Rapid, one-step, ultra-sensitive detection of food poisoning bacteria and biothreats

April 16, 2007

A new mosquito-sized biosensor can detect amazingly small amounts of disease-causing E. coli bacteria in food in a single-step process that takes only minutes, compared to hours required with conventional tests for that common food poisoning agent, researchers in Philadelphia are reporting.

The sensor also can quickly detect proteins important in medical diagnostic testing and very low levels of biothreats such as anthrax, according to the study, published in the current (April 1) edition of ACS’ Analytical Chemistry.

In the study, Raj Mutharasan and colleagues point out that rapid measurements of very low concentrations of pathogens and proteins could have wide application in medical diagnostic testing, monitoring for biothreat agents, detecting contaminated food products and other areas. Existing tests for low-level pathogens, however, take time because they require a step to boost the concentration of microbes in a sample. No direct test currently exists for low-levels of proteins, the report adds.

The study describes use of the biosensor to detect E. coli in ground beef and other materials at some of the lowest concentrations ever reported. At the heart of the new biosensor is a vibrating cantilever, with a tiny beam supported at one end and coated with antibodies at its other, free-moving end. The antibodies are specific to the material being detected, such as E. coli, anthrax or proteins that are biomarkers for disease. When that antigen is present in a sample flowing through the biosensor, it binds to the cantilever and alters the frequency of vibration in a way that can be detected electronically.

Source: ACS

Explore further: New graphene oxide biosensors may accelerate research of HIV and cancer drugs

Related Stories

Diatom biosensor could shine light on future nanomaterials

March 23, 2012

(PhysOrg.com) -- A glow coming from the glassy shell of microscopic marine algae called diatoms could someday help us detect chemicals and other substances in water samples. And the fact that this diatom can glow in response ...

Future biosensors could be woven into clothes

June 23, 2015

Commonly used health tests, such as pregnancy and blood sugar tests, involve putting a drop of fluid on a test strip, which is infused with a substance designed to detect a specific molecule.

Recommended for you

The dark side of Nobel prizewinning research

October 4, 2015

Think of the Nobel prizes and you think of groundbreaking research bettering mankind, but the awards have also honoured some quite unhumanitarian inventions such as chemical weapons, DDT and lobotomies.

Internet giants race to faster mobile news apps

October 4, 2015

US tech giants are turning to the news in their competition for mobile users, developing new, faster ways to deliver content, but the benefits for struggling media outlets remain unclear.

Trade in invasive plants is blossoming

October 3, 2015

Every day, hundreds of different plant species—many of them listed as invasive—are traded online worldwide on auction platforms. This exacerbates the problem of uncontrollable biological invasions.

Fusion reactors 'economically viable' say experts

October 2, 2015

Fusion reactors could become an economically viable means of generating electricity within a few decades, and policy makers should start planning to build them as a replacement for conventional nuclear power stations, according ...


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.