Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

'Micro-boxes' of water used to study single molecules

24.07.2006
Researchers at the National Institute of Standards and Technology (NIST) have demonstrated the use of water droplets as minuscule "boxes" for small numbers of biomolecules.

The unusually simple containment method may enable easier experiments on single molecule dynamics and perhaps lead to the development of molecule-sorting devices that might be used for medical screening or biotechnology research. The work was reported in the July 3 issue of Applied Physics Letters.


Prodded by optical tweezers, two "hydrosomes" move together and fuse to mix their contents, in an experiment using water droplets as minuscule boxes for manipulating small numbers of biomolecules for nanobiochemistry. Credit: NIST

The NIST team creates the boxes by briefly shaking a mixture of water, the biomolecules to be studied, and a fluorocarbon medium. Water droplets form in the oily fluorocarbon and naturally encapsulate one to several biomolecules. The researchers then watch through a microscope while using infrared lasers as "optical tweezers" to manipulate and combine the droplets (dubbed "hydrosomes") inside a tiny chamber on a slide.

A green laser is then used to excite the molecules in individual droplets, and the light emissions over several seconds are analyzed to count the molecules and observe other phenomena. The researchers use two sets of optical tweezers to move droplets together to fuse them and mix their contents (see accompanying video). The team demonstrated the technique by trapping and manipulating droplets encapsulating various molecules (including a delicate protein that survived the shaking process), detecting the fluorescence signal from dye and protein molecules, and observing the transfer of energy from one end of a specially treated DNA molecule to the other.

Water offers several advantages over other methods for containing single molecules, such as attaching them to surfaces or placing them inside liposomes (artificial cells). The water droplets can be held far from any surface that might interfere, can readily encapsulate biomolecules (which prefer being in water as opposed to the fluorocarbon medium), and can readily fuse together to mix molecules or rapidly change their chemical environment. The water droplets currently average about 300 nanometers in diameter and contain volumes measured in quadrillionths of liters; research is continuing to improve methods for controlling droplet size for different applications.

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

More articles from Physics and Astronomy:

nachricht Hope to discover sure signs of life on Mars? New research says look for the element vanadium
22.09.2017 | University of Kansas

nachricht Calculating quietness
22.09.2017 | Forschungszentrum MATHEON ECMath

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

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

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Rainbow colors reveal cell history: Uncovering β-cell heterogeneity

22.09.2017 | Life Sciences

Penn first in world to treat patient with new radiation technology

22.09.2017 | Medical Engineering

Calculating quietness

22.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>