Ministry of Defence (MoD) researchers have developed a low-cost handheld testing device that can simultaneously detect explosives and harmful biological and chemical substances.
The device, created at the MoD’s Defence Science and Technology Laboratory (Dstl), is designed to speed up and simplify testing for hazardous substances, including drugs, by soldiers and security personnel in the field.
The technology doesn’t need electricity and instead uses a hand-operated mechanism to collect and process samples. Pregnancy-test-style paper strips inside the device then indicate whether a specific chemical or biological substance is present.
‘Normally there would be a number of different steps and three or four components to separately manipulate the sample,’ said Dstl’s Dr Peter White, who worked with industrial design company Greaves Best Design to develop the device.
‘We needed to make the test easier to use in a stressful situation. The device also links a test result with a sealed sample that can be contained for further lab analysis.’
To operate the Integrated Multiplex Assay and Sampling System (IMASS), the user applies the small wet sponge at the end of the device to the suspect substance and then screws on a lid, which squeezes the liquid containing the sample into a test chamber.
This can be loaded with multiple test strips containing chemicals that produce a coloured line on the paper if a specific substance is present in the sample. This makes the device simple enough to be used without expert training.
‘The challenge was keeping it a simple, disposable device,’ said White. ‘We did this partly through material selection. For example, the sponge had to be good at picking up the sample but not so good it wouldn’t release it. We also had to find a way to integrate the sampling, the process of filtering and the delivery to the test strip.’
He added that the device was designed to cost less than £100 per unit and was probably closer to £50, although this would depend on the volume and could be cheaper if testing for a single substance.
It could eventually be used as a home-testing kit for viruses or sexually transmitted infections or to detect bacteria on surfaces in hospitals or the food industry.
The next phase of development will be to add a genetic testing component to the device, which would provide greater confidence in the results when testing for biological agents.
Dstl’s technology transfer company, Ploughshare Innovations, has licensed the technology to Cardiff-based diagnostics company BBI Detection, which is developing it for commercial production and plans to launch it next year.