Featured Research

from universities, journals, and other organizations

Einstein's Tea Leaves Inspire New Blood Separation Technique

Date:
January 17, 2007
Source:
American Institute of Physics
Summary:
Scientists at Monash University in Australia have developed a process for rapidly and efficiently separating blood plasma at the microscopic level without any moving parts, potentially allowing doctors to do blood tests without sending samples to a laboratory.

Scientists at Monash University in Australia have developed a process for rapidly and efficiently separating blood plasma at the microscopic level without any moving parts, potentially allowing doctors to do blood tests without sending samples to a laboratory. The new method uses the same principle that causes tea leaves to accumulate at the center of the bottom in a stirred teacup, a phenomenon first explained by Einstein in the 1920s.

The research was done by Drs. Dian R. Arifin, Leslie Y. Yeo and James R. Friend, of Monash University's Micro/Nanophysics Research Laboratory in the Department of Mechanical Engineering. The researchers' findings are published in the current issue of the new open-access journal Biomicrofluidics (http://bmf.aip.org).

Separating blood plasma from red blood cells, proteins and other microscopic particles is an essential step in many common medical tests, including those for cholesterol levels, drugs in athletes, blood types in donors and glucose levels in diabetics. Current testing requires samples to be taken in a doctor's office and sent off to a laboratory and analyzed with a large centrifuge, a process that can take several days.

In the new method, a tiny amount of blood enters a fluid chamber, and a needle tip is placed close to the surface of the blood at an angle. A voltage is applied to the needle, generating ions around its tip that repel the oppositely charged ions close to it. This creates an airflow known as "ionic wind" that sweeps across the surface of the blood, causing it to circulate. The microscopic particles in the blood travel in a downward spiral because of the needle's angle relative to the surface.

When the fluid begins to circulate, one might intuitively expect the microscopic particles such as red blood cells would be pulled to the outside wall of the chamber owing to centrifugal force. But because of a phenomenon called the "tea leaf paradox," the particles are instead pulled inward near the bottom of the chamber. Einstein proposed an explanation to this phenomenon in 1926 when he noticed that tea leaves collected at the center of the bottom of a stirred teacup instead of being expelled outward.

The tiny chamber of blood, like the teacup, is a cylinder of liquid that is rotated at the top while the base remains stationary. To satisfy a zero-velocity condition at the base, an inward force near the bottom of the liquid is generated, suppressing the centrifugal force there. Thus the microscopic particles spiral inward toward the bottom of the chamber like a miniature tornado, leaving a clear layer of plasma above.

Yeo anticipates the technology could be incorporated into a chip roughly the size of a credit card. He said the devices could be produced cheaply with current manufacturing techniques -- about 50 cents per chip -- but could still be five to 10 years away from mass production.

Article: Microfluidic blood plasma separation via bulk electrohydrodynamic flows, Biomicrofluidics 1, 014103 (January-March 2007), accessible at link.aip.org/link/?bmf/1/014103


Story Source:

The above story is based on materials provided by American Institute of Physics. Note: Materials may be edited for content and length.


Cite This Page:

American Institute of Physics. "Einstein's Tea Leaves Inspire New Blood Separation Technique." ScienceDaily. ScienceDaily, 17 January 2007. <www.sciencedaily.com/releases/2007/01/070116205009.htm>.
American Institute of Physics. (2007, January 17). Einstein's Tea Leaves Inspire New Blood Separation Technique. ScienceDaily. Retrieved April 19, 2014 from www.sciencedaily.com/releases/2007/01/070116205009.htm
American Institute of Physics. "Einstein's Tea Leaves Inspire New Blood Separation Technique." ScienceDaily. www.sciencedaily.com/releases/2007/01/070116205009.htm (accessed April 19, 2014).

Share This



More Health & Medicine News

Saturday, April 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Nine-Month-Old Baby Can't Open His Mouth

Nine-Month-Old Baby Can't Open His Mouth

Newsy (Apr. 19, 2014) Nine-month-old Wyatt Scott was born with a rare disorder called congenital trismus, which prevents him from opening his mouth. Video provided by Newsy
Powered by NewsLook.com
'Holy Grail' Of Weight Loss? New Find Could Be It

'Holy Grail' Of Weight Loss? New Find Could Be It

Newsy (Apr. 18, 2014) In a potential breakthrough for future obesity treatments, scientists have used MRI scans to pinpoint brown fat in a living adult for the first time. Video provided by Newsy
Powered by NewsLook.com
Little Progress Made In Fighting Food Poisoning, CDC Says

Little Progress Made In Fighting Food Poisoning, CDC Says

Newsy (Apr. 18, 2014) A new report shows rates of two foodborne infections increased in the U.S. in recent years, while salmonella actually dropped 9 percent. Video provided by Newsy
Powered by NewsLook.com
Scientists Create Stem Cells From Adult Skin Cells

Scientists Create Stem Cells From Adult Skin Cells

Newsy (Apr. 17, 2014) The breakthrough could mean a cure for some serious diseases and even the possibility of human cloning, but it's all still a way off. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins