Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Using gold and light to study molecules in water

01.08.2013
Researchers at EPFL can now observe biomolecule interactions in a sample of water in real time; A major step for medicine

Thanks to a new device that is the size of a human hair, it is now possible to detect molecules in a liquid solution and observe their interactions. This is of major interest for the scientific community, as there is currently no reliable way of examining both the behavior and the chemical structure of molecules in a liquid in real time.

Developed at Boston University by Hatice Altug and her student Ronen Adato, the process brings together infrared detection techniques and gold nanoparticles. It could potentially make a whole new class of measurements possible, which would be a critical step in understanding basic biological functions as well as key aspects of disease progression and treatment. "Our technology could prove useful for studying the behaviour of proteins, medicines and cells in the blood or pollutants in water", says Hatice Altug.

Now a researcher at EPFL Dr. Altug has had her results published in Nature Communications.

Like a guitar string

The device is based on a well-known detection technique called infrared absorption spectroscopy. Infrared light can already be used to detect elements: The beam excites the molecules, which start to vibrate in different ways depending on their size, composition and other properties. "It's like a guitar string vibrating differently depending on its length," explains Hatice Altug. The unique vibration of each type of molecule acts as a signature for that molecule.

This technique works very well in dry environments but not at all well in aqueous environments. "A large number of molecules need to be present for them to be detected. It's also more difficult to detect molecules in water, as when the beam goes through the solution, the water molecules vibrate as well and interfere with the target molecule's signature," explains Dr. Altug.

Using nanoparticles to capture and illuminate molecules

To get around these obstacles, the researchers have developed a system capable of isolating the target molecules and eliminating interferences.

The size of a penny, the device is made up of miniature fluidic chambers, which are covered on one side with nano-scale gold particles with surprising properties. "We cover the surface of the nanoparticles with, for example, antibodies, in order to make a specific protein or chemical stick to them," explains the researcher. "Once the solution containing the targeted elements is introduced into the chamber, the nanoparticles act as molecule catchers." This technique makes it possible to isolate the target molecules from the rest of the liquid.

But this is not the only role the nanoparticles play. They are also capable of concentrating light in nanometer-size volumes around their surface as a result of plasmonic resonance.

In the chamber, the beam doesn't need to pass through the whole solution. Instead, it is sent straight to the nanoparticle, which concentrates the light. Caught in the trap, the target molecules are the only ones that are so intensely exposed to the photons.

The reaction between the molecules and the infrared photons is extremely strong, which means they can be detected and observed very precisely. "This technique enables us to observe molecules in-situ as they react with elements in their natural environment. This could prove extremely useful for both medicine and biology," states Dr. Altug.

Use in medical research

Another advantage is that the chip is extremely compact and can be connected to microscopes already in use. "We don't need large sample sizes to conduct our analyses," says Ronen Adato.

Going forward, Hatice Altug intends to continue her research with a focus on medical applications. The first tests have been conducted with ordinary antibody molecules, and the analyses now need to be fine-tuned. "I'd really like to work with other life-science researchers, hospitals and biologists. I'm especially interested in using my method in the study of diseases, including cancer and neurological disorders, to observe the effect of certain medicines on diseased cells or to detect disease biomarkers, for example."

Pessina Laure-Anne | EurekAlert!
Further information:
http://www.epfl.ch

More articles from Life Sciences:

nachricht Flavins keep a handy helper in their pocket
25.04.2018 | University of Freiburg

nachricht Complete skin regeneration system of fish unraveled
24.04.2018 | Tokyo 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: BAM@Hannover Messe: innovative 3D printing method for space flight

At the Hannover Messe 2018, the Bundesanstalt für Materialforschung und-prüfung (BAM) will show how, in the future, astronauts could produce their own tools or spare parts in zero gravity using 3D printing. This will reduce, weight and transport costs for space missions. Visitors can experience the innovative additive manufacturing process live at the fair.

Powder-based additive manufacturing in zero gravity is the name of the project in which a component is produced by applying metallic powder layers and then...

Im Focus: Molecules Brilliantly Illuminated

Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.

Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Getting electrons to move in a semiconductor

25.04.2018 | Physics and Astronomy

Reconstructing what makes us tick

25.04.2018 | Physics and Astronomy

Cheap 3-D printer can produce self-folding materials

25.04.2018 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>