Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > New particle-sorting method breaks speed records: Discovery could lead to new ways of detecting cancer cells or purifying contaminated water

This image shows an example of a rigid epoxy microfluidic device, similar to those used for the new high-throughput system, on an optical microscope.

Image: John Friedah
This image shows an example of a rigid epoxy microfluidic device, similar to those used for the new high-throughput system, on an optical microscope.

Image: John Friedah

Abstract:
Researchers compare the processing of biological fluid samples with searching for a needle in a haystack — only in this case, the haystack could be diagnostic samples, and the needle might be tumor cells present in just parts-per-million concentrations. Now, a new way of processing these samples could make such detections possible in real time, according to a team from MIT, Massachusetts General Hospital (MGH), and Harvard Medical School.

New particle-sorting method breaks speed records: Discovery could lead to new ways of detecting cancer cells or purifying contaminated water

Cambridge, MA | Posted on July 1st, 2014

The team's surprising discovery is described in a paper in the journal Nature Communications. The technique could allow cells to be sorted while hurtling through the channels of a microfluidic device at speeds faster than those of race cars, the authors say — at least 100 times faster than any existing system

Normally, fluid flowing through a narrow channel at such high velocity would break up into a chaotic, turbulent flow, making any sorting or identification of cells impossible. But the research team found ways of eliminating this turbulence and even focusing the flow, driving the particles into single file within the channel.

"If you're trying to find a needle in a haystack, it's a lot easier if the needle is right in the middle of the haystack," says co-author Gareth McKinley, the School of Engineering Professor of Teaching Innovation in MIT's Department of Mechanical Engineering. With this method, that's essentially what you get: In a process the team calls "inertio-elastic flow focusing," McKinley says, the flow itself helps concentrate the particles that are of interest. "The bigger particles go to the center first," he says.

In searching for tumor cells in a large volume of fluid — for example, in a fluid sample drained from a patient's lungs, or in peritoneal fluid — there may be millions of cells, including those from the tumor, in a volume of up to a few liters; these cells' shapes, numbers, and biophysical characteristics could make them indicators of cancer.

The researchers showed that by adjusting the flow properties of the fluid sample, they could concentrate all of the larger particles at the center of the flow. They adapted a high-speed, pulsed-laser imaging system to take snapshots of the shapes, sizes, and orientations of the particles as they fly through the device.

Ultimately, the researchers say, the work might lead to a compact, bedside device that could take a blood sample from a patient and provide diagnostic information immediately, rather than requiring processing at a lab, which can take hours or even days.

The new technique might have other uses, the researchers say. The ability to separate tiny nanoscale particles according to size at high speed "could be extremely important for a broad range of clinical applications and biological applications," says co-author Mehmet Toner of Harvard Medical School and MGH.

Toner explains that the basic concept of flow focusing in microchannels, at low-flow rates, is a very active research field, with at least 50 different groups around the world studying the basic physics of flow focusing and exploring a broad range of applications. This new use of the technique for extremely high-speed processing could unleash a similar surge of interest, he says.

In describing how a fluid moves through a channel, the key flow parameter is called the Reynolds number — a quantity that combines the speed of the flow, the size of the channel, and the viscosity of the liquid. Experimental observation shows that a fluid doesn't flow smoothly at a Reynolds number greater than about 2,400, Toner says, before breaking up into turbulence.

But the team found that by adding a minuscule amount of hyaluronic acid — a biopolymer — to the fluid, flow rates could be increased to a Reynolds number of 10,000 without introducing turbulence. Indeed, adding the polymer changes the flow properties of the fluid itself, giving rise to fluid viscoelasticity. Measuring how important this effect is in a fluid requires a new parameter, called the Weissenberg number; by understanding the relative magnitude of these two key parameters, the researchers were able to examine flow patterns that had never been studied before.

Doing so required finding a new way of making the microfluidic channels; existing soft materials used for microfluidic devices would not have withstood the high pressures associated with such flow rates. "At that kind of pressure, they would just explode," Toner says, "so we had to develop a rigid device that was still optically transparent."

In the new system, liquid can hurtle through a microfluidic channel just 50 micrometers across — about half the width of a human hair — at peak speeds of more than 400 mph, without turbulence. By using flashes of laser light just 10 billionths of a second in duration, the team was able to image the size, shape, and orientation of cells as they moved through the device and were squeezed by the effects of the fluid additive.

Hyaluronic acid is a biological derivative — it acts as a lubricant in the knee — that is harmless to biological samples, Toner says. And it turns out that at great speed, the focusing mechanism grows even more effective. "We didn't imagine that you could get focusing at such rates," McKinley says. The new system can achieve flow speeds up to 100 times greater than in existing microfluidic systems.

While the team suggests numerous possible applications in diagnostics, water purification, or even industrial separation of materials, such as for biofuel production, all such possibilities remain speculative at this point, Toner says.

Howard Stone, a professor of mechanical and aerospace engineering at Princeton University who was not involved in this research, says the work "appears original and significant." He adds, "The ability to control focusing of particles by … adding small amounts of hyaluronic acid seems flexible and very interesting. Moreover, the authors have demonstrated the effect at high Reynolds numbers and so at high speeds and flow rates. This work will be of interest to many people and is likely to find applications in several fields."

The team also included MIT graduate students Eugene Lim and Thomas Ober and five others.

####

For more information, please click here

Copyright © Massachusetts Institute of Technology

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Anousheh Ansari Wins the National Space Society's Space Pioneer Award for "Service to the Space Community" March 5th, 2015

Enhanced Graphene Components for Next Generation Racing Yacht March 5th, 2015

Get ready for NanoDays! March 5th, 2015

American Chemical Society Presidential Symposia: nanoscience, international chemistry March 5th, 2015

Videos/Movies

Pens filled with high-tech inks for do-it-yourself sensors March 3rd, 2015

Maximum Precision in 3D Printing: New complete solution makes additive manufacturing standard for microfabrication February 26th, 2015

Simulating superconducting materials with ultracold atoms: Rice physicists build superconductor analog, observe antiferromagnetic order February 23rd, 2015

Waterloo invention advances quantum computing research: New device, which will be used in labs around the world to develop quantum technologies, produces fragile entangled photons in a more efficient way February 16th, 2015

Microfluidics/Nanofluidics

Going with the flow January 16th, 2015

How bacteria control their size: By monitoring thousands of individual bacteria scientists discovered how they maintain their size from generation to generation January 6th, 2015

“Line dancing bacteria win the 2014 Dolomite and Lab on a Chip Video Competition” December 16th, 2014

Dolomite launches Mitos Dropix® Droplet Splitting System December 1st, 2014

Govt.-Legislation/Regulation/Funding/Policy

New research could lead to more efficient electrical energy storage March 4th, 2015

Energy-generating cloth could replace batteries in wearable devices March 4th, 2015

The taming of magnetic vortices: Unified theory for skyrmion-materials March 3rd, 2015

Black phosphorus is new 'wonder material' for improving optical communication March 3rd, 2015

Discoveries

Enhanced Graphene Components for Next Generation Racing Yacht March 5th, 2015

American Chemical Society Presidential Symposia: nanoscience, international chemistry March 5th, 2015

Magnetic vortices in nanodisks reveal information: Researchers from Dresden and Jülich use microwaves to read out information from smallest storage devices March 4th, 2015

CiQUS researchers obtain high-quality perovskites over large areas by a chemical method March 4th, 2015

Announcements

Anousheh Ansari Wins the National Space Society's Space Pioneer Award for "Service to the Space Community" March 5th, 2015

Enhanced Graphene Components for Next Generation Racing Yacht March 5th, 2015

Get ready for NanoDays! March 5th, 2015

American Chemical Society Presidential Symposia: nanoscience, international chemistry March 5th, 2015

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers

Strength in numbers: Researchers develop the first-ever quantum device that detects and corrects its own errors March 4th, 2015

Energy-generating cloth could replace batteries in wearable devices March 4th, 2015

Experiment and theory unite at last in debate over microbial nanowires: New model and experiments settle debate over metallic-like conductivity of microbial nanowires in bacterium March 4th, 2015

Magnetic vortices in nanodisks reveal information: Researchers from Dresden and Jülich use microwaves to read out information from smallest storage devices March 4th, 2015

Energy

CiQUS researchers obtain high-quality perovskites over large areas by a chemical method March 4th, 2015

UC research partnership explores how to best harness solar power March 2nd, 2015

Learning by eye: Silicon micro-funnels increase the efficiency of solar cells February 25th, 2015

Magnetic nanoparticles enhance performance of solar cells X-ray study points the way to higher energy yields February 25th, 2015

Water

Nanosorbents Increase Extraction, Recycling of Silver from Aqueous Solutions March 4th, 2015

Heightened Efficiency in Purification of Wastewater Using Nanomembranes March 3rd, 2015

Purification of Industrial Wastewater Using Visible-Light Sensitive Photocatalysts February 24th, 2015

Nanocomposite Membranes Used in Iran for Water Desalination, Sweetening February 16th, 2015

Industrial

Heightened Efficiency in Purification of Wastewater Using Nanomembranes March 3rd, 2015

Novel Method to Determine Optical Purity of Drug Components March 1st, 2015

In quest for better lithium-air batteries, chemists boost carbon's stability: Nanoparticle coatings improve stability, cyclability of '3DOm' carbon February 25th, 2015

Purification of Industrial Wastewater Using Visible-Light Sensitive Photocatalysts February 24th, 2015

Research partnerships

New research could lead to more efficient electrical energy storage March 4th, 2015

Cambrios and Heraeus Jointly Create New, High-Conductivity Transparent Conductors: Two Companies' Combined Products Dramatically Extend Flexible Substrate Capabilities for Next-Generation Mass-Market Technology Products March 3rd, 2015

The taming of magnetic vortices: Unified theory for skyrmion-materials March 3rd, 2015

UC research partnership explores how to best harness solar power March 2nd, 2015

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More










ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2015 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE