Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A new portable biosensor detects traces of contaminants in food more quickly and more cheaply

21.05.2007
Scientists at the Universitat Autònoma de Barcelona (UAB), in cooperation with the CSIC, have developed a new electro-chemical biosensor which detects the presence, in food, of very small amounts of atrazine –one of the most widely used herbicides in agriculture and which also has very long lasting effects on the environment- as well as antibiotics in food.

The biosensor is faster, more portable and economic than the expensive laboratory methods which are used to detect contaminants, while having a very similar sensitivity. The system has been tested successfully to detect pesticides in samples of drinking water and commercial orange juice, as well as to detect traces of antibiotics in cow’s milk.

The agricultural use of atrazine, and other herbicides based on a chemical substance called triazine, often causes contamination both of underground water and overground water. For this reason food safety agencies have established control measures to prevent these pesticides entering the food chain. Similarly, antibiotics used to treat bacterial infections in domestic animals, such as the case of sulphanilamides in cattle, and even those used to improve growth in farm animals, may contaminate food and be harmful for people. The European Community has established upper limits for the presence of traces of pesticides and antibiotics in food, but the control of these limits is carried out in laboratories with expensive, slow and bulky equipment.

The sensor developed by scientists at the UAB and the CSIC will allow the detection of doses of atrazine at levels of 0.006 micrograms per litre, much lower than the maximum concentrations allowed by European regulations (0.1 micrograms per litre), and this can be done more quickly and cheaply than is the case of the chromatographs which are used today in food safety laboratories. As regards the detection of antibiotics, the sensor has a sensitivity of 1 microgram per litre for whole milk, while the legislation allows a maximum of 100 micrograms per litre.

Due to the ease of use of this sensor and its portability, the technique can be used in situ for quantitative analysis of the presence of atrazine, as well as that of other herbicides, in food and water samples outside the laboratory. The sensor can be easily prepared by means of a process that can be extended on an industrial scale to allow the manufacture of large quantities at a very low cost, and may even be made for personal, disposable use .

The chemical mechanism to detect contaminants in a sample is very similar to that used by the immune system to identify a virus or bacteria in the body. The organism attacks an infection by generating antibodies which hook onto, for example, a specific type of virus. Hence the virus is identified and may be eliminated. In the case of the sensors, specific antibodies for atrazine have been used (in the case of

pesticides) and for sulphanilamide (in the case of identifying antibiotics). Once the antibodies hook onto the contaminating particles they are attracted to the surface of a transductor which converts the contact with the antibodies into electrical signals. By measuring these electric signals the device can determine the concentration of contaminants in the sample.

According to Isabel Pividori, researcher at the UAB Sensors and Biosensors Group and co-director of the study, “due to their characteristics, such as their ability to carry out measurements in the field, the biosensors are analytical tools which have numerous applications in the agro food industry, and can be used as an alarm for the rapid detection of ‘risk’ of contamination in practices based on Risk and Critical Control Point Analysis”.

The research has been undertaken jointly by the professor of the Department of Chemistry, Salvador Alegret and the doctoral student Emanuela Zacco, and has counted on the participation of the Applied Molecular Receptor Group at the Institute of Chemical and Environmental Research in (CSIC), headed by Maria Pilar Marco. The results have recently been published in the journals Analytical Chemistry and Biosensors and Bioelectronics.

Octavi López Coronado | alfa
Further information:
http://www.uab.es

More articles from Agricultural and Forestry Science:

nachricht Cereals use chemical defenses in a multifunctional manner against different herbivores
06.12.2018 | Max-Planck-Institut für chemische Ökologie

nachricht Can rice filter water from ag fields?
05.12.2018 | American Society of Agronomy

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

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

Im Focus: Topological material switched off and on for the first time

Key advance for future topological transistors

Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...

Im Focus: Researchers develop method to transfer entire 2D circuits to any smooth surface

What if a sensor sensing a thing could be part of the thing itself? Rice University engineers believe they have a two-dimensional solution to do just that.

Rice engineers led by materials scientists Pulickel Ajayan and Jun Lou have developed a method to make atom-flat sensors that seamlessly integrate with devices...

Im Focus: Three components on one chip

Scientists at the University of Stuttgart and the Karlsruhe Institute of Technology (KIT) succeed in important further development on the way to quantum Computers.

Quantum computers one day should be able to solve certain computing problems much faster than a classical computer. One of the most promising approaches is...

Im Focus: Substitute for rare earth metal oxides

New Project SNAPSTER: Novel luminescent materials by encapsulating phosphorescent metal clusters with organic liquid crystals

Nowadays energy conversion in lighting and optoelectronic devices requires the use of rare earth oxides.

Im Focus: A bit of a stretch... material that thickens as it's pulled

Scientists have discovered the first synthetic material that becomes thicker - at the molecular level - as it is stretched.

Researchers led by Dr Devesh Mistry from the University of Leeds discovered a new non-porous material that has unique and inherent "auxetic" stretching...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

Expert Panel on the Future of HPC in Engineering

03.12.2018 | Event News

 
Latest News

Electronic evidence of non-Fermi liquid behaviors in an iron-based superconductor

11.12.2018 | Physics and Astronomy

Topological material switched off and on for the first time

11.12.2018 | Materials Sciences

NIST's antenna evaluation method could help boost 5G network capacity and cut costs

11.12.2018 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>