Featured Research

from universities, journals, and other organizations

New type of biosensor is fast, super-sensitive

Date:
May 31, 2012
Source:
University of New South Wales
Summary:
A whole new class of biosensor that can detect exceptionally small traces of contaminants in liquids in just 40 minutes has now been developed. Known as a biochemiresistor, it meets a long-standing challenge to create a sensor that is not only super-sensitive to the presence of chemical compounds but responds quickly. It has countless potential uses for detecting drugs, toxins and pesticides for biomedical or environmental analysis.

Schematic: Magnets are used to assemble nanoparticles, coated with antibodies to enrofloxacin, between two electrodes: when antibodies leave the nanoparticles the electrical resistance falls.
Credit: Image courtesy of University of New South Wales

A whole new class of biosensor that can detect exceptionally small traces of contaminants in liquids in just 40 minutes has been developed by a UNSW-led team of researchers.

Known as a biochemiresistor, it meets a long-standing challenge to create a sensor that is not only super-sensitive to the presence of chemical compounds but responds quickly. It has countless potential uses for detecting drugs, toxins and pesticides for biomedical or environmental analysis.

In a paper published in the chemistry journal Angewandte Chemie the researchers describe how they successfully tested the new sensor by detecting tiny traces in milk of the veterinary antibiotic enrofloxacin. The journal has singled out the study for attention as a "Very Important Paper." Only 5% of papers published by the journal are so designated.

"Enrofloxacin is an antibiotic used in the agricultural industry that can be transferred to the food chain," notes co-author Scientia Professor Justin Gooding, of the UNSW School of Chemistry and the Australian Centre for Nanomedicine.

"Our biochemiresistor was able to detect enrofloxacin in neat milk in 40 minutes, at level as low as one nanogram in a litre of milk. To put that number in perspective, a nanogram is a billionth of a gram and is the mass of a single cell.

"While that is impressive enough, the sensor is a general concept that can be widely applied across many different fields."

A biosensor is a portable analytical device that uses biological molecules to detect selectively just one compound within a mix of many others. Small biosensors are already in daily use testing the safety of drinking water, for checking diabetic blood-sugar levels and for pregnancy tests

The biochemiresistor uses gold-coated magnetic nanoparticles modified with antibodies that are selective for the chemical constituent -- or analyte -- of interest. The nanoparticles are dispersed into the sample for analysis and if the analyte is present some of the antibodies detach from the nanoparticles.

Using a magnet, the nanoparticles are then assembled into a film between two electrodes and the electrical resistance is measured. The more analyte is present, the more antibodies leave the nanoparticles and the lower the resistance in the nanoparticle film.

"This new type of biosensor is rapid in response because the magnetic nanoparticle biosensors go and get the analyte rather than the usual approach of waiting for the analyte to find the sensing surface," says Gooding.

"The biochemiresistor is also more sensitive than the usual biosensor because, as the nanoparticles are dispersed throughout the sample, the entire sample is analysed, not just a small portion of the solution."

The study's lead author is Leo M.H. Lai. The team included other researchers from the Australian Centre for NanoMedicine and the former ARC Centre of Excellence for Functional Nanomaterials at UNSW.


Story Source:

The above story is based on materials provided by University of New South Wales. The original article was written by Bob Beale. Note: Materials may be edited for content and length.


Journal Reference:

  1. Leo M. H. Lai, Ian Y. Goon, Kyloon Chuah, May Lim, Filip Braet, Rose Amal, J. Justin Gooding. The Biochemiresistor: An Ultrasensitive Biosensor for Small Organic Molecules. Angewandte Chemie International Edition, 2012; DOI: 10.1002/anie.201202350

Cite This Page:

University of New South Wales. "New type of biosensor is fast, super-sensitive." ScienceDaily. ScienceDaily, 31 May 2012. <www.sciencedaily.com/releases/2012/05/120531102209.htm>.
University of New South Wales. (2012, May 31). New type of biosensor is fast, super-sensitive. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2012/05/120531102209.htm
University of New South Wales. "New type of biosensor is fast, super-sensitive." ScienceDaily. www.sciencedaily.com/releases/2012/05/120531102209.htm (accessed July 24, 2014).

Share This




More Matter & Energy News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Robot Parking Valet Creates Stress-Free Travel

Robot Parking Valet Creates Stress-Free Travel

AP (July 23, 2014) 'Ray' the robotic parking valet at Dusseldorf Airport in Germany lets travelers to avoid the hassle of finding a parking spot before heading to the check-in desk. (July 23) Video provided by AP
Powered by NewsLook.com
Boeing Ups Outlook on 52% Profit Jump

Boeing Ups Outlook on 52% Profit Jump

Reuters - Business Video Online (July 23, 2014) Commercial aircraft deliveries rose seven percent at Boeing, prompting the aerospace company to boost full-year profit guidance- though quarterly revenues missed analyst estimates. Bobbi Rebell reports. Video provided by Reuters
Powered by NewsLook.com
Europe's Car Market on the Rebound?

Europe's Car Market on the Rebound?

Reuters - Business Video Online (July 23, 2014) Daimler kicks off a round of second-quarter earnings results from Europe's top carmakers with a healthy set of numbers - prompting hopes that stronger sales in Europe will counter weakness in emerging markets. Hayley Platt reports. Video provided by Reuters
Powered by NewsLook.com
9/11 Commission Members Warn of Terror "fatigue" Among American Public

9/11 Commission Members Warn of Terror "fatigue" Among American Public

Reuters - US Online Video (July 22, 2014) Ten years after releasing its initial report, members of the 9/11 Commission warn of the "waning sense of urgency" in combating terrorists attacks. Mana Rabiee reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins