first see a few bacteria like creatures swimming about. Their rotating flagella are highlighted with some detail of the flagella motor turning the “hook” and “filament” parts of the tail. We next see a similar type of rotating tail produced by a length of carbon nanotube thread that is inside a futuristic microbot. The yarn is immersed in a liquid electrolyte along with another electrode wire. Batteries and an electrical circuit are also inside the bot. When a voltage is applied the yarn partially untwists and turns the filament. Slow discharging of the yarn causes it to re-twist. In this way, we can imagine the micro-bot is propelled along in a series of short spurts.

I think the graphics resemble conception complete with sperm and eggs but I can see the nanorobots too. Here’s your chance to take a look,

ETA Oct. 14, 2011 11:20 am PST: I found a copy of the University of Texas at Dallas news release posted on Oct. 13, 2011 at Nanowerk. No mention of nanobots but if you’re looking for additional technical explanations, this would be good to read.

Making nanotechnology-enabled body parts

In my Aug. 2, 2011 posting, Body parts nano style, I mentioned a scaffolding, developed by Dr. Alex Seifalian, made of a biocomposite. Today’s (Aug. 16, 2011) news item on Nanowerk offers more information about the biocomposite,

The composite made from POSS® and PCU (Polyhedral Oligomeric Silsesquioxane & Poly (carbonateurea) Urethane) had been developed by Dr. Alex Seifalian of the University College London Medical School. The effort has been so effective that Dr. Seifalian says he now has six more tracheas on order. … Moreover the composite scaffold can be transformed into a human artery, vein, heart valve, tear duct or trachea. It might in the future be used to make larynxes, noses, breasts, ears or other parts of the human body.

Hybrid has developed a platform technology called POSS® (Polyhedral Oligomeric Silsesquioxane). It is a revolutionary new Nanotechnology based on silicon-derived building blocks that provide nanometerscale control to dramatically improve the properties of traditional polymers. They release no VOCs and, thereby, produce no odor or air pollution. They are biocompatible and recyclable. POSS® nanoscopic chemical technology provides unique opportunities to create revolutionary material combinations through a melding of the desirable properties of ceramics and polymers at the 1 nm length scale. These new combinations enable the circumvention of classic material performance trade-offs by exploiting the synergy and properties that only occur between materials at the nanoscale.

Yes, it’s a bit puffy with hype but that’s to be expected when the news item is released by the company, Hybrid Plastics, that produces at least part of the biocomposite (POSS®) used to create the scaffolding.

Using copyright laws to censor a science blogger?

Techdirt’s Mike Masnick highlighted an incident where an astronomy blog was taken down with a DMCA (US Digital Millenium Copyright Act) notice earlier this week over an astronomy dispute. From Masnick’s July 22, 2011 article,

James Litwin points us to a report about how someone — and, tragically, the party is never actually named — filed a DMCA takedown notice to Blogger to try to take down Ian Musgrave’s Astroblogger site.

According to Nancy Atkinson on the Universe Today blog’s July 20, 2011 posting, the Astroblog site was unavailable for a few days,

Astronomer and blogger Ian Musgrave from South Australia has been active in debunking the misinformation and nonsense that is being disseminated about Comet Elenin. He has written several wonderful posts featuring the actual realities of this long-period lump of dirty ice that has, for some reason, attracted the attention of doomsdayers, 2012ers, and end-of-the-world scaremongers. Earlier this week, Ian’s Elenin posts on his Astroblog were taken down by the web host, as someone filed a claim for alleged violation of the Digital Millennium Copyright Act (DMCA). “Given that there is no copyrighted material on these pages, with either material generated entirely by me or links to and citation of publicly available material, I believe this was just a frivolous attack on people countering Elenin nonsense” Ian said.

Atkinson goes on to provide all of the information Musgrave generated over a number of days on Astroblog in a single posting. I think it’s a convenient to catch up with this issue for someone like me who until Masnick’s article had never heard about Elenin or the concerns it has generated.

Thankfully, Astroblog has been reinstated and Musgrave continues to post about Elenin and other matters. His July 22, 2011 post features a story about how an individual, citizen scientist (amateur astronomer) bought time on a remote telescope (in the Canary Islands) to test an hypothesis about Elenin,

There has been a lot of angst about the size of comet C/2010 X1 Elenin on the internet, with some people worried it is either a Brown Dwarf Star or the Satellite of a Brown Dwarf. Both Leonid Elenin and I have used maths and simulations to show that the comet must be small, but people continue to be anxious, and are discussing the matter endlessly on various discussion groups.

Except a commenter called Astronut, who did something unthinkable, rather than endlessly nattering he actually tested the hypothesis that Elenin was big.

He bought time on a remote telescope (one of the Slooh scopes) in the Canary Islands, and measured the position of asteroid (74732) 1999 RQ176 twenty -four hours after it’s close encounter with comet Elenein on May 20.

I won’t give any more details, please read the story to find out what happens next but, if you don’t have time to do that, you can rest easy.

I’m sorry to see a copyright law as a form of censorship.

Vampire batteries in Germany too?

I posted a very brief item (April 3, 2009) about some research being done at the University of British Columbia (UBC in Vancouver, Canada) on potential medical devices called ‘vampire batteries’, which use blood as fuel. The UBC team is not alone in its pursuit. A July 15, 2011 news item, Electricity from blood sugar, on Nanowerk, highlights similar research in Germany,

Implants that obtain their energy from blood sugar and oxygen: Dr. Sven Kerzenmacher at the Department of Microsystems Engineering (IMTEK) of the University of Freiburg is researching the development of biological fuel cells with the goal of finding an inexhaustible source of power in the human body. He has been awarded the 2011 FAM Research Prize for his dissertation by the Forum for Applied Microsystems Technology (FAM). …

Researchers have yet to find an optimal method for supplying implantable medical microsystems with electrical energy. The batteries of a pacemaker, for instance, need to be replaced after roughly eight years—meaning a strenuous and expensive surgical intervention for the patient. An alternative approach is to use rechargeable batteries. However, the necessity of recharging the batteries greatly reduces the patient’s quality of life. The idea behind Sven Kerzenmacher’s research, on the other hand, is the possibility of using implantable glucose fuel cells on the basis of noble metal catalysts like platinum. Such catalysts are particularly well suited for use in implant systems due to their long-term stability and the fact that they can be sterilized. In the future, systems equipped with these fuel cells could be supplied with power by way of a continuous electrochemical reaction between glucose and oxygen from the tissue fluid.

Here’s what the team at UBC was doing (from the April 1, 2009 New Scientist article by Kurt Kleiner,),

A team at the University of British Columbia in Vancouver, Canada, has created tiny microbial fuel cells by encapsulating yeast cells in a flexible capsule. They went on to show the fuel cells can generate power from a drop of human blood plasma.

There is no mention of clinical trials, human or otherwise in the news item about the work in Germany or at UBC, which makes it difficult to guess how close they are to using these fuel cells in patients but I imagine there are still several years of lab work ahead given this comment from Kleiner’s 2009 article about the UBC team’s work. A colleague at Cornell noted,

The work is a step in the right direction, but huge challenges remain, says Lars Angenent, who works on microbial fuel cells at Cornell University.

For instance, to keep the yeast cells healthy, their waste products will need to be removed without allowing any harmful substances to leach out into the blood stream.

Happy Canada Day to everyone! and news about implantable devices for the prevention diabetes-related vision loss

Although it’s going to be years (I imagine several) before patients at risk for diabetes-related blindness will be able to benefit from this work, it’s certainly exciting news from the University of British Columbia (UBC). One of their research teams has tested a device that could be implanted behind an eye to release medications when an external sensor is activated. ETA July 4, 2011: I took another look at that news release and I’m now not sure that I correctly understood the term “… on-demand release of drugs” which I meant an external locus of control.

Here’s more from the June 29, 2011 UBC  news release,

A team of engineers and scientists at the University of British Columbia has developed a device that can be implanted behind the eye for controlled and on-demand release of drugs to treat retinal damage caused by diabetes.

Diabetic retinopathy is the leading cause of vision loss among patients with diabetes. The disease is caused by the unwanted growth of capillary cells in the retina, which in its advanced stages can result in blindness.

The novel drug delivery mechanism is detailed in the current issue of Lab on a Chip, a multidisciplinary journal on innovative microfluidic and nanofluidic technologies.

The lead authors are recent PhD mechanical engineering graduate Fatemeh Nazly Pirmoradi, who completed the study for her doctoral thesis, and Mechanical Engineering Assoc. Prof. Mu Chiao, who studies nanoscience and microelectromechanical systems for biological applications.

The co-authors are Prof. Helen Burt and research scientist John Jackson at the Faculty of Pharmaceutical Sciences.

“We wanted to come up with a safe and effective way to help diabetic patients safeguard their sight,” says Chiao who has a family member dealing with diabetic retinopathy.

A current treatment for diabetic retinopathy is laser therapy, which has side effects, among them laser burns or the loss of peripheral or night vision. Anti-cancer drugs may also used to treat the disease. However, these compounds clear quickly from the bloodstream so high dosages are required, thus exposing other tissues to toxicity.

Key to UBC’s innovation is the ability to trigger the drug delivery system through an external magnetic field. The team accomplished this by sealing the reservoir of the implantable device – which is no larger than the head of a pin – with an elastic magnetic polydimethylsiloxane (silicone) membrane. A magnetic field causes the membrane to deform and discharge a specific amount of the drug, much like squeezing water out of a flexible bottle.

In a series of lab tests, the UBC researchers loaded the implantable device with the drug docetaxel and triggered the drug release at a dosage suitable for treating diabetic retinopathy. They found that the implantable device kept its integrity with negligible leakage over 35 days.

They also monitored the drug’s biological effectiveness over a given period, testing it against two types of cultured cancer cells, including those found in the prostate. They found that they were able to achieve reliable release rates.

“The docetaxel retained its pharmacological efficacy for more than two months in the device and was able to kill off the cancer cells,” says Pirmoradi.

The UBC device offers improvements upon existing implantable devices for drug delivery, says Chiao.

“Technologies available now are either battery operated and are too large for treating the eye, or they rely on diffusion, which means drug release rates cannot be stopped once the device is implanted – a problem when patients’ conditions change.”

Pirmoradi says it will be several years before the UBC device is ready for patient use. “There’s a lot of work ahead of us in terms of biocompatibility and performance optimization.”

The team is also working to pinpoint all the possible medical applications for their device so that they can tailor the mechanical design to particular diseases

There’s no information as to whether this is work being done at microscale or nanoscale or both for that matter. I do note that the device is described as being “no larger than the head of a pin” so it’s possible to physically see and/or handle it. I wonder what the response would be if the device were invisible to the human eye. I expect that response would be dependent on how unpleasant the effects from the previous technology/ies used have proved to be.

Alberta researchers at the National Institute of Nanotechnology create nano coating for stainless steel implants in bid to trick body’s immune system

A research team in Alberta has found a way to coat stainless steel with glass silica and carbohydrates so the metal (already in general use) can be more effective in implanted biomedical devices. From the April 27, 2011 news item on Nanowerk,

Implanted biomedical devices, such as cardiac stents, are implanted in over 2 million people every year, with the majority made from stainless steel. Stainless steel has many benefits – strength, generally stability, and the ability to maintain the required shape long after it has been implanted. But, it can also cause severe problems, including blood clotting if implanted in an artery, or an allergenic response due to release of metal ions such as nickel ions.

This particular initiative, devising a means to trick the body’s immune system into better acceptance of implants, is part of a larger project where the goal is,

… to allow cross-blood type organ transplants, meaning that blood types would not necessarily need to be matched between donor and recipient when an organ becomes available for transplantation.

In the meantime, the team has found a means that they hope will make the stainless steel implants easier for the immune system to accept,

… sophisticated carbohydrate (sugar) molecules needed to be attached to the stainless steel surface to bring about the necessary interaction with the body’s immune system. Its inherent stainless characteristic makes stainless steel a difficult material to augment with new functions, particularly with the controlled and close-to-perfect coverage needed for biomedical implants. The Edmonton-based team found that by first coating the surface of the stainless steel with a very thin layer (60 atoms deep) of glass silica using a technique available at the National Institute for Nanotechnology, called Atomic Layer Deposition (ALD), they could overcome the inherent non-reactivity of the stainless steel. The silica provide a well-defined “chemical handle” through which the carbohydrate molecules, prepared in the Alberta Ingenuity Centre for Carbohydrate Science, could be attached. Once the stainless steel had been controlled, the researchers demonstrated that the carbohydrate molecules covered the stainless steel in a highly controlled way, and in the correct orientation to interact with the immune system.

In trying to find out a little more about this project, I found a presentation* from 2008 (or earlier) made by Todd Lowary, Jillian Buriak, and Lori West, presumably for investment purposes, about another initiative associated with this project titled, Infant Heart Transplants and Nanotechnology. Here’s the hypothesis from slide 3 of the presentation,

Hypothesis: Exposing a newborn to ABO antigens attached to a nanoparticle or stent will induce tolerance during immune development and in turn allow transplants across the blood-group barrier.

Since a baby’s immune system isn’t fully developed at birth, exposing a child in need of a cardiac transplant to a suitably nanoparticle-coated stent would theoretically allow the child to develop tolerance for blood group types other than its own thereby allowing a cross-blood type organ transplant. Towards the end of the presentation (which isn’t dated), they have a timeline which includes filing for various patents and a proposed date of 2013 for human clinical trials.

*The presentation is on the Alberta Centre for Advanced Microsystems and Nanotechnology Products (ACAMP). According to their About page,

ACAMP (Alberta Centre for Advanced MNT Products) is a not for profit organization that provides specialized services to micro nano technology clients.

ACAMP’s services encompass key areas identified as critical for the commercialization of MNT products – Marketing & Business Development, Product Development, Packaging and Assembly, Test and Characterization.

That’s it for today.

ETA July 4, 2011: There’s a May 16, 2011 news item by Cameron Chai on Azonano about this team which offers additional information.