Vantix Biosensor offers portable antibiotics test potential

Fera study with Universal Sensors technology shows results in under one hour

Fast, simple testing for antibiotics in animal feeds may soon be possible on the farm. Results from a Defra funded research project (VMO2154) conducted by the Food and Environment Research Agency (Fera) have demonstrated that technology developed by Universal Sensors offers high sensitivity while using low-cost equipment, making it an extremely attractive alternative to conventional laboratory-based antibiotic detection. A rapid test at the point-of-use would allow a more effective response to a positive (non-compliant) sample to be actioned.

Adding antibiotics to animal feed boosts growth rates and has been industry practice for decades. However, widespread use of antibiotics can lead to resistant strains of bacteria emerging, and the possibility that resistance will be passed to bacteria that infect humans. The EU is determined to tackle this problem, so have banned the use of antibiotics as feed additives.

The ban is upheld by routine testing, but current methods are slow and expensive. The results, presented by Dr Sara Stead and her team from Fera at the Sixth International Symposium on Hormone and Veterinary Drug Residue Analysis, Ghent 1-4 June 2010, demonstrated that the Vantix^TM biosensor has the potential to detect a wide range of antimicrobial growth promoters in animal feed and generate the results in less than an hour. The bioassay developed can be used as both a rapid laboratory-based procedure or as a portable field test for simultaneous measurement of up to 12 samples.

Dr. Duncan Purvis of Universal Sensors said that the results were important as it demonstrated how existing assays can be moved out of the lab and into the field, creating the potential for rapid screening.

A portable test would prove invaluable in the fight against the development of resistant bacteria. Rapid testing on site opens up possibilities such as a reactive response, whereby a positive result would trigger wider testing on that farm.

The Vantix technology also improves the sensitivity of existing assays and requires less preparation of the samples prior to testing and this can be invaluable in the real world where the analyst may be working in a shed.

A key quality of the Vantix biosensor is its simplicity. The Vantix uses electrodes which produce an electronic signal when samples contain the banned substance, this generates a Yes/No response on a portable computer, making it extremely easy to use.

The Vantix biosensor has already shown potential to revolutionise the detection of hospital superbugs. Now Feras studies have demonstrated that the technique can be used to detect multiple banned antibiotics, and suggested there could be wider applications for farming. The detection methods used on animal feeds could also be applied to samples such as meat and honey. These tests for antibiotics higher up the food chain reduce the likelihood of antibiotics appearing in products on the supermarket shelves.

The tests carried out by Fera demonstrate the sensitivity and accuracy that can be achieved by the Vantix biosensor. There was very close agreement between results produced by the Vantix biosensor and those gained from standard laboratory procedures.

The Vantix biosensor employs single use screen-printed electrodes. The use of disposable electrodes overcomes one of the limitations of previous electrochemical biosensors, which suffered from electrode fouling by previous samples. The procedure requires basic equipment and non-toxic solvents.

Existing ELISA assays can easily be migrated on to the Vantix platform offering the potential to make a laboratory-based test available on a portable device.