Featured Research

from universities, journals, and other organizations

Molecular Sieve Advances Protein Research

Date:
September 13, 2006
Source:
Massachusetts Institute Of Technology
Summary:
New MIT technology promises to speed up the accurate sorting of proteins, work that may ultimately aid in the detection and treatment of disease. Separating proteins from complex biological fluids such as blood is becoming increasingly important for understanding diseases and developing new treatments. The molecular sieve developed by MIT engineers is more precise than conventional methods and has the potential to be much faster.

This scanning electron microscopy (SEM) image shows MIT's new nanoscale molecular sieve, which consists of thousands of alternating deep (300 nanometers or billionths of a meter) and shallow (55 nanometers) regions. The deep and shallow regions act together to form energy barriers that separate proteins by size. Pores of different sizes can be engineered for different filters to capture specific proteins.
Credit: Image courtesy of Han lab

New MIT technology promises to speed up the accurate sorting of proteins, work that may ultimately aid in the detection and treatment of disease.

Separating proteins from complex biological fluids such as blood is becoming increasingly important for understanding diseases and developing new treatments. The molecular sieve developed by MIT engineers is more precise than conventional methods and has the potential to be much faster.

The team's results appear in recent issues of Physical Review Letters, the Virtual Journal of Biological Physical Research and the Virtual Journal of Nanoscale Science and Technology.

The key to the molecular sieve, which is made using microfabrication technology, is the uniform size of the nanopores through which proteins are separated from biological fluids. Millions of pores can be spread across a microchip the size of a thumbnail.

The sieve makes it possible to screen proteins by specific size and shape.

In contrast, the current technique used for separating proteins, gel electrophoresis, is time-consuming and less predictable. Pore sizes in the gels vary, and the process itself is not well understood by scientists.

"No one has been able to measure the gel pore sizes accurately," said Jongyoon Han, the Karl Van Tassel Associate Professor of Electrical Engineering and Biological Engineering at MIT. "With our nanopore system, we control the pore size precisely, so we can control the sieving process of the protein molecules."

That, in turn, means proteins can be separated more efficiently, which should help scientists learn more about these crucial molecules, said Han, who also has appointments in MIT's Research Laboratory of Electronics, Computational and Systems Biology Initiative, Center for Materials Science and Engineering and Microsystems Technology Laboratories.

Han and his team, led by Jianping Fu, a graduate student in the Department of Mechanical Engineering, have devised a sieve that is embedded into a silicon chip. A biological sample containing proteins is put through the sieve for separation.

The sieving process is based on a theoretical model known as the Ogston sieving mechanism. In the model, proteins move through deep and shallow regions that act together to form energy barriers. These barriers separate proteins by size. The smaller proteins go through more quickly, followed by increasingly larger proteins, with the largest passing through last.

Once the proteins are separated, scientists can isolate and capture the proteins of interest. These include the "biomarker" proteins that are present when the body has a disease. By studying changes in these biomarkers, researchers can identify disease early on, even before symptoms show up, and potentially develop new treatments.

To date, the Ogston sieving model has been used to explain gel electrophoresis, even though no one has been able to unequivocally confirm this model in gel-based experiments. The MIT researchers were, however, able to confirm Ogston sieving in the nanopore sieves.

"This is the first time anyone was able to experimentally confirm this theoretical idea behind molecular sieving, which has been used for more than 50 years," Han said. "We can precisely control the pore size, so we can do better engineering. We can change the pore shape and engineer a better separation system." The sieve structure is based on work Han did earlier at Cornell University with large strands of DNA.

The performance of the researchers' current one-dimensional sieves matches the state-of-the-art speed of one-dimensional gels, but Han said the sieve's performance can be improved greatly.

"This device can replace gels and give us an ideal physical platform to investigate Ogston sieving," Fu said. The new sieves also potentially could be used to replace 2D gels in the process of discovering disease biomarkers, as well as to learn more about disease.

Juhwan Yoo, a Caltech undergraduate, also participated in the research as a summer visiting student. Funding came from the National Science Foundation, the National Institutes of Health and the Singapore-MIT Alliance.


Story Source:

The above story is based on materials provided by Massachusetts Institute Of Technology. Note: Materials may be edited for content and length.


Cite This Page:

Massachusetts Institute Of Technology. "Molecular Sieve Advances Protein Research." ScienceDaily. ScienceDaily, 13 September 2006. <www.sciencedaily.com/releases/2006/09/060912225719.htm>.
Massachusetts Institute Of Technology. (2006, September 13). Molecular Sieve Advances Protein Research. ScienceDaily. Retrieved August 20, 2014 from www.sciencedaily.com/releases/2006/09/060912225719.htm
Massachusetts Institute Of Technology. "Molecular Sieve Advances Protein Research." ScienceDaily. www.sciencedaily.com/releases/2006/09/060912225719.htm (accessed August 20, 2014).

Share This




More Matter & Energy News

Wednesday, August 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Flower Power! Dandelions Make Car Tires?

Flower Power! Dandelions Make Car Tires?

Reuters - Business Video Online (Aug. 20, 2014) Forget rolling on rubber, could car drivers soon be traveling on tires made from dandelions? Teams of scientists are racing to breed a type of the yellow flower whose taproot has a milky fluid with tire-grade rubber particles in it. As Joanna Partridge reports, global tire makers are investing millions in research into a new tire source. Video provided by Reuters
Powered by NewsLook.com
Awesome New Camouflage Sheet Was Inspired By Octopus Skin

Awesome New Camouflage Sheet Was Inspired By Octopus Skin

Newsy (Aug. 19, 2014) Scientists have developed a new device that mimics the way octopuses blend in with their surroundings to hide from dangerous predators. Video provided by Newsy
Powered by NewsLook.com
Researcher Testing on-Field Concussion Scanners

Researcher Testing on-Field Concussion Scanners

AP (Aug. 19, 2014) Four Texas high school football programs are trying out an experimental system designed to diagnose concussions on the field. The technology is in response to growing concern over head trauma in America's most watched sport. (Aug. 19) Video provided by AP
Powered by NewsLook.com
Green Power Blooms as Japan Unveils 'hydrangea Solar Cell'

Green Power Blooms as Japan Unveils 'hydrangea Solar Cell'

AFP (Aug. 19, 2014) A solar cell that resembles a flower is offering a new take on green energy in Japan, where one scientist is searching for renewables that look good. Duration: 01:29 Video provided by AFP
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