LightSail’s Danielle Fong on the Most Exciting Science

As 2013 was winding down, I asked Danielle Fong what she considered the biggest scientific breakthroughs in the last year.

Fong is the co-founder and chief scientist at LightSail Energy, a Khosla-backed company trying to reinvent the energy grid by storing excess energy in the form of compressed air. (Fascinating profile of Fong, who started college as a teen, and LightSail here.)

Fong’s answer arrived a little late for the obligatory wave of looking-back-at-the-year-that-was stories. But … the response was so compelling we decided to run it in full (edited lightly for clarity, length and to make Paul Graham look sexist — kidding!).

Stick through to the end for hints of some potentially exciting things coming up for LightSail, a company I’m planning to watch closely in 2014.

Photo Credit: Robert Schlatter Danielle Fong, chief scientist at LightSail

My top two picks are, really, themes, and they represent a deepening of our understanding, and an increasing perfection of technology.

It’s hard to pin down exactly one “breakthrough.” The paradigmatic examples are in fact not what they seem.

For example, Alexander Fleming isn’t even the first one to have discovered or written about antibiotic properties of penicillin (as early as the 1870s the mould was written about). He was in a position to look for antibiotics, given his work on antibacterials during the war. And he made the initial discovery in 1928, abandoned clinical work on it in 1931, restarted in 1934, and continued to try to get a chemist to purify it until the 1940s. The development of antibiotics was not just one thing.

For that matter, the lightbulb was a filament, plus a vacuum, plus a high resistance, plus a whole electrical system — generator, mains, feeders, the works. Bulbs existed before Edison, but he brought a system forth to provide lighting.

And the Wright Brothers weren’t the first ones to have achieved flight, but heavier than air (Zeppelins were first) *controlled* flight. They needed to invent new flying paradigms, wing warping, new engines, new propellors, control systems, developed elevators and wings. They tested in wind tunnels, an invention of their own. It wasn’t just one thing — though there certainly was a moment of truth in the air!

Hence, themes. My two picks for the most exciting things in science last year:

1) Exoplanets! – so many worlds teeming with life, all in the sky, perhaps within reach.

So much happened this year. We are in a galaxy with perhaps 100 billion worlds, 17 billion “earth like.” The galaxy may be a fertile garden of life.

What’s driving all of this is an incredible refinement of the transit technique for the detection of exoplanets, culminating in the Kepler spacecraft.

Researchers are really finding their stride in data analysis and techniques, and a plethora of discoveries have resulted.

These discoveries have helped make it possible to imagine humanity spread throughout the stars, and innumerable worlds, and lifeforms abound, waiting to be discovered.

2) How Genes Really Work

Specifically, steadily increasing control and understanding. Take a look at how many of these advances listed here involve epigenetics or gene therapy or the discovery of an important gene or the sequencing of a new species or the use of genetic modification to understand a new organism.

We’re still only scratching the surface here. But genetics isn’t like computer code; it’s chemistry and systems science and ecology. Genes are regulated by the environment, and other genes, and genes regulate the environment in turn. We’re understanding more and more how to introduce genes into new lifeforms, how they’re expressed, regulated, how they mutate, change, how they fold (we caught a ribosome in mid fold!).

We can now even make machines — it is a stretch to call them robots — but machines, nanomachines, out of DNA. (See video below.)

I’m both excited and disappointed with my two picks. They give us amazing new capabilities — dreamt of for a long time, now made real. But they are not the broad new continents of possibility that some hope for in breakthroughs.

Personally, I think that at least one of three things I’ve been working on in 2013 should be on there, eventually. In the future, perhaps, on whatever Wikipedia page you’d read, you’d read that I came up with the idea in 2013. But since none of it is public, and none of it has been proven yet, you’ll only hear about it in a few years, and if LightSail is any indication, it will be another three years before anyone writes about it as a breakthrough, and another three until it is actually real.

ORIGINAL: ReCode

By James Temple

January 6, 2014

NYU-Poly Nano Scientists Reach the Holy Grail in Label-Free Cancer Marker Detection: Single Molecules

ORIGINAL: Polytechnic Institute of New York University
July 24, 2013

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BROOKLYN, N.Y.—Just months after setting a record for detecting the smallest single virus in solution, researchers at the Polytechnic Institute of New York University (NYU-Poly) have announced a new breakthrough: They used a nano-enhanced version of their patented microcavity biosensor to detect a single cancer marker protein, which is one-sixth the size of the smallest virus, and even smaller molecules below the mass of all known markers. This achievement shatters the previous record, setting a new benchmark for the most sensitive limit of detection, and may significantly advance early disease diagnostics. Unlike current technology, which attaches a fluorescent molecule, or label, to the antigen to allow it to be seen, the new process detects the antigen without an interfering label.
Stephen Arnold, university professor of applied physics and member of the Othmer-Jacobs Department of Chemical and Biomolecular Engineering, published details of the achievement in Nano Letters, a publication of the American Chemical Society.

In 2012, Arnold and his team were able to detect in solution the smallest known RNA virus, MS2, with a mass of 6 attograms. Now, with experimental work by postdoctoral fellow Venkata Dantham and former student David Keng, two proteins have been detected: a human cancer marker protein called Thyroglobulin, with a mass of just 1 attogram, and the bovine form of a common plasma protein, serum albumin, with a far smaller mass of 0.11 attogram. “An attogram is a millionth of a millionth of a millionth of a gram,” said Arnold, “and we believe that our new limit of detection may be smaller than 0.01 attogram.”

This latest milestone builds on a technique pioneered by Arnold and collaborators from NYU-Poly and Fordham University. In 2012, the researchers set the first sizing record by treating a novel biosensor with plasmonic gold nano-receptors, enhancing the electric field of the sensor and allowing even the smallest shifts in resonant frequency to be detected. Their plan was to design a medical diagnostic device capable of identifying a single virus particle in a point-of-care setting, without the use of special assay preparations.

At the time, the notion of detecting a single protein—phenomenally smaller than a virus—was set forth as the ultimate goal.

“Proteins run the body,” explained Arnold. “When the immune system encounters virus, it pumps out huge quantities of antibody proteins, and all cancers generate protein markers. A test capable of detecting a single protein would be the most sensitive diagnostic test imaginable.”

To the surprise of the researchers, examination of their nanoreceptor under a transmission electron microscope revealed that its gold shell surface was covered with random bumps roughly the size of a protein. Computer mapping and simulations created by Stephen Holler, once Arnold’s student and now assistant professor of physics at Fordham University, showed that these irregularities generate their own highly reactive local sensitivity field extending out several nanometers, amplifying the capabilities of the sensor far beyond original predictions. “A virus is far too large to be aided in detection by this field,” Arnold said. “Proteins are just a few nanometers across—exactly the right size to register in this space.”

The implications of single protein detection are significant and may lay the foundation for improved medical therapeutics. Among other advances, Arnold and his colleagues posit that the ability to follow a signal in real time—to actually witness the detection of a single disease marker protein and track its movement—may yield new understanding of how proteins attach to antibodies.

Arnold named the novel method of label-free detection “whispering gallery-mode biosensing” because light waves in the system reminded him of the way that voices bounce around the whispering gallery under the dome of St. Paul’s Cathedral in London. A laser sends light through a glass fiber to a detector. When a microsphere is placed against the fiber, certain wavelengths of light detour into the sphere and bounce around inside, creating a dip in the light that the detector receives. When a molecule like a cancer marker clings to a gold nanoshell attached to the microsphere, the microsphere’s resonant frequency shifts by a measureable amount.

The research has been supported by a grant from the National Science Foundation (NSF). This summer, Arnold will begin the next stage of expanding the capacity for these biosensors. The NSF has awarded a new $200,000 grant to him in collaboration with University of Michigan professor Xudong Fan. The grant will support the construction of a multiplexed array of plasmonically enhanced resonators, which should allow a variety of protein to be identified in blood serum within minutes.

The publication in Nano Letters marks the 100th journal-paper published since the 1978 founding of NYU-Poly’s Microparticle Photophysics Laboratory for BioPhotonics, directed by Arnold.

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Bio-Nanowires Conduct Electricity

ORIGINAL: Raijini Rao

▶ Imagine a conducting nanowire, only 3-5 nm wide but many thousand times longer, connecting a microbial community to form mini-power grids. Naturally occurring soil bacteria, such as Geobacter, use these conductivepili for long-range electron transport. How and why do they do this?

▶ All living organisms respire. Our cells break down sugars to obtain energy by extracting electrons that are handed down a relay chain to oxygen, which becomes water. The proteins (cytochromes) that conduct electrons are aided by special metallic centers, studded with iron, so they can cycle between Fe2+ (ferrous) and Fe3+ (ferric) states that differ by one electron. Geobacter uses these cytochromes too, just as our cells do. But oxygen only made its debut a mere 2.4 billion years ago. Before that, ancient bacteria shuttled the electrons to other acceptors, such as sulfides, nitrates and Fe3+. When Geobacter is deprived of oxygen, it grows out long pili into mineral rich rocks and "breathes" iron (drawing on top right). The current is believed to pass between layers of bacteria (middle right image) across a distance of 12 millimetres, which may not seem large, but is 10,000 body lengths to bacteria!

▶ But can proteins conduct current? Researchers knew that the pili were conductive, behaving like ohmic devices (image at bottom right). Although the pili were decorated with cytochromes, they were spaced too far apart to transfer electrons between their metallic centers. When the protein chains were mutated to replace a type of amino acid, the pili lost conductivity. These "aromatic" amino acids have pi-pi orbitals that may be conducting electrons.

▶ Live Wires: Bacterial nanowires can be used in generating microbial energy cells, bioremediation of pollutants (like uranium), and in nano-manufacturing of a variety of devices. The main image shows bacteria growing on metal electrodes.

⚛ Ref:http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3604773/

⚛ Sources: http://www.geobacter.org/Nanowires,http://goo.gl/E6Kpf , http://goo.gl/si6aH ,http://goo.gl/T76L5

Harvard's Wyss Institute and Sony DADC Announce Collaboration on Organs-on-Chips

ORIGINAL: Wyss Institute

Date: Mar 18, 2013

Boston, MA -- Today the Wyss Institute for Biologically Inspired Engineering at Harvard University and Sony DADC announced a collaboration that will harness Sony DADC's global manufacturing expertise to further advance the Institute's Organs-on-Chips technologies. 

Human Organs-on-Chips are composed of a clear, flexible polymer about the size of a computer memory stick, and contain hollow microfluidic channels lined by living human cells -- allowing researchers to recapitulate the physiological and mechanical functions of the organs, and to observe what happens in real time. The goal is to provide more predictive and useful measures of the efficacy and safety of new drugs in humans -- and at a fraction of the time and costs associated with traditional animal testing.

"We are excited to apply Sony DADC's deep manufacturing expertise to confront one of the major challenges in the life sciences by helping to accelerate the translation of the Wyss Institute's Organ-on-Chips from the benchtop to the marketplace," said Christoph Mauracher, Senior Vice President of the BioSciences division of Sony DADC. "The Organs-on-Chips have the potential to revolutionize testing of drugs, chemicals, toxins and cosmetics."

Organs on a Chip from Wyss Institute on Vimeo.

This collaboration builds on the momentum the Wyss Institute team has gained recently on its Organs-on-Chips research program. With support from Defense Advanced Research Projects Agency (DARPA)*, National Institutes of Health (NIH), Food and Drug Administration (FDA), and pharmaceutical partners, more than ten Organs-on-Chips are currently under development at the Wyss Institute, including a lung, heart, liver, kidney, bone marrow, and gut-on-a-chip; there is also a major effort to integrate these organ chips into "human body on-chips" that mimic whole body physiology.

In February, Wyss Founding Director Don Ingber, M.D., Ph.D., who leads the Organs-on-Chips research program, received the prestigious 3Rs Prize from the UK's National Centre for the Replacement, Refinement and Reduction of Animals in Research for the lung-on-a-chip. This month, the Society of Toxicology awarded him the Leading Edge in Basic Science Award for his "seminal scientific contributions and advances to understanding fundamental mechanisms of toxicity."

"Our work with Sony is a wonderful example of the Wyss Institute model in action," said Ingber. "We collaborate with industry to help de-risk the technologies we develop, both technically and commercially, and therefore expedite their translation into real world applications."

###

*Part of this research was sponsored by the U.S. Army Research Office (ARO) and DARPA; the views and conclusions contained in this document are those of the authors and should not be interpreted as representing the official policies, either expressed or implied, of ARO, DARPA or the U.S. Government.

Contacts

Wyss Institute for Biologically Inspired Engineering 

Kristen M. Kusek

+1 617-432-8266

Kristen.kusek@wyss.harvard.edu 

Sony DADC

Manfred Koranda

+43 6246 880 8143

manfred.koranda@sonydadc.com

Breaking the bacteria barrier

ORIGINAL: IBM

The Research Team (from left to right): Dr James L. Hedrick, IBM Research, Dr Yi-Yan Yang, IBN Group Leader, Dr Shaoqiong Liu, IBN Research Scientist, Dr Jeremy Tan, IBN Research Scientist and Li Yan, IBN PhD Candidate.

Bacterial biofilms appearing on the skin and on medical devices and household surfaces are difficult to treat and demonstrate high resistance to antibiotics. Antimicrobial hydrogels developed by IBM Research and the Institute for Bioengineering and Nanotechnology demonstrate 100% efficiency in destruction of these biofilms, with application potential for catheter and medical device coatings, implants, skin and everyday surfaces.

New hydrogel born from semiconductor research may help save lives

We are obsessed with cleanliness. From anti-bacterial cart wipes at the supermarket to individual sized packages of wipes and gels that we can carry in a pocket or a purse - you'd think we were winning in the war against germs.

But in hospitals, clinics and other medical facilities, the potential for infection still exists. Despite advanced sterilization and aseptic techniques, infections associated with medical devices and surfaces have not been eradicated, thanks to the increase in drug-resistant bacteria.

According to the CDC, antibiotic drug resistance in the U.S. costs an estimated $20 billion a year in healthcare costs as well as 8 million additional days spent in the hospital[1]. And hospital-acquired infections are among the top five leading causes of death in the United States and account for up to $11 billion in healthcare spending each year[2].

And while personal anti-bacterial products exist on the market today in the form of the aforementioned hand gels and wipes, these products target very common germs and most contain ethanol as a key ingredient. Ethanol evaporates after a very short time after application and does not provide long-lasting protection.

Cleaning products that effectively destroy bacteria on surfaces, including alcohol and bleach, also break down and/or evaporate after a short period of time and are not transferrable for human application based on their toxicity.

Now imagine a long-lasting substance that is biocompatible and non-toxic, but also biodegradable. A substance that destroys specific types of bacteria but leaves healthy skin and cells alone – one that could be applied to medical facility surfaces, surgical and diagnostic instruments, and even – one day - medical implants.

IBM Research, in association with the Institute of Bioengineering and Nanotechnology in Singapore have taken a first step towards that future with the development of an antimicrobial hydrogel that can break through diseased biofilms and eradicate drug-resistant bacteria upon contact.

“We were driven to develop a more effective therapy against superbugs due to the lethal threat of infection by these rapidly mutating microbes and the lack of novel antimicrobial drugs to fight them. Using the inexpensive and versatile polymer materials that we have developed jointly with IBM, we can now launch a nimble, multi-pronged attack on drug-resistant biofilms which would help to improve medical and health outcomes.”. Dr Yi-Yan Yang, Group Leader, Institute of Bioengineering and Nanotechnology, Singapore

It began with computer chips

The IBM nanomedicine polymer program began in IBM Research labs only four years ago with the mission to improve human health.

The program itself stems from decades of materials development traditionally used for semiconductor technologies. In earlier chip development research, IBM researchers identified specific materials that, when chained together, produced an electrostatic charge that allows microscopic etching on a wafer to be done at a much smaller scale.

This newfound knowledge that characterization of materials could be manipulated at the atomic level to control their movement inspired the team to see what else they could do with these new kinds of polymer structures. They started with methicillin-resistant Staphylococcus aureus (MRSA).

The outcome of that experiment was the creation of what are now playfully known as "ninja polymers" – sticky nanostructures that move quickly to target infected cells in the body, destroy the harmful content inside, and can then disappear by biodegrading without causing damaging side effects or accumulating in the organs. As a bonus, all of this occurs without damaging healthy cells in the area.

The next step was to figure out how to apply this new capability to other applications to help fight harmful bacteria.

On the left is a mature and healthy MRSA biofilm. After the hydrogel is applied, the biofilm is destroyed as seen on the right. Photo Credit: IBN

Zipping molecules and zapping bacteria

Through the precise tailoring of polymers, researchers were able to create macromolecules - molecular structures containing a large number of atoms - which combine water solubility, a positive charge, and biodegradability. When mixed with water and heated to normal body temperature, the polymers self-assemble, swelling into a synthetic gel that is easy to manipulate.

“This is a fundamentally different approach to fighting drug-resistant biofilms. When compared to capabilities of modern-day antibiotics and hydrogels, this new technology carries immense potential. This new technology is appearing at a crucial time as traditional chemical and biological techniques for dealing with drug-resistant bacteria and infectious diseases are increasingly problematic.”. James Hedrick, Advanced Organic Materials Scientist, IBM Research

This capability stems from internal reactions that create a molecular "zipper" effect. Similar to how zipper teeth link together, the short segments on the new polymers interlock, thickening the water-based solution into moldable and highly malleable hydrogels.

When applied to contaminated surfaces, the hydrogel's positive charge attracts negatively charged microbial membranes, like stars and planets being pulled into a black hole. However, unlike other antimicrobials that target the internal machinery of bacteria to try to prevent it from replicating, this hydrogel destroys the bacteria by rupturing the bacteria’s membrane, rendering it completely unable to regenerate or spread.

The hydrogel developed by the team is comprised of more than 90 percent water, making it easy to handle and apply to surfaces. It also makes it potentially viable for eventual inclusion in applications like creams or injectable therapeutics for wound healing, implant and catheter coatings, skin infections or even orifice barriers. It is the first-ever to be biodegradable, biocompatible and non-toxic, potentially making it an ideal tool to combat serious health hazards facing hospital workers, visitors and patients.

By preventing infections before they happen, doctors, hospitals, patients and healthcare providers may one day all benefit from improved medical outcomes and lower healthcare costs. This jointly developed hydrogel may be a key that helps open that door to the future.

Explore this topic

IBM Research produces staph-killing polymers that leave healthy cells alone

Research originally published in the Angewandte Chemie International Edition of the Gesellschaft Deutscher Chemiker

View more hydrogel images and videos

Meet the researchers

Dan Coady

Polymer Chemist, 

IBM Research - Almaden

Amanda Engler

Post Doctoral Researcher, 

IBM Research - Almaden

James Hedrick

Advanced Organic Materials, 

IBM Research - Almaden

1 U.S. Dept. of Health and Human Services, Agency for Healthcare Research and Quality: Hospital-acquired infections dramatically increase trauma patients' risk of in-hospital death and hospital stay

2 Centers for Disease Control and Prevention: Antimicrobial Resistance Posing Growing Health Threat

Researchers Create 'Smart' Molecules

ORIGINAL: 33rd Square

Scientists from the German Nanosystems Initiative have created 'intelligent' molecules that could work in the future as nanoswitches: stimuli such as hot-cold, light-dark or altered salt concentrations can be toggled/switched back and forth between different conformations and thus act by itself as stimulus generator. 

Intelligence may not only a matter of humans and animals. Scientists now speak also of intelligent molecules. The latter directly react to external stimuli and change reversibly their shape. Nanosystems Initiative Munich (NIM) physicists have now demonstrated the process for the first time with a single molecule.

Intelligent molecules could work in the future as nanoswitches: stimuli such as hot-cold, light-dark or altered salt concentrations can be toggled/switched back and forth between different conformations and thus act by itself as stimulus generator. Such molecules can be found in different groups of elements, but especially in proteins and synthetic polymers.

Until the real use of intelligent molecules, scientists still have much to learn about such compounds. The LMU physicists Dr. Michael Nash from the group of Prof. Hermann Gaub, a member of The Cluster of Excellence Nanosystems Initiative Munich (NIM), has now succeeded in making a reaction with a single polymer molecule visible for the first time.

The research was published recently in the journal ACS Nano.

In the experiment, Nash and his colleagues placed a self made synthesized polymer on a gold surface using an atomic force microscope (AFM). One polymer end adhered on the surface and the other end at the tip of the AFM. Once the scientists increased the salt concentration of the surrounding medium, they were able to observe how the molecule collapsed gradually.

"In a highly concentrated salt solution, the polymer compound dehydrates and shrinks," says Dr. Michael Nash, first author of the study. "Back in a weak salt solution, the molecule unfolds again. We have observed both processes in our study for the first time for a single polymer molecule”

The new method of the biophysicists from Munich provides an important element for nanoswitches of the future and their potential use in biosensors, drugs, chromatography procedures and much more. The publication of the journal ACS Nano has been selected as Cover Article, in combination with a 3D graphic of the NIM-media designer (pictured above).

SOURCE NIM

Nanoparticles deliver cargo inside mitochondria

ORIGINAL: Foresight Institute

Shanta Dhar, right, an assistant professor of chemistry in the UGA Franklin College of Arts and Sciences, and doctoral student Sean Marrache have fabricated nanoparticles that boost the effectiveness of drugs by delivering them to the mitochondria of cells (credit: University of Georgia).

Targeted drug delivery is one of the most important contributions of current and near-term nanotechnology to medicine. New research shows that specifically targeting one component of the cell makes nanoparticle-mediated drug delivery much more effective for a variety of applications. A hat tip to KurzweilAI.net for reprinting this University of Georgia news release “UGA researchers boost efficacy of drugs by using nanoparticles to target ‘powerhouse of cells’“:

Nanoparticles have shown great promise in the targeted delivery of drugs to cells, but researchers at the University of Georgia have refined the drug delivery process further by using nanoparticles to deliver drugs to a specific organelle within cells.

By targeting mitochondria, often called “the powerhouse of cells,” the researchers increased the effectiveness of mitochondria-acting therapeutics used to treat cancer, Alzheimer’s disease and obesity in studies conducted with cultured cells.

“The mitochondrion is a complex organelle that is very difficult to reach, but these nanoparticles are engineered so that they do the right job in the right place,” said senior author Shanta Dhar, an assistant professor of chemistry in the UGA Franklin College of Arts and Sciences.

Dhar and her co-author, doctoral student Sean Marrache, used a biodegradable, FDA-approved polymer to fabricate their nanoparticles and then used the particles to encapsulate and test drugs that treat a variety of conditions. Their results were published this week in early edition of the journal Proceedings of the National Academy of Sciences [abstract].

To test the effectiveness of their drug targeting system against cancer, they encapsulated the drug lonidamine, which works by inhibiting energy production in the mitochondria, and, separately, a form of the antioxidant vitamin E. They then treated cultured cancer cells and found that mitochondrial targeting increased the effectiveness of the drugs by more than 100 times when compared to the drugs alone and by five times when compared to the delivery of drugs with nanoparticles that target the outside of cells.

Similarly, the compound curcumin has shown promise in inhibiting formation of the amyloid plaques that are a hallmark of Alzheimer’s disease, but it quickly degrades in the presence of light and is broken down rapidly by the body. By encapsulating curcumin in the mitochondria-targeting nanoparticles, however, the researchers were able to restore the ability of brain cells in culture to survive despite the presence of a compound that encourages plaque formation. Nearly 100 percent of the cells treated with the mitochondria-targeting nanoparticles survived in the presence of the plaque-inducing compound, compared to 67 percent of cells treated with free curcumin and 70 percent of cells treated with nanoparticles that target the outside of cells.

Finally, the researchers encapsulated the obesity drug 2,4-DNP—which works by making energy production in the mitochondria less efficient—in their nanoparticles and found that it reduced the production of fat by cultured cells known as preadipocytes by 67 percent compared to cells treated with the drug alone and by 61 percent of cells treated with nanoparticles that target the outside of cells.

“A lot of diseases are associated with dysfunctional mitochondria, but many of the drugs that act on the mitochondria can’t get there,” Marrache said. “Rather than try to alter the drugs, which can reduce their effectiveness, we encapsulate them in these nanoparticles and precisely deliver them to the mitochondria.”

Dhar said that getting drugs to the mitochondria is no simple feat. Upon entering cells, nanoparticles enter a sorting center known as the endosome. The first thing Dhar and Marrache had to demonstrate was that the nanoparticles escape from the endosome and don’t end up in the cells’ disposal center, the lysosome.

The mitochondria itself is protected by two membranes separated by an interstitial space. The outer membrane only permits molecules of a certain size to pass through, while the inner membrane only permits molecules of a given range of charges to pass. The researchers constructed a library of nanoparticles and tested them until they identified the optimum size range—64 to 80 nanometers, or approximately 1,000 times finer than the width of a human hair—and an optimum surface charge, plus 34 millivolts.

Dhar notes the components they used to create the nanoparticles are FDA approved and that their methods are highly reproducible and therefore have the potential to be translated into clinical settings. The researchers are currently testing their targeted delivery system in rodents and say that preliminary results are promising.

“Mitochondrial dysfunctions cause many disorders in humans,” Dhar said, ” so there are several potential applications for this delivery system.”

Subject to the usual caveat that these nanoparticles are still in an early stage of testing, having been tested only in cell culture, it is remarkable that such effective targeting to reach the matrix of the mitochondria was achieved by the relatively crude strategy of optimizing only particle size and surface charge through engineering polymer composition. So success was achieved through clever application of biological knowledge more than through sophisticated atomically precise construction. It will be fascinating to watch the evolution of this technology as ever more sophisticated construction leads to increasing effectiveness. While we are waiting, this targeting of drug delivery to mitochondria is likely to be especially helpful because so many pathologies seem rooted in imperfections and consequences of the symbiosis that led to eukaryotic cells, and all complex life on Earth, nearly two billion years ago.

—James Lewis, PhD