Navigation Links
Super-thin membranes clear the way for chip-sized pumps
Date:10/28/2013

The ability to shrink laboratory-scale processes to automated chip-sized systems would revolutionize biotechnology and medicine. For example, inexpensive and highly portable devices that process blood samples to detect biological agents such as anthrax are needed by the U.S. military and for homeland security efforts. One of the challenges of "lab-on-a-chip" technology is the need for miniaturized pumps to move solutions through micro-channels. Electroosmotic pumps (EOPs), devices in which fluids appear to magically move through porous media in the presence of an electric field, are ideal because they can be readily miniaturized. EOPs however, require bulky, external power sources, which defeats the concept of portability. But a super-thin silicon membrane developed at the University of Rochester could now make it possible to drastically shrink the power source, paving the way for diagnostic devices the size of a credit card.

"Up until now, electroosmotic pumps have had to operate at a very high voltageabout 10 kilovolts," said James McGrath, associate professor of biomedical engineering. "Our device works in the range of one-quarter of a volt, which means it can be integrated into devices and powered with small batteries."

McGrath's research paper is being published this week by the journal Proceedings of the National Academy of Sciences.

McGrath and his team use porous nanocrystalline silicon (pnc-Si) membranes that are microscopically thinit takes more than one thousand stacked on top of each other to equal the width of a human hair. And that's what allows for a low-voltage system.

A porous membrane needs to be placed between two electrodes in order to create what's known as electroosmotic flow, which occurs when an electric field interacts with ions on a charged surface, causing fluids to move through channels. The membranes previously used in EOPs have resulted in a significant voltage drop between the electrodes, forcing engineers to begin with bulky, high-voltage power sources. The thin pnc Si membranes allow the electrodes to be placed much closer to each other, creating a much stronger electric field with a much smaller drop in voltage. As a result, a smaller power source is needed.

"Up until now, not everything associated with miniature pumps was miniaturized," said McGrath. "Our device opens the door for a tremendous number of applications."

Along with medical applications, it's been suggested that EOPs could be used to cool electronic devices. As electronic devices get smaller, components are packed more tightly, making it easier for the devices to overheat. With miniature power supplies, it may be possible to use EOPs to help cool laptops and other portable electronic devices.

McGrath said there's one other benefit to the silicon membranes. "Due to scalable fabrication methods, the nanocrystalline silicon membranes are inexpensive to make and can be easily integrated on silicon or silica-based microfluid chips."


'/>"/>

Contact: Peter Iglinski
peter.iglinski@rochester.edu
585-764-7002
University of Rochester
Source:Eurekalert  

Related biology news :

1. Researchers capture images of open channel that moves proteins across cell membranes
2. Photosynthesis: Membranes in tight corners
3. Modifications of a nanoparticle can change chemical interactions with cell membranes
4. Patel recognized with NSF Career Award for computer-modeling research on cell membranes
5. Microfluidic platform gives a clear look at a crucial step in cancer metastasis
6. Chair Mats of Glass Company Clearly Innovative Announces the Launch of 20 New Dealers in the Midwest
7. Researchers reveal the clearest new pictures of immune cells
8. Less haze in Singapore as the cause becomes clearer and more complex
9. CNIO researchers identify a new gene that is essential for nuclear reprogramming
10. U-M researchers find new way to clear cholesterol from the blood
11. Invention could make spent nuclear fuel useful for irradiation purposes
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Super-thin membranes clear the way for chip-sized pumps
(Date:3/1/2017)... -- Aware, Inc. (NASDAQ: AWRE), a leading supplier of biometrics ... has resigned, effective March 3, 2017, as co-Chief ... Treasurer of Aware citing a desire to retire.  Mr. ... the Board of Directors of Aware. ... co-President, General Counsel has been named Chief Executive Officer, ...
(Date:2/26/2017)... DALLAS , Feb. 25, 2017  Securus ... justice technology solutions for public safety, investigation, corrections ... of Recidivism and Reentry. "Too often, ... State prisons and county jails are trying to ... of inmates and friends and family members. While significant ...
(Date:2/16/2017)... FRANCISCO , Feb. 16, 2017  Genos, ... today announced that it has received Laboratory Accreditation ... CAP Accreditation is presented to laboratories that meet ... who demonstrate scientifically rigorous processes. "Genos ... excellence in laboratory practices. We,re honored to be ...
Breaking Biology News(10 mins):
(Date:3/29/2017)... ... March 29, 2017 , ... (March 29, 2017) — ... approved as an active member of the Mexican Direct Selling Association A.C. ... consumers in relationship marketing. This professional organization fosters loyal and fair competition among ...
(Date:3/29/2017)... March 29, 2017  Applied BioMath ( ... modeling to drug research and development, today ... Zymeworks Inc. for quantitative systems pharmacology (QSP) ... for the treatment of cancer. ... for GLP toxicology studies and first-in-human dose ...
(Date:3/29/2017)... ... ... On the heels of the globally recognized Rare Disease Day , ... it will manage travel services for its 500th clinical trial this month. The company, ... Europe to offer travel management services specifically for clinical trials and their sponsors, and ...
(Date:3/29/2017)... ... March 29, 2017 , ... Cancer diagnostics ... in booth 513 at the Association of Community Cancer Centers (ACCC) 43rd Annual ... , CANCERSCAPE unites key stakeholders from leading national organizations to share insights ...
Breaking Biology Technology: