Science & Enterprise subscription

Follow us on Twitter

  • Don't let the perfect be the enemy of the good ...
    about 19 hours ago
  • Among the tech giants, Apple is the most aggressive in acquiring start-ups developing A.I. applications over the pa…
    about 1 day ago
  • New post on Science and Enterprise: Infographic – Apple Leads in A.I. Acquistions #Science #Business
    about 1 day ago
  • HBCUs still hand out more bachelor's degrees in STEM fields to Blacks than traditionally white institutions, but no…
    about 2 days ago
  • Special to Science and Enterprise ... HBCUs Still Putting Blacks in STEM by @crparks3…
    about 2 days ago

Please share Science & Enterprise

Nanotech Sensor Detects Glucose for Diabetes Testing

Color-enhanced scanning electron microscope image of nanosheets resembling tiny rose petals. (Jeff Goecker, Purdue University)

Color-enhanced scanning electron microscope image of nanosheets resembling tiny rose petals. (Jeff Goecker, Purdue University)

Researchers at Purdue University in Indiana created a non-invasive biosensor that detects minute concentrations of glucose in saliva, tears, and urine. The team at Purdue’s Birck Nanotechnology Center published its findings this week in the journal Advanced Functional Materials (paid subscription required).

The sensor has three main parts: layers of nanosheets resembling tiny rose petals made of a material called graphene, platinum nanoparticles, and the enzyme glucose oxidase. Graphene is a single-atom-thick film of carbon.

Each petal has a few layers of stacked graphene, with the edges of the petals configured as dangling, incomplete chemical bonds. These defects in the petal edges are by design, since they provide the locations where platinum nanoparticles can attach.

Electrodes are formed when the petals on nanosheets combine with the platinum nanoparticles. The glucose oxidase enzyme then attaches to the platinum nanoparticles. When glucose is detected, the enzyme converts the glucose to peroxide, which generates a signal on the electrode.

The biosensor exhibited a high sensitivity to glucose, which enables the device to detect glucose in minute quantities in bodily fluids such as tears, saliva, and urine — that can be sampled non-invasively —  as well as blood, which is the current medium for glucose measurement. “Because it can detect glucose in the saliva and tears,” says the journal article’s first author Jonathan Claussen now with the U.S. Naval Research Laboratory, “it’s a platform that might eventually help to eliminate or reduce the frequency of using pinpricks for diabetes testing.”

The sensor, say the authors, is able to distinguish between glucose and signals from other compounds commonly found in the blood that can cause interference, such as uric acid, ascorbic acid, and acetaminophen. Unlike glucose, these compounds can generate an electrical signal without the presence of an enzyme.

The sensor also uses a simple construction process, unlike other biosensors based on nanotechnology. “Typically, when you want to make a nanostructured biosensor you have to use a lot of processing steps before you reach the final biosensor product,” says doctoral student and co-author Anurag Kumar, which “involves lithography, chemical processing, etching and other steps.” Kumar notes that the petals “can be grown on just about any surface, and we don’t need to use any of these steps, so it could be ideal for commercialization.”

Claussen adds that the glucose oxidase enzyme on the current biosensor tests for glucose, but the technology can be adapted to diagnose other disorders. “But we could just swap out that enzyme with, for example, glutemate oxidase, to measure the neurotransmitter glutamate to test for Parkinson’s and Alzheimer’s, or ethanol oxidase to monitor alcohol levels for a breathalyzer,” says Claussen. “It’s very versatile, fast, and portable.”

Read more:

*     *     *

Please share Science & Enterprise ...

Comments are closed.