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 Alkaline soil, sensible sensor
03.08.2017 | American Society of Agronomy

nachricht New 3-D model predicts best planting practices for farmers
26.06.2017 | Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign

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: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>