Laser Lights and Viruses: Novel Additions to Biosensors

New biosensors use suits of light and virus-filled fibers for accurate and timely detection to improve safety.

Researchers funded by the National Science Foundation (NSF) are creating a new biosensor that uses laser light and engineered viruses, created with advanced manufacturing techniques, to more accurately detect the smallest amounts possible of biological molecules in our food, water or blood.

Health tests conducted for pregnancy and blood sugar involve putting a drop of fluid on a test strip which acts as a simple biosensor, a device that detects chemicals with the help of biological molecules such as proteins or enzymes. The devices available today are limited in scope and can sometimes be imprecise and time-consuming. Detecting trace amounts of contaminants or medical imbalances sooner could help safeguard against harm.

The new biosensors known as whispering gallery mode resonators are based on two different mechanisms. The first, the mechanism of laser light, amplifies the detection of single particle. Whispering galleries that involve sound have been around for a while; however, whispering galleries of light have proven to be more novel.

These galleries of light work much the same way as those that involve sound, with waves of photons traveling within a circular space, or cavity. Any particles within these cavities encounter the waves thousands to millions of times, changing the light in subtle ways that researchers can detect according to the shape and makeup of the cavity.

Another technique, known as electrospinning, creates long, hair-like fibers made of plastic, metal or ceramics. This technique, interestingly enough, involves viruses.

The fiber-making process is comparable to the process of making cotton candy. A drop of liquid (after one applies electrical fields for spinning) results in a long fiber. This process is relatively straightforward, allowing these fibers to be made quickly and cheaply. These fibers need to be perfectly smooth to insert the viruses that interact with the biological molecules the engineers want to detect. Different types of viruses inserted during the spinning will enable the sensors to detect different kinds of molecules. For example, one fiber might detect glucose while another senses cholesterol. Preliminary tests show the viruses hold up quite well to the electrospinning process, but there is yet some research to be done to refine the process.

Thanks to these technologies, biosensors of the future may no longer be in cardboard boxes, but in fibers woven into clothes.

 

For more information please visit:

http://www.nsf.gov

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