PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Super-thin membranes clear the way for chip-sized pumps

2013-10-29
(Press-News.org) Contact information: Peter Iglinski
peter.iglinski@rochester.edu
585-764-7002
University of Rochester
Super-thin membranes clear the way for chip-sized pumps

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 voltage—about 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 thin—it 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."



INFORMATION:



ELSE PRESS RELEASES FROM THIS DATE:

Obese women alter diets in response to additional calories from soft drinks

2013-10-29
Obese women alter diets in response to additional calories from soft drinks Obese women voluntarily reduce what they eat in response to additional soft drinks being added to their diets – a new 4 week study finds(1). 41 obese women took part in the study, co-ordinated ...

Snakes on the brain: Are primates hard-wired to see snakes?

2013-10-29
Snakes on the brain: Are primates hard-wired to see snakes? Was the evolution of high-quality vision in our ancestors driven by the threat of snakes? Work by neuroscientists in Japan and Brazil is supporting the theory originally put forward by Lynne Isbell, ...

Eliminating unexplained traffic jams

2013-10-29
Eliminating unexplained traffic jams CAMBRIDGE, MA -- Everybody's experienced it: a miserable backup on the freeway, which you think must be caused by an accident or construction, but which at some point thins out for no apparent reason. Such "traffic ...

Sun continues to emit solar flares

2013-10-29
Sun continues to emit solar flares After emitting its first significant solar flares since June 2013 earlier in the week, the sun continued to produce mid-level and significant solar flares on Oct. 27 and Oct. 28, 2013. Solar flares are powerful ...

Study challenges soil testing for potassium and the fertilizer value of potassium chloride

2013-10-29
Study challenges soil testing for potassium and the fertilizer value of potassium chloride URBANA, Ill. – In the chemical age of agriculture that began in the 1960s, potassium chloride (KCl), ...

Researchers turn to technology to discover a novel way of mapping landscapes

2013-10-29
Researchers turn to technology to discover a novel way of mapping landscapes University of Cincinnati researchers are blending technology with tradition, as they discover new and improved methods for mapping landscapes. The research is newly published in the Journal ...

OU research team finds a common bioindicator resistant to insecticides

2013-10-29
OU research team finds a common bioindicator resistant to insecticides In a novel study, a University of Oklahoma researcher and collaborators found a common bioindicator, Hyalella azteca, used to test the toxicity of water or sediment was resistant to insecticides used ...

An eye-opener: NASA sees Hurricane Raymond reborn for a brief time

2013-10-29
An eye-opener: NASA sees Hurricane Raymond reborn for a brief time Tropical Storm Raymond moved away from western Mexico and into warmer waters with less wind shear over the weekend of Oct. 26-27, where it strengthened into a hurricane again. NASA's Aqua satellite ...

NASA catches glimpse of the brief life of Southern Indian Ocean's first tropical cyclone

2013-10-29
NASA catches glimpse of the brief life of Southern Indian Ocean's first tropical cyclone The first tropical cyclone of the Southern Indian Ocean season lasted about one day. Tropical Cyclone 01S was born on Oct. 27 and by Oct. 28 had become a remnant low. The ...

Neutrons, electrons and theory reveal secrets of natural gas reserves

2013-10-29
Neutrons, electrons and theory reveal secrets of natural gas reserves Gas and oil deposits in shale have no place to hide from an Oak Ridge National Laboratory technique that provides an inside look at pores and reveals structural information potentially vital ...

LAST 30 PRESS RELEASES:

As farm jobs decline, food industry work holds steady

Kennesaw State researcher aiming to move AI beyond the cloud

Revolutionizing impedance flow cytometry with adjustable microchannel height

Treating opioid addiction in jails improves treatment engagement, reduces overdose deaths and reincarceration

Can’t sleep? Insomnia associated with accelerated brain aging

Study links teacher turnover to higher rates of student suspensions, disciplinary referrals

How harmful bacteria hijack crops

Crowded conditions muddle frogs’ mating choices

A new way to guide light, undeterred

Researchers uncover how COVID-19 may linger in cancer patients and affect treatment outcomes

Tiny metal figurines from Sardinia's Nuragic civilization in around 1,000 BC reveal extensive ancient Mediterranean metal trading networks

Natural microfibers may degrade differently to synthetic materials under simulated sunlight exposure in freshwater and seawater conditions, with implications for how such pollutants affect aquatic lif

Indian new mums report better postpartum wellbeing when their own mum acts as their primary support - while women whose mother-in-law is the primary caregiver instead report significantly lower overal

Young adult intelligence and education are correlated with socioeconomic status in midlife

Traditional and “existential” wellness vary significantly between US regions

Smartwatches detect early signs of PTSD among those watching coverage of the Oct 7 attacks in Israel

The pandemic may have influenced the trainability of dogs, as reported by their owners

The withdrawal of U.S. funding for tuberculosis could lead to up to 2.2 million additional deaths between 2025 and 2030 inclusive

A ‘universal’ therapy against the seasonal flu? Antibody cocktail targets virus weak spot

Could robots help kids conquer reading anxiety? New study from the Department of Computer Science at UChicago suggests so

UCSB-designed soft robot intubation device could save lives

Burial Site challenges stereotypes of Stone Age women and children

Protein found in the eye and blood significantly associated with cognition scores

USF study reveals how menopause impacts women’s voices – and why it matters

AI salespeople aren’t better than humans… yet

Millions of men could benefit from faster scan to diagnose prostate cancer

Simulations solve centuries-old cosmic mystery – and discover new class of ancient star systems

MIT study explains how a rare gene variant contributes to Alzheimer’s disease

Race, ethnicity, insurance payer, and pediatric cardiac arrest survival

High-intensity exercise and hippocampal integrity in adults with cannabis use disorder

[Press-News.org] Super-thin membranes clear the way for chip-sized pumps