Tag Archives: Angela Belcher

100 percent efficiency transporting the energy of sunlight from receptors to reaction centers

Genetic engineering has been combined with elements of quantum physics to find a better way of transferring the energy derived from sunlight from the receptors to the reaction centers (i.e., photosynthesis). From an Oct. 15, 2015 news item on Nanowerk,

Nature has had billions of years to perfect photosynthesis, which directly or indirectly supports virtually all life on Earth. In that time, the process has achieved almost 100 percent efficiency in transporting the energy of sunlight from receptors to reaction centers where it can be harnessed — a performance vastly better than even the best solar cells.

One way plants achieve this efficiency is by making use of the exotic effects of quantum mechanics — effects sometimes known as “quantum weirdness.” These effects, which include the ability of a particle to exist in more than one place at a time [superposition], have now been used by engineers at MIT to achieve a significant efficiency boost in a light-harvesting system.

Surprisingly, the MIT [Massachusetts Institute of Technology] researchers achieved this new approach to solar energy not with high-tech materials or microchips — but by using genetically engineered viruses.

An Oct. 15, 2015 MIT news release (also on EurekAlert), which originated the news item, recounts an exciting tale of interdisciplinary work and an international collaboration,

This achievement in coupling quantum research and genetic manipulation, described this week in the journal Nature Materials, was the work of MIT professors Angela Belcher, an expert on engineering viruses to carry out energy-related tasks, and Seth Lloyd, an expert on quantum theory and its potential applications; research associate Heechul Park; and 14 collaborators at MIT and in Italy.

Lloyd, a professor of mechanical engineering, explains that in photosynthesis, a photon hits a receptor called a chromophore, which in turn produces an exciton — a quantum particle of energy. This exciton jumps from one chromophore to another until it reaches a reaction center, where that energy is harnessed to build the molecules that support life.

But the hopping pathway is random and inefficient unless it takes advantage of quantum effects that allow it, in effect, to take multiple pathways at once and select the best ones, behaving more like a wave than a particle.

This efficient movement of excitons has one key requirement: The chromophores have to be arranged just right, with exactly the right amount of space between them. This, Lloyd explains, is known as the “Quantum Goldilocks Effect.”

That’s where the virus comes in. By engineering a virus that Belcher has worked with for years, the team was able to get it to bond with multiple synthetic chromophores — or, in this case, organic dyes. The researchers were then able to produce many varieties of the virus, with slightly different spacings between those synthetic chromophores, and select the ones that performed best.

In the end, they were able to more than double excitons’ speed, increasing the distance they traveled before dissipating — a significant improvement in the efficiency of the process.

The project started from a chance meeting at a conference in Italy. Lloyd and Belcher, a professor of biological engineering, were reporting on different projects they had worked on, and began discussing the possibility of a project encompassing their very different expertise. Lloyd, whose work is mostly theoretical, pointed out that the viruses Belcher works with have the right length scales to potentially support quantum effects.

In 2008, Lloyd had published a paper demonstrating that photosynthetic organisms transmit light energy efficiently because of these quantum effects. When he saw Belcher’s report on her work with engineered viruses, he wondered if that might provide a way to artificially induce a similar effect, in an effort to approach nature’s efficiency.

“I had been talking about potential systems you could use to demonstrate this effect, and Angela said, ‘We’re already making those,'” Lloyd recalls. Eventually, after much analysis, “We came up with design principles to redesign how the virus is capturing light, and get it to this quantum regime.”

Within two weeks, Belcher’s team had created their first test version of the engineered virus. Many months of work then went into perfecting the receptors and the spacings.

Once the team engineered the viruses, they were able to use laser spectroscopy and dynamical modeling to watch the light-harvesting process in action, and to demonstrate that the new viruses were indeed making use of quantum coherence to enhance the transport of excitons.

“It was really fun,” Belcher says. “A group of us who spoke different [scientific] languages worked closely together, to both make this class of organisms, and analyze the data. That’s why I’m so excited by this.”

While this initial result is essentially a proof of concept rather than a practical system, it points the way toward an approach that could lead to inexpensive and efficient solar cells or light-driven catalysis, the team says. So far, the engineered viruses collect and transport energy from incoming light, but do not yet harness it to produce power (as in solar cells) or molecules (as in photosynthesis). But this could be done by adding a reaction center, where such processing takes place, to the end of the virus where the excitons end up.

MIT has produced a video explanation of the work,

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

Enhanced energy transport in genetically engineered excitonic networks by Heechul Park, Nimrod Heldman, Patrick Rebentrost, Luigi Abbondanza, Alessandro Iagatti, Andrea Alessi, Barbara Patrizi, Mario Salvalaggio, Laura Bussotti, Masoud Mohseni, Filippo Caruso, Hannah C. Johnsen, Roberto Fusco, Paolo Foggi, Petra F. Scudo, Seth Lloyd, & Angela M. Belcher. Nature Materials (2015) doi:10.1038/nmat4448 Published online 12 October 2015

This paper is behind a paywall.

Viruses as manufacturing plants

In her January 2011 TEDx talk at Caltech (California Institute of Technology), MIT (Massachusetts Institute of Technology) Professor Angela Belcher talks about using viruses to grow batteries that don’t require toxic materials for their production or produce toxic materials themselves. It’s similar to biomimicry in that the reference point is nature but rather than trying to simulate nature using synthetic materials this work focuses on tweaking nature so that something like a virus can be used to create something new, e.g., a battery, a solar cell, etc.


A Sept. 25, 2011 article by Karen Weintraub on the BBC News website offers further insight into Belcher’s work,

Prof Belcher’s work unites the inanimate world of simple chemicals with proteins made by living creatures, a mash-up of the living and the lifeless.

She is motivated, she says, by a simple question: “How do you give life to non-living things?”

Like the abalone collecting its materials in shallow water and then laying them down like bricks in a wall, Belcher takes basic chemical elements from the natural world: carbon, calcium, silicon, zinc. Then she mixes them with simple, harmless viruses whose genes have been reprogrammed to promote random variations.

The resulting new materials just might address some of our most vexing problems.

The distinctiveness of Prof Belcher’s work, colleagues say, lies in her use of biology to synthesise new materials for such a wide range of uses, to develop an entirely new method for producing entirely novel materials.

“Her methodologies for directing and assembling materials I think will be unique,” says Yet-Ming Chiang, an MIT professor who collaborates with Prof Belcher on battery research. “I think 50 years from now, we’ll look back on biology as an important part of the toolkit in manufacturing… we’ll look back and say this is one of the fundamental tools we developed in this century.”

As I’ve been thinking about life/nonlife (in the context of human enhancement and memristors), this works offers me additional food for thought. Meanwhile, the TEDx talk and the Weintraub article point to some of the vast difference between scientists and lay people (general public). Belcher references life/nonlife quite casually, almost in passing. This could be quite disturbing to folks who believe there’s a distinct difference. The disturbances don’t stop there.

In the first place, viruses do not have a good reputation. When you add in the problems with calling your work biotechnology (as Belcher does in her TEDx talk), the stage is set for some interesting possibilities. If that isn’t enough, Belcher’s work comes perilously close to Eric Drexler’s self-assembling nano entities and the spectre of ‘grey’ or ‘green’ goo. It’s been a while since the big scares over genetically modified organisms (GMO), I wonder if scientists have forgotten or perhaps they don’t realize just how much conflicting (and often frightening) information is still being pushed at the general public. As for breaching the life/nonlife boundaries, that could be a whole other mess.

Nanoscience: the next 50 years?

Tomorrow, Jan. 15 2011, there’s going to be a Kavli Futures Symposium titled, Plenty of Room in the Middle: Nanoscience – The Next 50 Years. This a symposium is being hosted (as you may have guessed) by the Kavli Nanoscience Institute at the California Institute of Technology where (from the Jan. 12, 2011 news item on Nanowerk),

… an assembly of pioneering scientists will gather to focus on four key topics in nanoscience: atomic-scale assembly and imaging, mesoscopic quantum coherence, the “nano/bio nexus” and nanotechnology frontiers. Co-chairing the symposium are Michael Roukes, co-director of the Kavli Institute of Nanoscience at the California Institute of Technology, and IBM scientist Donald Eigler.

Unfortunately, they do not seem to be webcasting this event but there’s a transcript of a recent teleconference amongst three of the pioneering nanoscientists who will be gathering to discuss Feynman, his legacy, and the future. (The transcript is embedded in the news item on Nanowerk.)  The three scientists are:

  • IBM scientist Don Eigler
  • Angela Belcher Massachusetts Institute of Technology (MIT) materials scientist
  • David Awschalom University of California physicist

Here’s an excerpt from the transcript which gives you a preview of what they’ll be talking about tomorrow. This bit is where David Awschalom is discussing convergence in the sciences,

I believe that the broad umbrella of nanoscience is rapidly dissolving the traditional barriers between these disciplines, and maybe wiring them a bit together with the idea that now people are thinking about atoms and materials as arbitrary forms, not in the historical sense. Physicists are now using biological systems, and biologists are exploiting solid state devices and microfluidic devices within a myriad of research efforts. People are thinking much more broadly than in the past and, as Don [Eigler] says, I think it’s the discoveries in science that are driving this direction. When I look at the students who are entering the university system, they’re highly motivated by the idea of breaking down the normal barriers and focusing on the new scientific opportunities that emerge. I agree with Don. I think the idea of labeling things is wrong. This merging is going to happen very naturally. It’s already happening. For example, some researchers are thinking about photosynthesis as a quantum process, and [asking] whether photosynthesis is driven quantum mechanically in certain plants – exploring the concept of coherent energy transfer in biology. If so, it is possible to control this flow with exquisite precision. When you look in the literature, there are growing numbers of laboratories working in these cross-disciplinary areas; not because they’re suddenly interested in biology but they realize that biological systems could be tuned and engineered to explore unique scientific missions. So yes, I do believe that this merge is inevitable. I don’t think it’s going to be because of funding, or because of labeling, as Don says, but it’s where the interest is, and it where the new frontiers are in science.

I find this to be very interesting since it fits in very well with a recent presentation that MIT researchers made at a forum hosted by the American Association for the Advancement of Science (AAAS) earlier this month. From the Jan. 5, 2011 news item on Azonano,

A new model for scientific research known as “convergence” offers the potential for revolutionary advances in biomedicine and other areas of science, according to a white paper issued today by 12 leading MIT researchers.

The report, “The Third Revolution: The Convergence of the Life Sciences, Physical Sciences and Engineering,” noted the impact that convergence is already having in a broad array of fields.

Just as advances in information technology, materials, imaging, nanotechnology and related fields — coupled with advances in computing, modeling and simulation — have transformed the physical sciences, so are they are beginning to transform life science. The result is critical new biology-related fields, such as bioengineering, computational biology, synthetic biology and tissue engineering.

At the same time, biological models (understanding complex, self-arranged systems) are already transforming engineering and the physical sciences, making possible advances in biofuels, food supply, viral self assembly and much more.

What’s fascinating to me is that there doesn’t seem to any consideration of the societal implications of all this boundary crossing or convergence. Frankenfoods (genetically modified food) created a major panic because people were not comfortable with crossing certain types of boundaries. Once you take the ideas being proposed by the Kavli nanoscientists and the MIT researchers from theory to application, another dimension can open up.

Not all applications are hugely upsetting to society but some have the potential to cause havoc and they don’t necessarily have to cross boundaries. For example, computers created huge problems. I once had a technical writer tell me that she found bullet casings in some of the computerized equipment they received back from some small towns in northern British Columbia (Canada). People were afraid for their jobs. And, when I was working in the library system at the University of British Columbia, a librarian tried to sabotage the system; she didn’t use a gun or a rifle. Instead, when they were transferring information from card catalogues to online catalogues the librarian [started] taking large chunks of catalogue cards home with her, effectively hiding the information.

Stories like the one about the librarian might seem amusing now but there was genuine anguish and panic over the advent of the computer into daily life. Personally, I think the changes these nanoscientists are discussing are more profound and potentially disturbing.