Tag Archives: nanobots

Maybe nano drug delivery not so magical after all?

There’s a lot of talk about the potential for a better way to treat disease with more accurate delivery of nanoparticle-based medicines to specific areas that need the treatment. For example, current treatments which shrink and eliminate cancer tumours also destroy healthy tissue and often have deleterious side effects while a nanoparticle-based treatment could seek out and eliminate the tumour only with few or no side effects. However, new research suggests that tumours may be more complex than previously understood.

From a Jan. 14, 2015 news item on Azonano,

Nanoparticle drugs–tiny containers packed with medicine and with the potential to be shipped straight to tumors–were thought to be a possible silver bullet against cancer. However new cancer drugs based on nanoparticles have not improved overall survival rates for cancer patients very much. Scientists at the University of North Carolina at Chapel Hill now think that failure may have less to do with the drugs and tumors than it does the tumor’s immediate surroundings.

The work, published in Clinical Cancer Research, merges relatively old and new ideas in cancer treatment, on one hand underscoring the importance of personalized medicine and on the other, reinforcing a relatively new idea that the tumor microenvironment might affect the delivery of drugs to tumors – a factor that may alter drug delivery from person to person, from cancer to cancer and even from tumor to tumor.

A Jan. 13, 2015 University of North Carolina news release (also on EurekAlert), which originated the news item, provides more details about the research,

“Tumors create bad neighborhoods,” said William Zamboni, the study’s senior author and an associate professor at the UNC Eshelman School of Pharmacy. “They spawn leaky, jumbled blood vessels that are like broken streets, blind alleys and busted sewers. There are vacant lots densely overgrown with collagen fibers. Immune-system cells patrolling the streets might be good guys turned bad, actually working for the tumor. And we’re trying to get a large truckload of medicine through all of that.”

In their work, Zamboni and colleagues from the UNC Lineberger Comprehensive Cancer Center and the UNC School of Medicine joined forces to see how much of the standard small-molecule cancer drug doxorubicin and its nanoparticle version, Doxil, actually made it into two varieties of triple-negative breast-cancer tumor models created by UNC’s Chuck Perou, the May Goldman Shaw Distinguished Professor of Molecular Oncology at the UNC School of Medicine and a professor at UNC Lineberger. Triple-negative breast cancer accounts for 10 to 17 percent of cases and has a poorer prognosis than other types of breast cancer.

At first, what they saw was no surprise: significantly more of the nanodrug Doxil made it into both triple-negative breast-cancer tumors compared with the standard small-molecule doxorubicin. “That’s nothing new,” Zamboni said. “We’ve seen that for twenty years.” They also saw the same amount of doxorubin in both tumors.

What did surprise them was that significantly more of the nanodrug Doxil – twice as much – was delivered to the C3-TAg triple-negative breast cancer tumor than to the T11 triple-negative breast cancer tumor.

“These tumors are subtypes of a subtype of one kind of cancer and are relatively closely related,” said Zamboni. “If the differences in delivering nanoagents to these two tumors are so significant, we can only imagine what the differences might be between breast cancer and lung cancer.”

Zamboni and his team suggest that better profiling of tumors and their microenvironments would allow doctors not only to better identify patients who would most benefit from nanoparticle-based cancer therapy, but also that clinicians may need to learn more about a patient’s tumor before prescribing treatment with one of the newer nanoparticle drugs.

This work gives the Israeli project I wrote about in my Jan. 7, 2015 post regarding a human clinical trial of nanobot delivery of a drug treatment (the world’s first) a new perspective. As a medical writer friend of mine (Susan Baxter) notes, these things are always more complicated than we think they’ll be and she adds tumours change over time.

Given how often we’ve discovered the human body is a complex, interwoven set of ecosystems, it’s perplexing that so much of the discussion around treatment is still  reductionist, i.e., drug kill tumour.

Getting back to this current research, here’s a link to and a citation for the paper,

Effects of Tumor Microenvironment Heterogeneity on Nanoparticle Disposition and Efficacy in Breast Cancer Tumor Models by Gina Song, David B. Darr, Charlene M. Santos, Mark Ross, Alain Valdivia, Jamie L. Jordan, Bentley R. Midkiff, Stephanie Cohen, Nana Nikolaishvili-Feinberg, C. Ryan Miller, Teresa K. Tarrant, Arlin B. Rogers, Andrew C. Dudley, Charles M. Perou, and William C. Zamboni. CCR-14-0493 Clin Cancer Res December 1, 2014 20 6083 doi: 10.1158/1078-0432 Published Online First September 17, 2014

This paper is behind a paywall of sorts. I haven’t seen this particular designation before but in addition to purchasing a subscription or short term access, there’s an option called: “patientACCESS – Patients/Caregivers desiring access to articles.” I’m not sure if that’s fee-based or not.

Surgical nanobots to be tested in humans in 2015?

Thanks to James Lewis at the Foresight’s Institute blog and his Jan. 6, 2015 posting about an an announcement of human clinical trials for surgical nanobots (Note: Links have been removed),

… as structural DNA nanotechnology rapidly expanded the repertoire of atomically precise nanostructures that can be fabricated, it became possible to fabricate functional DNA nanostructures incorporating logic gates to deliver and release molecular cargo for medical applications, as we reported a couple years ago (DNA nanotechnology-based nanorobot delivers cell suicide message to cancer cells). More recently, DNA nanorobots have been coated with lipid to survive immune attack inside the body.

Lewis then notes this (Note: A link has been removed),

 … “Ido Bachelet announces 2015 human trial of DNA nanobots to fight cancer and soon to repair spinal cords“:

At the British Friends of Bar-Ilan University’s event in Otto Uomo October 2014 Professor Ido Bachelet announced the beginning of the human treatment with nanomedicine. He indicates DNA nanobots can currently identify cells in humans with 12 different types of cancer tumors.

A human patient with late stage leukemia will be given DNA nanobot treatment. Without the DNA nanobot treatment the patient would be expected to die in the summer of 2015. Based upon animal trials they expect to remove the cancer within one month.

The information was excerpted from Brian Wang’s Dec. 27, 2014 post on his Nextbigfuture blog,

One Trillion 50 nanometer nanobots in a syringe will be injected into people to perform cellular surgery.

The DNA nanobots have been tuned to not cause an immune response. They have been adjusted for different kinds of medical procedures. Procedures can be quick or ones that last many days.

Using DNA origami and molecular programming, they are reality. These nanobots can seek and kill cancer cells, mimic social insect behaviors, carry out logical operators like a computer in a living animal, and they can be controlled from an Xbox. Ido Bachelet from the bio-design lab at Bar Ilan University explains this technology and how it will change medicine in the near future.

I advise reading both Wang’s and Lewis’ posts in their entirety. To give you a sense of how their posts differ (Lewis is more technical), I solicited information from the websites hosting their blog postings.

Here’s more about Wang from the About page on the Nextbigfuture blog,

Brian L. Wang, M.B.A. is a long time futurist. A lecturer at the Singularity University and Nextbigfuture.com author. He worked on the most recent ten year plan for the Institute for the Future and at a two day Institute for the Future workshop with Universities and City planners in Hong Kong (advising the city of Hong Kong on their future plans). He had a TEDx lecture on Energy. Brian is available as a speaker for corporations and organizations that value accurate and detailed insight into the development of technology global trends.

Lewis provides a contrast (from the About page listing Lewis on the Foresight Institute website),

Jim received a B.A. in chemistry from the University of Pennsylvania in 1967, an M.A. in chemistry from Harvard University in 1968, and a Ph.D. in chemistry, from Harvard University in 1972. After doing postdoctoral research at the Swiss Institute for Experimental Cancer Research, Lausanne, Switzerland, from 1971-1973, Jim did research in the molecular biology of tumor viruses at Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, from 1973-1980, first as a postdoctoral researcher, and then as a Staff Investigator and Senior Staff Investigator. He continued his research as an Associate Member, Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA, from 1980-1988, and then joined the Bristol-Myers Squibb Pharmaceutical Research Institute in Seattle, WA, as a Senior Research Investigator from 1988-1996. Since 1996 he has been working as a consultant on nanotechnology.

Getting back to Bachelet, his team’s work, a precursor for this latest initiative, has been featured here before in an April 11, 2014 post,

This latest cockroach item, which concerns new therapeutic approaches, comes from an April 8, 2014 article by Sarah Spickernell for New Scientist (Note: A link has been removed),

It’s a computer – inside a cockroach. Nano-sized entities made of DNA that are able to perform the same kind of logic operations as a silicon-based computer have been introduced into a living animal.

Ido Bachelet can be seen in this February 2014 video describing the proposed surgical nanobots,

Bar-Ilan University where Bachelet works is located in Israel. You can find more information about this work and more on the Research group for Bio-Design website.

Molecular robots (nanobots/nanorobots): a promising start at Oxford University

‘Baby steps’ is how they are describing the motion and the breakthrough in functional molecular robots at the University of Oxford. From a Dec. 11, 2014 news item on phys.org,

A walking molecule, so small that it cannot be observed directly with a microscope, has been recorded taking its first nanometre-sized steps.

It’s the first time that anyone has shown in real time that such a tiny object – termed a ‘small molecule walker’ – has taken a series of steps. The breakthrough, made by Oxford University chemists, is a significant milestone on the long road towards developing ‘nanorobots’.

‘In the future we can imagine tiny machines that could fetch and carry cargo the size of individual molecules, which can be used as building blocks of more complicated molecular machines; imagine tiny tweezers operating inside cells,’ said Dr Gokce Su Pulcu of Oxford University’s Department of Chemistry. ‘The ultimate goal is to use molecular walkers to form nanotransport networks,’ she says.

A Dec. 10, 2014 University of Oxford science blog post by Pete Wilton, which originated the news item, describes one of the problem with nanorobots,

However, before nanorobots can run they first have to walk. As Su explains, proving this is no easy task.

For years now researchers have shown that moving machines and walkers can be built out of DNA. But, relatively speaking, DNA is much larger than small molecule walkers and DNA machines only work in water.

The big problem is that microscopes can only detect moving objects down to the level of 10–20 nanometres. This means that small molecule walkers, whose strides are 1 nanometre long, can only be detected after taking around 10 or 15 steps. It would therefore be impossible to tell with a microscope whether a walker had ‘jumped’ or ‘floated’ to a new location rather than taken all the intermediate steps.

The post then describes how the researchers solved the problem,

… Su and her colleagues at Oxford’s Bayley Group took a new approach to detecting a walker’s every step in real time. Their solution? To build a walker from an arsenic-containing molecule and detect its motion on a track built inside a nanopore.

Nanopores are already the foundation of pioneering DNA sequencing technology developed by the Bayley Group and spinout company Oxford Nanopore Technologies. Here, tiny protein pores detect molecules passing through them. Each base disrupts an electric current passed through the nanopore by a different amount so that the DNA base ‘letters’ (A, C, G or T) can be read.

In this new research, they used a nanopore containing a track formed of five ‘footholds’ to detect how a walker was moving across it.

‘We can’t ‘see’ the walker moving, but by mapping changes in the ionic current flowing through the pore as the molecule moves from foothold to foothold we are able to chart how it is stepping from one to the other and back again,’ Su explains.

To ensure that the walker doesn’t float away, they designed it to have ‘feet’ that stick to the track by making and breaking chemical bonds. Su says: ‘It’s a bit like stepping on a carpet with glue under your shoes: with each step the walker’s foot sticks and then unsticks so that it can move to the next foothold.’ This approach could make it possible to design a machine that can walk on a variety of surfaces.

There is a video illustrating the molecular walker’s motion, (courtesy University of Oxford),

There is as noted in Wilton’s post, more work to do,

It’s quite an achievement for such a tiny machine but, as Su is the first to admit, there are many more challenges to be overcome before programmable nanorobots are a reality.

‘At the moment we don’t have much control over which direction the walker moves in; it moves pretty randomly,’ Su tells me. ‘The protein track is a bit like a mountain slope; there’s a direction that’s easier to walk in so walkers will tend to go this way. We hope to be able to harness this preference to build tracks that direct a walker where we want it to go.’

The next challenge after that will be for a walker to make itself useful by, for instance, carrying a cargo: there’s already space for it to carry a molecule on its ‘head’ that it could then take to a desired location to accomplish a task.

Su comments: ‘We should be able to engineer a surface where we can control the movement of these walkers and observe them under a microscope through the way they interact with a very thin fluorescent layer. This would make it possible to design chips with different stations with walkers ferrying cargo between these stations; so the beginnings of a nanotransport system.’

These are the first tentative baby steps of a new technology, but they promise that there could be much bigger strides to come.

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

Continuous observation of the stochastic motion of an individual small-molecule walker by Gökçe Su Pulcu, Ellina Mikhailova, Lai-Sheung Choi, & Hagan Bayley. Nature Nanotechnology (2014) doi:10.1038/nnano.2014.264 Published online 08 December 2014

This paper is behind a paywall.

Medical nanobots (nanorobots) and biocomputing; an important step in Russia

Russian researchers have reported a technique which can make logical calculations from within cells according to an Aug. 19, 2014 news item on ScienceDaily,

Researchers from the Institute of General Physics of the Russian Academy of Sciences, the Institute of Bioorganic Chemistry of the Russian Academy of Sciences and MIPT [Moscow Institute of Physics and Technology] have made an important step towards creating medical nanorobots. They discovered a way of enabling nano- and microparticles to produce logical calculations using a variety of biochemical reactions.

An Aug. 19 (?), 2014 MIPT press release, which originated the news item, provides a good beginner’s explanation of bioengineering in the context of this research,

For example, modern bioengineering techniques allow for making a cell illuminate with different colors or even programming it to die, linking the initiation  of apoptosis [cell death] to the result of binary operations.

Many scientists believe logical operations inside cells or in artificial biomolecular systems to be a way of controlling biological processes and creating full-fledged micro-and nano-robots, which can, for example, deliver drugs on schedule to those tissues where they are needed.

Calculations using biomolecules inside cells, a.k.a. biocomputing, are a very promising and rapidly developing branch of science, according to the leading author of the study, Maxim Nikitin, a 2010 graduate of MIPT’s Department of Biological and Medical Physics. Biocomputing uses natural cellular mechanisms. It is far more difficult, however, to do calculations outside cells, where there are no natural structures that could help carry out calculations. The new study focuses specifically on extracellular biocomputing.

The study paves the way for a number of biomedical technologies and differs significantly from previous works in biocomputing, which focus on both the outside and inside of cells. Scientists from across the globe have been researching binary operations in DNA, RNA and proteins for over a decade now, but Maxim Nikitin and his colleagues were the first to propose and experimentally confirm a method to transform almost any type of nanoparticle or microparticle into autonomous biocomputing structures that are capable of implementing a functionally complete set of Boolean logic gates (YES, NOT, AND and OR) and binding to a target (such as a cell) as result of a computation. This method allows for selective binding to target cells, as well as it represents a new platform to analyze blood and other biological materials.

The prefix “nano” in this case is not a fad or a mere formality. A decrease in particle size sometimes leads to drastic changes in the physical and chemical properties of a substance. The smaller the size, the greater the reactivity; very small semiconductor particles, for example, may produce fluorescent light. The new research project used nanoparticles (i.e. particles of 100 nm) and microparticles (3000 nm or 3 micrometers).

Nanoparticles were coated with a special layer, which “disintegrated” in different ways when exposed to different combinations of signals. A signal here is the interaction of nanoparticles with a particular substance. For example, to implement the logical operation “AND” a spherical nanoparticle was coated with a layer of molecules, which held a layer of spheres of a smaller diameter around it. The molecules holding the outer shell were of two types, each type reacting only to a particular signal; when in contact with two different substances small spheres separated from the surface of a nanoparticle of a larger diameter. Removing the outer layer exposed the active parts of the inner particle, and it was then able to interact with its target. Thus, the team obtained one signal in response to two signals.

For bonding nanoparticles, the researchers selected antibodies. This also distinguishes their project from a number of previous studies in biocomputing, which used DNA or RNA for logical operations. These natural proteins of the immune system have a small active region, which responds only to certain molecules; the body uses the high selectivity of antibodies to recognize and neutralize bacteria and other pathogens.

Making sure that the combination of different types of nanoparticles and antibodies makes it possible to implement various kinds of logical operations, the researchers showed that cancer cells can be specifically targeted as well. The team obtained not simply nanoparticles that can bind to certain types of cells, but particles that look for target cells when both of two different conditions are met, or when two different molecules are present or absent. This additional control may come in handy for more accurate destruction of cancer cells with minimal impact on healthy tissues and organs.

Maxim Nikitin said that although this is just as mall step towards creating efficient nanobiorobots, this area of science is very interesting and opens up great vistas for further research, if one draws an analogy between the first works in the creation of nanobiocomputers and the creation of the first diodes and transistors, which resulted in the rapid development of electronic computers.

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

Biocomputing based on particle disassembly by Maxim P. Nikitin, Victoria O. Shipunova, Sergey M. Deyev, & Petr I. Nikitin. Nature Nanotechnology (2014) doi:10.1038/nnano.2014.156 Published online 17 August 2014

This paper is behind a paywall.

University of Alberta (Canada) student nanorobotics team demonstrates potential medical technology in competitiion

A University of Alberta (Canada) nanorobotics team has entered its nanobot system into the International Mobile Micro/nanorobotics Competition in Karlsruhe, Germany, as part of the ICRA Robot Challenges at the IEEE (Institute of Electrical and Electronics Engineers) International Conference on Robotics and Automation (ICRA) being held May 6 – 10, 2013 in Karlsruhe, Germany. From the May 6, 2013 news item on Nanowerk,

A team of engineering students is putting a twist on robotics, developing a nano-scale robotics system that could lead to new medical therapies.

In less than a year, the U of A team has assembled a working system that manipulates nano-scale ‘robots’. The team uses magnets to manipulate a droplet filled with iron oxide nanoparticles. Barely visible to the naked eye, the droplet measures 400-500 micrometres.

The May 3, 2013 University of Alberta news release by Richard Cairney, which originated the news item, describes the system,

Using a joystick, team members control the robot, making it travel along a specific route, navigate an obstacle course or to push micro-sized objects from one point to another.

The challenge is simple in concept but highly technical and challenging to execute: the team first injects a water droplet with iron oxide nanoparticles into into oil. The droplet holds its shape because it is encased in a surfactant—a soap-like formula that repels water on one side and attracts water on the other.

“It’s like a capsule,” said team member Yang Gao, who is working on her master’s degree in chemical engineering. “It’s a vehicle for the nanoparticles.”

The iron-filled droplet is placed in a playing ‘field’ measuring 2 x 3 millimetres. The team uses four magnets mounted each side of the rectangular field to move the droplet in a figure-8, manoeuvring it through four gates built into the field.

“We use the magnets to pull the droplet,” explains electrical engineering PhD student Remko van den Hurk.

In a second challenge, the team will be required to use the droplet as a bulldozer of sorts, to arrange micro-scale objects that measure 200 x 300 micrometres into a particular order on an even smaller playing field.

The competition has its serious side, these nanobots could one day be used in medical applications.

In the meantime there’s the competition, good luck!

Swarming robot droplets

The robot droplets are a bit bigger than you might expect, the size of ping pong balls, but the idea is intriguing and for those who’ve read Michael Crichton’s book, Prey, it could seem quite disturbing (from the University of Colorado Boulder multimedia page for ‘tiny robots’),

For anyone unfamiliar with Crichton’s Prey, here’s an excerpt from the Wikipedia entry about the book which features nanobots operating as a swarm,

… As a result, hazardous elements such as the assemblers, the bacteria, and the nanobots were blown into the desert, evolving and eventually forming autonomous swarms. These swarms appear to be solar-powered and self-sufficient, reproducing and evolving rapidly. The swarms exhibit predatory behavior, attacking and killing animals in the wild, using code that Jack himself worked on. Most alarmingly, the swarms seem to possess rudimentary intelligence, the ability to quickly learn and to innovate. The swarms tend to wander around the fab plant during the day but quickly leave when strong winds blow or night falls.

The Dec. 14, 2012 posting by Alan on the Science Business website describes,

A computer science lab at University of Colorado in Boulder is building a miniature, limited-function robot designed to work in a swarm of similar devices. Computer science professor Nikolaus Correll and colleagues are building these small devices that they call droplets as building blocks for increasingly complex systems.

A University of Colorado Boulder Dec. 14, 2012 news release provides more details,

Correll and his computer science research team, including research associate Dustin Reishus and professional research assistant Nick Farrow, have developed a basic robotic building block, which he hopes to reproduce in large quantities to develop increasingly complex systems.

Recently the team created a swarm of 20 robots, each the size of a pingpong ball, which they call “droplets.” When the droplets swarm together, Correll said, they form a “liquid that thinks.”

To accelerate the pace of innovation, he has created a lab where students can explore and develop new applications of robotics with basic, inexpensive tools.

Similar to the fictional “nanomorphs” depicted in the “Terminator” films, large swarms of intelligent robotic devices could be used for a range of tasks. Swarms of robots could be unleashed to contain an oil spill or to self-assemble into a piece of hardware after being launched separately into space, Correll said.

Correll plans to use the droplets to demonstrate self-assembly and swarm-intelligent behaviors such as pattern recognition, sensor-based motion and adaptive shape change. These behaviors could then be transferred to large swarms for water- or air-based tasks.

Correll hopes to create a design methodology for aggregating the droplets into more complex behaviors such as assembling parts of a large space telescope or an aircraft.

There’s also talk about creating gardens in space,

He [Correll] also is continuing work on robotic garden technology he developed at the Massachusetts Institute of Technology in 2009. Correll has been working with Joseph Tanner in CU-Boulder’s aerospace engineering sciences department to further develop the technology, involving autonomous sensors and robots that can tend gardens, in conjunction with a model of a long-term space habitat being built by students.

Correll says there is virtually no limit to what might be created through distributed intelligence systems.

“Every living organism is made from a swarm of collaborating cells,” he said. “Perhaps some day, our swarms will colonize space where they will assemble habitats and lush gardens for future space explorers.”

The scientists don’t seem to harbour any trepidations, I guess they’re leaving that to the writers.

RNA (ribonucleic acid) video game

I am a great fan of  Foldit, a protein-folding game I have mentioned several times here (my first posting about Foldit was Aug. 6, 2010) and now via the Foresight Insitute’s July 16, 2012 blog posting, I have discovered an RNA video game (Note: I have removed links),

As we pointed out a few months ago, the greater complexity of folding rules for RNA compared to its chemical cousin DNA gives RNA a greater variety of compact, three-dimensional shapes and a different set of potential functions than is the case with DNA, and this gives RNA nanotechnology a different set of advantages compared to DNA nanotechnology … Proteins have even more complex folding rules and an even greater variety of structures and functions. We also noted here that online gamers playing Foldit topped scientists in redesigning a protein to achieve a novel enzymatic activity that might be especially useful in developing molecular building blocks for molecular manufacturing. Now KurzweilAI.net brings news of an online game that allows players to design RNA molecules …

Here’s more from the KurzwelAI.net June 26, 3012 posting about the new RNA game EteRNA,

EteRNA, an online game with more than 38,000 registered users, allows players to design molecules of ribonucleic acid — RNA — that have the power to build proteins or regulate genes.

EteRNA players manipulate nucleotides, the fundamental building blocks of RNA, to coax molecules into shapes specified by the game.

Those shapes represent how RNA appears in nature while it goes about its work as one of life’s most essential ingredients.

EteRNA was developed by scientists at Stanford and Carnegie Mellon universities, who use the designs created by players to decipher how real RNA works. The game is a direct descendant of Foldit — another science crowdsourcing tool disguised as entertainment — which gets players to help figure out the folding structures of proteins.

Here’s how the EteRNA folks describe this game (from the About EteRNA page),

By playing EteRNA, you will participate in creating the first large-scale library of synthetic RNA designs. Your efforts will help reveal new principles for designing RNA-based switches and nanomachines — new systems for seeking and eventually controlling living cells and disease-causing viruses. By interacting with thousands of players and learning from real experimental feedback, you will be pioneering a completely new way to do science. Join the global laboratory!

The About EteRNA webpage also offers a discussion about RNA,

RNA is often called the “Dark Matter of Biology.” While originally thought to be an unstable cousin of DNA, recent discoveries have shown that RNA can do amazing things. They play key roles in the fundamental processes of life and disease, from protein synthesis and HIV replication, to cellular control. However, the full biological and medical implications of these discoveries is still being worked out.

RNA is made of four nucleotides (A, C,G,and U, which stand for adenine, cytosine, guanine, and uracil). Chemically, each of these building blocks is made of atoms of carbon, oxygen, nitrogen, phosphorus, and hydrogen. When you design RNAs with EteRNA, you’re really creating a chain of these nucleotides.

RNA Nucleotides (from the About EteRNA webpage)

Scientists do not yet understand all of RNA’s roles, but we already know about a large collection of RNAs that are critical for life: (see the Thermus Thermophilus image representing following points)

  1. mRNAs are short copies of a cell’s DNA genome that gets cut up, pasted, spliced, and otherwise remixed before getting translated into proteins.
  1. rRNA forms the core machinery of an ancient machine, the ribosome. This machine synthesizes the proteins of your cells and all living cells, and is the target of most antibiotics.
  2. miRNAs (microRNAs) are short molecules (about 22-letters) that are used by all complex cells as commands for silencing genes and appear to have roles in cancer, heart disease, and other medical problems.
  3. Riboswitches are ubiquitous in bacteria. They sense all sorts of small molecules that could be food or signals from other bacteria, and turn on or off genes by changing their shapes. These are interesting targets for new antibiotics.
  4. Ribozymes are RNAs that can act as enzymes. They catalyze chemical reactions like protein synthesis and RNA splicing, and provide evidence of RNA’s dominance in a primordial stage of Life’s evolution.
  5. Retroviruses, like Hepatitis C, poliovirus, and HIV, are very large RNAs coated with proteins.
  6. And much much more… shRNA, piRNA, snRNA, and other new classes of important RNAs are being discovered every year.

Thermus Thermophilus – Large Subunit Ribosomal RNA
Source: Center for Molecular Biology (downloaded from the About EteRNA webpage)

I do wonder about the wordplay EteRNA/eternal. Are these scientists trying to tell us something?

Magical nanobots at University of Florida kill (almost) 100% of Hepatitis C virus—in the lab

I’ve always preferred the term nanobots but the folks at the University of Florida are calling them nanorobots, from the July 16, 2012 news item on phys.org,

University of Florida researchers have moved a step closer to treating diseases on a cellular level by creating a tiny particle that can be programmed to shut down the genetic production line that cranks out disease-related proteins.

In laboratory tests, these newly created “nanorobots” all but eradicated hepatitis C virus infection. The programmable nature of the particle makes it potentially useful against diseases such as cancer and other viral infections.

The research effort, led by Y. Charles Cao, a UF associate professor of chemistry, and Dr. Chen Liu, a professor of pathology and endowed chair in gastrointestinal and liver research in the UF College of Medicine, is described online this week in the Proceedings of the National Academy of Sciences.

The news item originated with a July 16, 2012 news release from the University of Florida which goes on to explain how the researchers succeeded,

The Holy Grail of nanotherapy is an agent so exquisitely selective that it enters only diseased cells, targets only the specified disease process within those cells and leaves healthy cells unharmed.

To demonstrate how this can work, Cao and colleagues, with funding from the National Institutes of Health, the Office of Naval Research and the UF [University of Florida] Research Opportunity Seed Fund, created and tested a particle that targets hepatitis C virus in the liver and prevents the virus from making copies of itself.

Hepatitis C infection causes liver inflammation, which can eventually lead to scarring and cirrhosis. The disease is transmitted via contact with infected blood, most commonly through injection drug use, needlestick injuries in medical settings, and birth to an infected mother. More than 3 million people in the United States are infected and about 17,000 new cases are diagnosed each year, according to the Centers for Disease Control and Prevention. Patients can go many years without symptoms, which can include nausea, fatigue and abdominal discomfort.

Current hepatitis C treatments involve the use of drugs that attack the replication machinery of the virus. But the therapies are only partially effective, on average helping less than 50 percent of patients, according to studies published in The New England Journal of Medicine and other journals. Side effects vary widely from one medication to another, and can include flu-like symptoms, anemia and anxiety.

Cao and colleagues, including graduate student Soon Hye Yang and postdoctoral associates Zhongliang Wang, Hongyan Liu and Tie Wang, wanted to improve on the concept of interfering with the viral genetic material in a way that boosted therapy effectiveness and reduced side effects.

The particle they created can be tailored to match the genetic material of the desired target of attack, and to sneak into cells unnoticed by the body’s innate defense mechanisms.

Recognition of genetic material from potentially harmful sources is the basis of important treatments for a number of diseases, including cancer, that are linked to the production of detrimental proteins. It also has potential for use in detecting and destroying viruses used as bioweapons.

The new virus-destroyer, called a nanozyme, has a backbone of tiny gold particles and a surface with two main biological components. The first biological portion is a type of protein called an enzyme that can destroy the genetic recipe-carrier, called mRNA, for making the disease-related protein in question. The other component is a large molecule called a DNA oligonucleotide that recognizes the genetic material of the target to be destroyed and instructs its neighbor, the enzyme, to carry out the deed. By itself, the enzyme does not selectively attack hepatitis C, but the combo does the trick.

“They completely change their properties,” Cao said.

In laboratory tests, the treatment led to almost a 100 percent decrease in hepatitis C virus levels. In addition, it did not trigger the body’s defense mechanism, and that reduced the chance of side effects. Still, additional testing is needed to determine the safety of the approach. [emphases mine]

This treatment builds on some previous research,

The UF nanoparticle design takes inspiration from the Nobel prize-winning discovery of a process in the body in which one part of a two-component complex destroys the genetic instructions for manufacturing protein, and the other part serves to hold off the body’s immune system attacks. This complex controls many naturally occurring processes in the body, so drugs that imitate it have the potential to hijack the production of proteins needed for normal function. The UF-developed therapy tricks the body into accepting it as part of the normal processes, but does not interfere with those processes.

Since there’s no mention of human clinical trials, I’m guessing that we are at least 10 years from seeing this therapeutic agent on the market.

After drafting this post yesterday (July 17, 2012) and while waiting to post it today, I found Dexter Johnson’s July 17 2012 posting where he makes some important points about this research (Note: I have removed a link),

Of course, this is a long way from becoming a treatment anytime soon. A major caveat is that the use of nanotreatments for the targeting and destroying of abnormal cells like cancer cells is always problematic since those cells are “still us” as George Whitesides noted some time back.  It’s always a bit of a tricky business to make sure that nanoparticles are targeting those biological processes within us that we want stopped and not the ones we want to keep.

Dexter goes on to comment about using the terms ‘nanobots’ or ‘nano robots'; he’s less sanguine about it than I am.

Driving stick with your nanobots

According to a May 24, 2012 news item on Nanowerk, Chinese scientists have developed a ‘clutch’ to control speed in nanomotors. There’s an excellent explanation of the research in a May 29, 2012 posting by Guest_Jim_* on the Overclockers Club website,

Automatic transmission is fairly useful for many people who just need a car that gets them from point A to point B. They may not have as much control during the trip as someone with a manual transmission, but they do not need it. In the nanoscale world though, control is needed, which is why Chinese researchers have created a nanoclutch, as reported by the American Institute of Physics.

Unlike the transmission in your car, this device does not use any gears.

Here’s how it works (from the May 24,2012 news item on Nanowerk),

The nanoclutch consists of two carbon nanotubes (CNTs), one inside the other, separated by a film of water. Electrowetting forces control the friction between the water and the inner and outer walls of the CNTs. When the two tubes are electrically charged, the water confined between them can transmit the torque from the inner tube to the outer tube, and the device is said to be in the engaged state. When the CNTs are uncharged, the device is in the disengaged state.

… Though further work is needed, they say the model may be helpful in designing and manufacturing nanorobots.

You can find the abstract for the paper here  (although the paper itself is behind a paywall). From the abstract,

Importantly, the proposed CNT-CC-SRNC [charge-controlled speed-regulating nanoclutch] can perform stepless speed-regulating function through changing the magnitude of the charge assigned on CNT atoms.

If I read this rightly, it means that they can exert a very high level of control which could prove handy with nanobots. Here’s the full citation for the paper,

J. Appl. Phys. 111, 114304 (2012); http://dx.doi.org/10.1063/1.4724344 (5 pages)

Carbon nanotube-based charge-controlled speed-regulating nanoclutch

Zhong-Qiang Zhang, Hong-Fei Ye, Zhen Liu, Jian-Ning Ding, Guang-Gui Cheng, Zhi-Yong Ling, Yong-Gang Zheng, Lei Wang, and Jin-Bao Wang

For anyone who may not be familiar with the slang, ‘driving stick’ means driving with a manual transmission.