Researchers create method for more sensitive electrochemical sensors

Jan 17, 2013

Graphene and related materials hold promise for the future of electrochemical sensors—detectors that measure the concentration of oxygen, toxic gases, and other substances—but many applications require greater sensitivity at lower detection ranges than scientists have been able to achieve.

A Northwestern University research team and partners in India have recently developed a new method for amplifying signals in graphene oxide-based electrochemical sensors through a process called "magneto-electrochemical immunoassay." The findings could open up a new class of technologies with applications in medicine, chemistry, and engineering.

Researchers from Northwestern's McCormick School of Engineering and Applied Science, the Northwestern International Institute for Nanotechnology (IIN), the Northwestern University Atomic and Nanoscale Characterization Experimental (NUANCE) Center, and the Institute for Microbial Technology (IMTECH)-India, a national laboratory of India, contributed to the research.

A paper about the work, "Enhancing Electrochemical Detection on Graphene Oxide-CNT Nanostructured Electrodes Using Magneto-Nanobioprobes," was published November 19 in Nature Scientific Reports.

Graphene-based nanocomposite films have recently been used as an effective sensing platform for the development of electrochemical sensors and biosensors because of their unique facile surface modification characteristics and high charge mobility.

The researchers' new concept combines the advantages carbon nanotubes and reduced graphene oxide together with electrochemical bursting of magnetic into a large number of metal ions.

High sensitivity was achieved by precisely designing the nanohybrid and correlating the available with analyte concentration. The researchers used tiny encapsulated in inert coating of to make core-shell nanostructures with favorable magnetic properties of metallic iron while preventing them from oxidation or significant degradation. They were then coated with gold because of its chemical inertness and biocompatibility.

This novel immune-detection platform shows potential for rapid and sensitive screening of environmental pollutants or toxins in samples. Researchers reported the ultrahigh sensitivity of this method for a new generation of herbicide diuron and its analogues up to sub-picomolar concentration in standard water samples. The process also proved to be efficient and cost-effective: tens of thousands of screen-printed electrodes can be manufactured quite readily with low cost for such hybrid assay.

Explore further: Engineers discover new method to determine surface properties at the nanoscale

Related Stories

Scientists produce graphene using microorganisms

Mar 22, 2012

The Graphene Research Group at Toyohashi University of Technology (Japan) reports on the synthesis of graphene by reducing graphene oxide using microorganisms extracted from a local river.

Recommended for you

New 2-D quantum materials for nanoelectronics

Nov 21, 2014

Researchers at MIT say they have carried out a theoretical analysis showing that a family of two-dimensional materials exhibits exotic quantum properties that may enable a new type of nanoscale electronics.

Thin film produces new chemistry in 'nanoreactor'

Nov 19, 2014

Physicists of the University of Groningen and the FOM Foundation, led by professor Beatriz Noheda, have discovered a new manganese compound that is produced by tension in the crystal structure of terbium manganese oxide. ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.