Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Reversible Microlenses to Speed Chemical Detection

14.02.2006


Scientists at Georgia Tech have created technology capable of detecting trace amounts of biological or chemical agents in a matter of seconds, much faster than traditional methods, which can take hours or up to a day. The system uses reusable hydrogel microlenses so small that millions of them can fit on a one-inch-square plate. It could greatly enhance the ability of authorities responding to a biological or chemical weapons attack as well as increase the speed of medical testing. The research appears in the February 20 edition of the chemistry journal Angawandte Chemie.


"Reversible Microlenses"


On the left, a microlens is in the “on” state and ready to detect. The right shows the microlens in the “off” state after it has detected its target chemical.



The microlenses make use of the antibody-antigen binding, the same process used by the human immune system, to detect biological or chemical agents. When antibodies on the microlenses come into contact with the antigen they are set to detect, they bind, causing the lenses to swell and become less dense. By projecting an image through the tiny lenses, scientists can view this swelling as a change in the microlens’ focal length. If the projected image is normally in focus, it goes out of focus when it comes into contact with the substance.

“These are reversible, so you can use the same lenses over and over again. This is the first time someone has done this with microlenses,” said L. Andrew Lyon, associate professor in the School of Chemistry and Biochemistry at the Georgia Institute of Technology.


Lyon and colleagues tested their system on its ability to detect biotin, a B-complex vitamin. To make the two-micrometer-wide microlenses, they coated the surface of a flexible polymeric hydrogel microsphere with the antigen biotin and aminobenzophenone (ABP), a photo-cross-linking agent, which is able to chemically attach to other molecules when exposed to UV light. Adhering these microparticles on a glass substrate causes them to deform into microlenses. After binding the biotin with its antibody, researchers hit it with ultraviolet light, causing the ABP to react with the antibody, attaching it to the microlens irreversibly. The microlenses are now ready to do their job.

“When you expose the lens to a solution that contains the antigen, it will compete for the binding site on the antibody. When the antigen and antibody bind, the lens swells and become less dense, changing its focus,” said Lyon.

Once developed into a device, the microlenses’ ability to conduct rapid chemical and biological tests could lead to significant savings in healthcare costs as many blood tests could be run in a physician’s office rather than being sent to an outside lab. It could also allow authorities to rapidly detect and identify a toxic chemical in the event of a spill or terrorist attack.

Many traditional analyses using enzyme or fluorophore-labeled antibodies can take up to a day or more and require large pieces of expensive equipment. A device built with microlenses could be handheld, since standard technologies currently exist that integrate microlenses into compact optical systems.

“The beauty of this is that the microlenses are very tunable in terms of sensitivity,” said Lyon. “You can also make arrays so you can detect multiple components on one sample, allowing you to multiplex your detection. Whereas now, each separate thing that doctors look for in a blood test is a different test they have to do in the lab.”

Lyon said the next step in developing the microlens sensors is to test the technology’s performance in complex biological fluids, like blood serum.

David Terraso | EurekAlert!
Further information:
http://www.gatech.edu

More articles from Life Sciences:

nachricht In living color: Brightly-colored bacteria could be used to 'grow' paints and coatings
20.02.2018 | University of Cambridge

nachricht Computers aid discovery of new, inexpensive material to make LEDs with high color quality
20.02.2018 | University of California - San Diego

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

New tech for commercial Lithium-ion batteries finds they can be charged 5 times fast

20.02.2018 | Power and Electrical Engineering

Hidden talents: Converting heat into electricity with pencil and paper

20.02.2018 | Materials Sciences

Rare find from the deep sea

20.02.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>