Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers Manipulate Tiny, Floating Droplets on a Chip

10.12.2003


In an innovative study, researchers at North Carolina State University have designed a way to control the movement of microscopic droplets of liquid freely floating across centimeter-sized chips packed with electrodes. The discovery allows the performance of new types of chemical experiments on the microscale.

The breakthrough came as the researchers – Dr. Orlin D. Velev, assistant professor of chemical engineering, and two NC State doctoral students, Brian Prevo and Ketan Bhatt – learned how to circumvent friction by suspending the droplets of water inside a fluorinated oil, and then using electrical voltages to allow the liquid to hover over the electrical circuits of the chip. Switching the chip’s electrodes on and off – either manually or with the aid of a computer – lets researchers move the droplets across the oil surface to any location on the chip.

The chip also allows researchers to conduct experiments with mixed droplets, as liquids can be moved along different paths and then merged or encapsulated in oil or polymer droplets.



The discovery has wide-ranging scientific implications. Besides analyses and characterizations of chemical samples, the chip can serve as a tiny factory, Velev says, allowing researchers to mix droplets to test chemical reactions, for example, or add specific amounts of toxin to a cell to see how long it takes the cell to die. Velev is also eager to synthesize new particle materials or crystals inside liquids.

The research was published in the Dec. 4 edition of Nature.

“Moving droplets of liquid on solid surfaces as other researchers have done before us has a number of limitations,” Velev said. Other research in moving droplets on solid surfaces was stunted by friction if particles or solids were moved along the channels or solid surface of a chip. “But the freely suspended droplets on this microfluidic chip never touch solid walls and thus can act as reactors for materials synthesis or precipitation,” he said.

Velev’s interest in microfluidic chips stems from his lab’s work on growing self-assembling microwires by moving gold nanoparticles with alternating current in water, and his earlier work on using floating droplets as assembly sites for complex particles.

“Experiments and bioassays, or determinations of the presence or concentration of biological molecules, that we presently do with test tubes and beakers can now be done on the microscale. This device enlarges the scope and capabilities in the field of microfluidics, which is just a few years old,” Velev said.

The chip – which was simple and inexpensive to make, Velev says, and is reusable – has received a provisional patent, with application in place for a full patent.

The research is funded by Velev’s National Science Foundation Career Award and by an ARO-Stir grant.

Dr. Orlin Velev | NC State University
Further information:
http://www.ncsu.edu/

More articles from Information Technology:

nachricht Terahertz spectroscopy goes nano
20.10.2017 | Brown University

nachricht New software speeds origami structure designs
12.10.2017 | Georgia Institute of Technology

All articles from Information Technology >>>

The most recent press releases about innovation >>>

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

Im Focus: Salmonella as a tumour medication

HZI researchers developed a bacterial strain that can be used in cancer therapy

Salmonellae are dangerous pathogens that enter the body via contaminated food and can cause severe infections. But these bacteria are also known to target...

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

3rd Symposium on Driving Simulation

23.10.2017 | Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

 
Latest News

Single nanoparticle mapping paves the way for better nanotechnology

24.10.2017 | Physics and Astronomy

A quantum spin liquid

24.10.2017 | Physics and Astronomy

Antibiotic resistance: a strain of multidrug-resistant Escherichia coli is on the rise

24.10.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>