Navigation Links
Reveal the enemy
Date:7/20/2009

This release is available in German.

Bacterial diseases are usually detected by first enriching samples, then separating, identifying, and counting the bacteria. This type of procedure usually takes at least two days after arrival of the sample in the laboratory. Tests that work faster, in the field, and without complex sample preparation, whilst being precise and error-free, are thus high on the wish list. A Spanish research team headed by Jordi Riu and F. Xavier Rius at the University Rovira i Virgili in Tarragona has now developed a new technique to make this wish come true. With a novel biosensor, they have been able to detect extremely low concentrations of the typhus-inducing Salmonella typhi. As reported in the journal Angewandte Chemie, their new method is based on electrochemical measurements by means of carbon nanotubes equipped with aptamers as bacteria-specific binding sites. If bacteria bind to the aptamers, the researchers detect a change in electrical voltage.

Aptamers are synthetic, short DNA or RNA strands that can be designed and made to bind a specific target molecule. An aptamer that specifically binds to salmonella has recently been developed. The Spanish researchers chose to use this aptamer for their biosensor. By means of additional functional groups, they securely anchored the aptamers to carbon nanotubes, which were deposited onto an electrode in an ultrathin layer.

In the absence of salmonella, the aptamers fit closely against the walls of the carbon nanotubes. If the biosensor is put into a salmonella-containing sample, the microbes stick to the aptamers like flies to flypaper. This influences the interaction between the aptamers and the nanotubes, which makes a change in the electrode voltage noticeable within seconds.

Using this biosensor, the researchers were able to detect a bacterial concentration equivalent to one salmonella bacterium in 5 mL of medium. Quantitative measurements were possible down to a concentration of about 1000 salmonella per milliliter. This biosensor is specific: it does not react to bacteria other than Salmonella typhi. "Our new technique makes the detection of micro-organisms as fast and simple as the measurement of pH value," say Riu and Rius.


'/>"/>

Contact: Jordi Riu
jordi.riu@urv.cat
Wiley-Blackwell
Source:Eurekalert  

Related biology news :

1. Childhood obesity indicates greater risk of school absenteeism, Penn study reveals
2. Study begins to reveal clues to the cause and progression of sepsis
3. Comet probes reveal evidence of origin of life, scientists claim
4. Structure of 450 million year old protein reveals evolutions steps
5. UF scientists reveal how dietary restriction cleans cells
6. Neural stem cell study reveals mechanism that may play role in cancer
7. New method reveals substances on surfaces of any kind
8. Study reveals predation-evolution link
9. IDEMA Reveals Program Highlights for DISKCON USA 2007
10. Study reveals possible genetic risk for fetal alcohol disorders
11. IDEMA Reveals Program Highlights for DISKCON USA 2007
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Reveal the enemy
(Date:2/27/2017)... Feb. 27, 2017   Strategic Cyber Ventures , ... has led a $3.5 million investment in  Polarity , ... Cyber Ventures is DC based and is led by ... Thomas . Ron Gula , also a longtime ... participated in this series A round of funding. This ...
(Date:2/22/2017)... LONDON , Feb. 22, 2017 ... by 2021, ABI Research identifies four technologies that ... solutions to secure significant share in the changing ... payments, and passive authentication.   "Companies ... it comes to security," says Dimitrios Pavlakis ...
(Date:2/16/2017)... , Feb. 16, 2017  Genos, a ... announced that it has received Laboratory Accreditation from ... Accreditation is presented to laboratories that meet stringent ... demonstrate scientifically rigorous processes. "Genos is ... in laboratory practices. We,re honored to be receiving ...
Breaking Biology News(10 mins):
(Date:3/29/2017)... VA (PRWEB) , ... March 29, 2017 , ... ... wearable patch comprising multiple separable adhesive layers, as issued by the U.S. Patent ... layers as it applies to combining electronics and health monitoring. This invention will ...
(Date:3/29/2017)... OF PRUSSIA, Pa. , March 29, 2017 /PRNewswire/ ... to care, which is why CSL Behring awards Local ... work of rare disease patient groups. These groups tackle ... voices are heard on Capitol Hill and in statehouses ... funding cycle, the community-based grant was awarded to New ...
(Date:3/29/2017)... , March 29, 2017 QIAGEN N.V. (NASDAQ: ... announced the U.S. launch of its ipsogen ® JAK2 RGQ ... Food and Drug Administration as a qualitative in vitro diagnostic test for the ... blood.* ... is processed on QIAGEN,s Rotor-Gene ® Q MDx system, which is a ...
(Date:3/29/2017)... year,s petition to the White House signed by 120,000 ... generate awareness on the importance of new organic medicines and nutritional ... place. ... this month Health Advance (OTC PINK: HADV ), ... announced its endeavors on this generally recognized as safe ...
Breaking Biology Technology: