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 Equipping form with function
23.06.2017 | Institute of Science and Technology Austria

nachricht Can we see monkeys from space? Emerging technologies to map biodiversity
23.06.2017 | Forschungsverbund Berlin e.V.

All articles from Information Technology >>>

The most recent press releases about innovation >>>

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

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>