Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Electromagnetic Miniatures

09.10.2006
Simultaneous production of microchannels with parallel, electrically conducting metal wires

Magnetic components that can be controlled by the application of an external electric field are useful in many different applications. They can serve as microfluidic pumps, mixers, or valves in miniature lab-on-chip systems, or they can help in sorting and arranging magnetic particles. Biochemistry and cellular biology in particular benefit from many possible uses: for example, antibodies or other ligands that bind to individual biomolecules or to surface structures of cells can be coupled to magnetic beads in order to recognize and bind to their specific bonding partner even in complex mixtures. They can subsequently be fished out of the mixture with an electromagnet.

Electromagnets have an additional advantage over permanent magnets: they can easily be switched on and off with an electric current. Also, the field strength can be adjusted to the desired value and can be changed as required. However, electromagnets do have the disadvantage of generating weaker magnetic fields, meaning that they must be very close to the place where they are to be used.

G. M. Whitesides and his co-workers at Harvard University in Cambridge, USA, have now developed an uncomplicated method for producing a microfluidic channel along with two metal cables parallel to it and only 10 µm away. First, a structure consisting of a 40-µm-wide and 40-µm-deep inner channel between two 120-µm-wide and 40-µm-deep outer channels was lithographically engraved into a polydimethylsiloxane resin. Treatment with 3-mercaptopropyltrimethoxysilane silanized the surfaces of the outer channels. This allowed them to be coated with molten solder that was poured into the heated forms in the next step. Upon cooling, the liquid metal solidified, forming two stable metal cables to the left and right of the inner channel. Application of an electrical field to these two wires generates magnetic fields of up to 2.8 mT within the central channel.

... more about:
»Magnetic »magnetic field

It was also possible to steer magnetic spheres through the channel: the scientists again made a channel with parallel wires on either side, but this time the channel forked after a few millimeters. A suspension of magnetic spheres flowed through the channel. If current was allowed to flow through wire on the right, the spheres flowed to the right as they reached the fork, and vice versa.

George M. Whitesides | EurekAlert!
Further information:
http://www.gmwgroup.harvard.edu

Further reports about: Magnetic magnetic field

More articles from Life Sciences:

nachricht Cancer diagnosis: no more needles?
25.05.2018 | Christian-Albrechts-Universität zu Kiel

nachricht Less is more? Gene switch for healthy aging found
25.05.2018 | Leibniz-Institut für Alternsforschung - Fritz-Lipmann-Institut e.V. (FLI)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Powerful IT security for the car of the future – research alliance develops new approaches

The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.

Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

In focus: Climate adapted plants

25.05.2018 | Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

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

13.04.2018 | Event News

 
Latest News

In focus: Climate adapted plants

25.05.2018 | Event News

Flow probes from the 3D printer

25.05.2018 | Machine Engineering

Less is more? Gene switch for healthy aging found

25.05.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>