Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Rice uses light to remotely trigger biochemical reactions

Deep-sea microbes that thrive in high temperatures are key to light-activated catalysis
Since Edison’s first bulb, heat has been a mostly undesirable byproduct of light. Now researchers at Rice University are turning light into heat at the point of need, on the nanoscale, to trigger biochemical reactions remotely on demand.

The method created by the Rice labs of Michael Wong, Ramon Gonzalez and Naomi Halas and reported today in the American Chemical Society journal ACS Nano makes use of materials derived from unique microbes – thermophiles – that thrive at high temperatures but shut down at room temperature.

The Rice project led by postdoctoral fellow Matthew Blankschien and graduate student Lori Pretzer combines enzymes from these creatures with plasmonic gold nanoparticles that heat up when exposed to near-infrared light. That activates the enzymes, which are then able to carry out their functions.

This effectively allows chemical processes to happen at lower temperatures. Because heating occurs only where needed – at the surface of the nanoparticle, where it activates the enzyme – the environment stays cooler.

Blankschien thinks that’s fascinating.

“Basically, we’re getting the benefits of high-temperature manufacturing without needing a high-temperature environment,” said Blankschien, who won the Peter and Ruth Nicholas Postdoctoral Fellowship two years ago to work on these ideas. “The challenge was to keep the higher temperature at the nanoparticle, where the enzyme is activated, from affecting the environment around it.”

The technique holds great potential for industrial processes that now require heat or benefit from remote triggering with light.

“The implications are pretty exciting,” said Wong, a professor of chemical and biomolecular engineering and of chemistry. “In the chemical industry, there’s always a need for better catalytic materials so they can run reactions more inexpensively, more ‘green’ and more sustainably. You shouldn’t run through gallons of solvent to make a milligram of product, even if you happen to be able to sell it for a lot of money.”

For industry, the potential energy savings alone may make the Rice process worth investigating. “Here we’re using ‘free’ energy,” Wong said. “Instead of needing a big boiler to produce steam, you turn on an energy-efficient light bulb, like an LED. Or open a window.”

The particle at the center of the process is a gold nanorod about 10 nanometers wide and 30 long that heats up when hit with near-infrared light from a laser. The rods are just the right size and shape to react to light at around 800 nanometers. The light excites surface plasmons that ripple like water in a pool, in this case emitting energy as heat.

Halas’ Rice lab is famous for pioneering the use of gold nanoshells (a related material) to treat cancer by targeting tumors with particles that are bulk heated to kill tumors from the inside. The therapy is now in human trials.

The new research takes a somewhat different tack by heating nanoparticles draped with a model thermophilic enzyme, glucokinase, from Aeropyrum pernix. A. pernix is a microbe discovered in 1996 thriving near hot underwater vents off the coast of Japan. At around 176 degrees Fahrenheit, A. pernix degrades glucose, a process necessary to nearly every living thing. The enzyme can be heated and cooled repeatedly.

In their experiments, Blankschien and Pretzer cloned, purified and altered glucokinase enzymes so they would attach to the gold nanoparticles. The enzyme/nanoparticle complexes were then suspended in a solution and tested for glucose degradation. When the solution was heated in bulk, they found the complexes became highly active at 176 degrees, as expected.

Then the complexes were encapsulated in a gel-like bead of calcium alginate, which helps keeps the heat in but is porous enough to allow enzymes to react with materials around it. Under bulk heating, the enzymes’ performance dropped dramatically because the beads insulated the enzymes too well.

But when encapsulated complexes were illuminated by continuous, near-infrared laser light, they worked substantially better than under bulk heating while leaving the solution at near-room temperature. The researchers found the complexes robust enough for weeks of reuse.

“As far-fetched as it sounds, I think chemical companies will be interested in the idea of using light to make chemicals,” Wong said. “They’re always interested in new technologies that can help make chemical products more cheaply.”

He sees other possible uses for the new approach in the production of fuels from degradation of biomass like lignocellulose; for drug manufacture on demand – maybe from nanoparticle-infused tattoos on the body; or even for lowering blood sugar concentrations as a different way to manage diabetes.

“That we can now make these particles is great,” Wong said. “The next exciting part is in thinking about how we can deploy them.”

Ryan Huschka, a co-author of the paper, is a former Rice graduate student and now an assistant professor of chemistry at Newman University. Halas is the Stanley C. Moore Professor in Electrical and Computer Engineering, a professor of biomedical engineering, chemistry, physics and astronomy and director of Rice’s Laboratory for Nanophotonics. Gonzales is an associate professor of chemical and biomolecular engineering and also of bioengineering

The research was supported by the Peter and Ruth Nicholas Postdoctoral Fellowship Program administered by the Richard E. Smalley Institute for Nanoscale Science and Technology, the Rice University Institute of Biosciences and Bioengineering Hamill Innovations Award Program, the Rice University Faculty Initiatives Fund, the Robert A. Welch Foundation, the National Security Science and Engineering Faculty Fellowship, the Defense Threat Reduction Agency, the Air Force Office of Scientific Research and the National Science Foundation.

David Ruth | EurekAlert!
Further information:

More articles from Life Sciences:

nachricht High-arctic butterflies shrink with rising temperatures
07.10.2015 | Aarhus University

nachricht Long-term contraception in a single shot
07.10.2015 | California Institute of Technology

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Kick-off for a new era of precision astronomy

The MICADO camera, a first light instrument for the European Extremely Large Telescope (E-ELT), has entered a new phase in the project: by agreeing to a Memorandum of Understanding, the partners in Germany, France, the Netherlands, Austria, and Italy, have all confirmed their participation. Following this milestone, the project's transition into its preliminary design phase was approved at a kick-off meeting held in Vienna. Two weeks earlier, on September 18, the consortium and the European Southern Observatory (ESO), which is building the telescope, have signed the corresponding collaboration agreement.

As the first dedicated camera for the E-ELT, MICADO will equip the giant telescope with a capability for diffraction-limited imaging at near-infrared...

Im Focus: Locusts at the wheel: University of Graz investigates collision detector inspired by insect eyes

Self-driving cars will be on our streets in the foreseeable future. In Graz, research is currently dedicated to an innovative driver assistance system that takes over control if there is a danger of collision. It was nature that inspired Dr Manfred Hartbauer from the Institute of Zoology at the University of Graz: in dangerous traffic situations, migratory locusts react around ten times faster than humans. Working together with an interdisciplinary team, Hartbauer is investigating an affordable collision detector that is equipped with artificial locust eyes and can recognise potential crashes in time, during both day and night.

Inspired by insects

Im Focus: Physicists shrink particle accelerator

Prototype demonstrates feasibility of building terahertz accelerators

An interdisciplinary team of researchers has built the first prototype of a miniature particle accelerator that uses terahertz radiation instead of radio...

Im Focus: Simple detection of magnetic skyrmions

New physical effect: researchers discover a change of electrical resistance in magnetic whirls

At present, tiny magnetic whirls – so called skyrmions – are discussed as promising candidates for bits in future robust and compact data storage devices. At...

Im Focus: High-speed march through a layer of graphene

In cooperation with the Center for Nano-Optics of Georgia State University in Atlanta (USA), scientists of the Laboratory for Attosecond Physics of the Max Planck Institute of Quantum Optics and the Ludwig-Maximilians-Universität have made simulations of the processes that happen when a layer of carbon atoms is irradiated with strong laser light.

Electrons hit by strong laser pulses change their location on ultrashort timescales, i.e. within a couple of attoseconds (1 as = 10 to the minus 18 sec). In...

All Focus news of the innovation-report >>>



Event News

EHFG 2015: Securing healthcare and sustainably strengthening healthcare systems

01.10.2015 | Event News

Conference in Brussels: Tracking and Tracing the Smallest Marine Life Forms

30.09.2015 | Event News

World Alzheimer`s Day – Professor Willnow: Clearer Insights into the Development of the Disease

17.09.2015 | Event News

Latest News

NASA provides an infrared look at Hurricane Joaquin over time

08.10.2015 | Earth Sciences

Theoretical computer science provides answers to data privacy problem

08.10.2015 | Information Technology

Stellar desk in wave-like motion

08.10.2015 | Physics and Astronomy

More VideoLinks >>>