Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Tiny 'speed bump' device could sort cancer cells

13.06.2012
In life, we sort soiled laundry from clean; ripe fruit from rotten. Two Johns Hopkins engineers say they have found an easy way to use gravity or simple forces to similarly sort microscopic particles and bits of biological matter -- including circulating tumor cells.

In the May 25 online issue of Physical Review Letters, German Drazer, an assistant professor of chemical and biomolecular engineering, and his doctoral student, Jorge A. Bernate, reported that they have developed a lab-on-chip platform, also known as a microfluidic device, that can sort particles, cells or other tiny matter by physical means such as gravity.


In an illustration, magnetically labeled circulating tumor cells (shown as yellow spheres) travel with red and white blood cells and platelets over an array of slanted ramps in the device. The ramps act as speed bumps, slowing the tumor cells. As the tumor cells slow, the flow carries them along the length of the ramp, causing lateral displacement. After the tumor cells traverse an array of these ramps, they have sufficiently been displaced and can be continuously isolated from other cells in the sample. Credit: Martin Rietveld

By moving a liquid over a series of micron-scale high diagonal ramps -- similar to speed bumps on a road -- the device causes microscopic material to separate into discrete categories, based on weight, size or other factors, the team reported.

The process described in the journal article could be used to produce a medical diagnostic tool, the Whiting School of Engineering researchers say. "The ultimate goal is to develop a simple device that can be used in routine checkups by health care providers," said doctoral student Bernate, who is lead author on the paper. "It could be used to detect the handful of circulating tumor cells that have managed to survive among billions of normal blood cells. This could save millions of lives."

Ideally, these cancer cells in the bloodstream could be detected and targeted for treatment before they've had a chance to metastasize, or spread cancer elsewhere. Detection at early stages of cancer is critical for successful treatment.

How does this sorting process occur? Bernate explained that inside the microfluidic device, particles and cells suspended in liquid flow along a "highway" that has speed-bump-like obstacles positioned diagonally, instead of perpendicular to the path. The speed bumps differ in height, depending on the application.

"As different particles are driven over these diagonal speed bumps, heavier ones have a harder time getting over than the lighter ones," the doctoral student said. When the particles cannot get over the ramp, they begin to change course and travel diagonally along the length of the obstacle. As the process continues, particles end up fanning out in different directions.

"After the particles cross this section of the 'highway,'" Bernate said, "they end up in different 'lanes' and can take different 'exits,' which allows for their continuous separation."

Gravity is not the only way to slow down and sort particles as they attempt to traverse the speed bumps. "Particles with an electrical charge or that are magnetic may also find it hard to go up over the obstacles in the presence of an electric or magnetic field," Bernate said. For example, cancer cells could be "weighted down" with magnetic beads and then sorted in a device with a magnetic field.

The ability to sort and separate things at the micro- and nanoscale is important in many industries, ranging from solar power to bio-security. But Bernate said that a medical application is likely to be the most promising immediate use for the device.

He is slated to complete his doctoral studies this summer, but until then, Bernate will continue to collaborate with researchers in the lab of Konstantinos Konstantopoulos, professor and chair of the Department of Chemical and Biomolecular Engineering, and with colleagues at InterUniversity Microelectronics Center, IMEC, in Belgium. In 2011, Bernate spent 10 weeks at IMEC in a program hosted by Johns Hopkins' Institute for NanoBioTechnology and funded by the National Science Foundation.

His doctoral adviser, Drazer, said, the research described in the new journal article eventually led Jorge down the path at IMEC to develop a device that can easily sort whole blood into its components. A provisional patent has been filed for this device.

The research by Bernate and Drazer was funded in part by the National Science Foundation and the National Institutes of Health.

Illustrations and short video available; contact Mary Spiro or Phil Sneiderman.

Related links:

German Drazer's Web page:
http://microfluidics.jhu.edu/
Department of Chemical and Biomolecular Engineering:
http://www.jhu.edu/chembe/
Note: Video at
http://youtu.be/kswk6qkVJcE

Mary Spiro | EurekAlert!
Further information:
http://www.jhu.edu

More articles from Life Sciences:

nachricht Solving the efficiency of Gram-negative bacteria
22.03.2019 | Harvard University

nachricht Bacteria bide their time when antibiotics attack
22.03.2019 | Rice University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The taming of the light screw

DESY and MPSD scientists create high-order harmonics from solids with controlled polarization states, taking advantage of both crystal symmetry and attosecond electronic dynamics. The newly demonstrated technique might find intriguing applications in petahertz electronics and for spectroscopic studies of novel quantum materials.

The nonlinear process of high-order harmonic generation (HHG) in gases is one of the cornerstones of attosecond science (an attosecond is a billionth of a...

Im Focus: Magnetic micro-boats

Nano- and microtechnology are promising candidates not only for medical applications such as drug delivery but also for the creation of little robots or flexible integrated sensors. Scientists from the Max Planck Institute for Polymer Research (MPI-P) have created magnetic microparticles, with a newly developed method, that could pave the way for building micro-motors or guiding drugs in the human body to a target, like a tumor. The preparation of such structures as well as their remote-control can be regulated using magnetic fields and therefore can find application in an array of domains.

The magnetic properties of a material control how this material responds to the presence of a magnetic field. Iron oxide is the main component of rust but also...

Im Focus: Self-healing coating made of corn starch makes small scratches disappear through heat

Due to the special arrangement of its molecules, a new coating made of corn starch is able to repair small scratches by itself through heat: The cross-linking via ring-shaped molecules makes the material mobile, so that it compensates for the scratches and these disappear again.

Superficial micro-scratches on the car body or on other high-gloss surfaces are harmless, but annoying. Especially in the luxury segment such surfaces are...

Im Focus: Stellar cartography

The Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in Arizona released its first image of the surface magnetic field of another star. In a paper in the European journal Astronomy & Astrophysics, the PEPSI team presents a Zeeman- Doppler-Image of the surface of the magnetically active star II Pegasi.

A special technique allows astronomers to resolve the surfaces of faraway stars. Those are otherwise only seen as point sources, even in the largest telescopes...

Im Focus: Heading towards a tsunami of light

Researchers at Chalmers University of Technology and the University of Gothenburg, Sweden, have proposed a way to create a completely new source of radiation. Ultra-intense light pulses consist of the motion of a single wave and can be described as a tsunami of light. The strong wave can be used to study interactions between matter and light in a unique way. Their research is now published in the scientific journal Physical Review Letters.

"This source of radiation lets us look at reality through a new angle - it is like twisting a mirror and discovering something completely different," says...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Modelica Conference with 330 visitors from 21 countries at OTH Regensburg

11.03.2019 | Event News

Selection Completed: 580 Young Scientists from 88 Countries at the Lindau Nobel Laureate Meeting

01.03.2019 | Event News

LightMAT 2019 – 3rd International Conference on Light Materials – Science and Technology

28.02.2019 | Event News

 
Latest News

Solving the efficiency of Gram-negative bacteria

22.03.2019 | Life Sciences

Bacteria bide their time when antibiotics attack

22.03.2019 | Life Sciences

Open source software helps researchers extract key insights from huge sensor datasets

22.03.2019 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>