Handheld device detects illegal drugs and super bugs

A new method of detecting illegal drugs and super bugs will be used in a government-backed handheld device that analyses saliva.

The Vantix portable reader will be able to test for chemical substances or bacteria such as MRSA in human or animal saliva within minutes, for as little as £1.50 per test.

It works by measuring the electric charge generated when the substances in the saliva react with an electrode coated with antibodies.

The firm behind the device, Cambridge-based Universal Sensors, said its method is more sensitive and effective than existing saliva tests because it produces a digital signal instead of an analogue one.

Rather than using a chemical reaction to produce a colour that confirms the presence of a substance, the Vantix device assesses the resulting charge and uses software to convert this into a measurement of how much substance is present.

‘This method is surprisingly resistant in the worst samples,’ Universal’s commercial director Kevin Auton told The Engineer. ‘Things like faeces, urine and saliva are dreadful samples to work with; even in ground up animal feed where we’re detecting illegal use of antibiotics.’

Up to 10 substances could be tested for at once through the use of multiple electrodes on a plastic disposable test cartridge. The saliva sample is collected by giving the patient or suspect a chewable swab that is then placed in the cartridge and inserted into the reader.

Universal intends the reader to cost £350 and the tests between £1.50 to £10 depending on its use. ‘We’re trying to make it very inexpensive and deskilled so that you’re moving the tests from a laboratory out into the field so it can be used by non-scientists,’ said Auton.

A prototype model is being distributed to early adopters and Universal plans to release the technology through a series of different platforms for different situations over the next two years.

‘There may be a need for one person to do one test so the platform is disposable,’ said Auton. ‘There may be another situation where someone is having to test 100 animals on a farm to see if they’ve been fed illegal antibiotics and so you have a slightly more automated platform.’

Universal funded the development of the reader with £100,000 awarded by the National Institute for Health Research (NIHR) under the Small Business Research Initiative (SBRI). The company is set to receive a further £750,000 to take the Vantix to market under the second phase of the programme.