Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Some like it hot: How to heat a 'nano bathtub' the JILA way

02.08.2010
Researchers at JILA have demonstrated the use of infrared laser light to quickly and precisely heat the water in "nano bathtubs"—tiny sample containers—for microscopy studies of the biochemistry of single molecules and nanoparticles.

Described in a new paper,* the JILA technique is faster, more controllable, and less prone to damaging expensive optics or accidentally altering chemistry than conventional methods using electric currents for bulk heating of microscope stages, optics and samples. The demonstration extends a technique used to study single living cells to the field of single-molecule microscopy.

Fast, noncontact heating of very small samples is expected to enable new types of experiments with single molecules. For example, sudden, controlled jumps in temperature could be used to activate molecular processes and observe them in real time.

JILA is jointly operated by the National Institute of Standards and Technology (NIST) and the University of Colorado at Boulder (CU).

The JILA "bathtubs" consist of about 35 picoliters (trillionths of a liter, or roughly one-thirtieth of a nanoliter) of water on a glass slide. Gently focused infrared laser light is used to heat a nanoscale column of water. By moving the laser beam, this column can be made to warm single RNA molecules attached to the slide. The samples are mounted above an inverted fluorescence microscope, used to study folding of tagged RNA molecules (See for example, "JILA Study of RNA Dynamics May Help in Drug Design," NIST Tech Beat, July 13, 2005 at http://www.nist.gov/public_affairs/techbeat/tb2005_0713.htm#JILA). The researchers simultaneously heated and observed folding of the molecules, comparing results obtained with the laser heating technique to measurements obtained with bulk heating.

The heating laser is directed at the samples from above, with the beam focused to a spot size of about 20 micrometers. The near-infrared light is just the right wavelength to excite vibrations in chemical bonds in the water molecules; the vibrations quickly turn into heat. The laser offers a much larger dynamic temperature range (20 to 90 degrees Celsius, or 68 to 194 degrees Fahrenheit) than bulk heating methods, according to the paper. In early trials, the technique controlled bathtub heating to an accuracy of half a degree Celsius in less than 20 milliseconds across a micrometer-scale sample area.

"Exact sizes of the laser beam and sample area don't matter," says NIST/JILA Fellow David Nesbitt, senior author of the paper. "What's important is having time and temperature control over volumes of fluid small enough to be able to look at single molecules."

The research is funded in part by the National Science Foundation, NIST, and the W.M. Keck Foundation initiative in RNA sciences.

* E. D. Holmstrom and D.J. Nesbitt. Real-Time Infrared Overtone Laser Control of Temperature in Picoliter H2O Samples: "Nanobathtubs" for Single Molecule Microscopy. Journal of Physical Chemistry Letters 1, pages 2264-2268. Published online: July 7, 2010

Laura Ost | EurekAlert!
Further information:
http://www.nist.gov

More articles from Life Sciences:

nachricht Nanoparticle Exposure Can Awaken Dormant Viruses in the Lungs
16.01.2017 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Cholera bacteria infect more effectively with a simple twist of shape
13.01.2017 | Princeton University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

Im Focus: Bacterial Pac Man molecule snaps at sugar

Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.

The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...

Im Focus: Newly proposed reference datasets improve weather satellite data quality

UMD, NOAA collaboration demonstrates suitability of in-orbit datasets for weather satellite calibration

"Traffic and weather, together on the hour!" blasts your local radio station, while your smartphone knows the weather halfway across the world. A network of...

Im Focus: Repairing defects in fiber-reinforced plastics more efficiently

Fiber-reinforced plastics (FRP) are frequently used in the aeronautic and automobile industry. However, the repair of workpieces made of these composite materials is often less profitable than exchanging the part. In order to increase the lifetime of FRP parts and to make them more eco-efficient, the Laser Zentrum Hannover e.V. (LZH) and the Apodius GmbH want to combine a new measuring device for fiber layer orientation with an innovative laser-based repair process.

Defects in FRP pieces may be production or operation-related. Whether or not repair is cost-effective depends on the geometry of the defective area, the tools...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

Multiregional brain on a chip

16.01.2017 | Power and Electrical Engineering

New technology enables 5-D imaging in live animals, humans

16.01.2017 | Information Technology

Researchers develop environmentally friendly soy air filter

16.01.2017 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>