Swarms Of Space Bugs For Blood Testing – And More

Equipped with a power supply, limited intelligence and monitoring systems, the bugs would be small enough to send en masse to hard-to-reach places, like pipes carrying liquids on space stations.

There, monitoring changes in temperature or flow could warn of impending malfunctions.

To move the bugs, the scientist hit on using cilia-like motion, much like some deep-sea creatures use to propel themselves. They covered one face of the microchip with tiny cantilever arms.

“They would then move along on these like millipedes,” said Dr Djakov, now Director of Sensor Development at Microvisk Technologies.

In the end, the space bugs were ahead of their time: they haven’t yet progressed past the testing phase.

But the cilia approach – the cantilever arms to propel the bugs – has gone further.

Cantilever: A close-up image made with a scanning electron microscope of Microvisk’s cilia-like micro-cantilevers. Each cantilever is Π-shaped and 600µ long. The cantilevers are based on Micro Electro Mechanical System (MEMS) technology that propels prototype space bugs through liquids.
The prototypes were designed and developed to monitor hard-to-reach pipes in space stations but the technology is now being used to monitor patients with blood coagulation problems.

Credits: V. Djakov

 
Space cantilevers spin off

STFC Innovation, ESA’s Technology Transfer Programme partner that operates the agency’s Business Incubation Centre Harwell in the UK, saw the business potential in the medical market and supported start-up company Microvisk to spin off the technology.

At Microvisk, Dr Djakov’s team stripped down the microchips and put the intelligent sensing mechanisms right into the cantilever arms, almost like a cat’s whiskers.

Microvisk’s Micro Electro Mechanical System (MEMS) chip with flexible cantilevers and integrated sensing and actuator modules. The microchip was originally conceived for prototypes designed to monitor hard-to-reach pipes in space stations.

Credits: Semefab Ltd

These whiskers turned out to be very good at monitoring liquids. Sweeping through, they note changes in viscosity and register if anything is suspended in the liquid.

“This is very interesting for probing blood, plasma, and other bodily fluids,” said Dr Djakov.

At present, investors are betting on a device to monitor blood coagulation for patients taking blood thinner medication: “It’s like a diabetes test, but for thrombosis.”

Thanks to this coagulometer, the Microvisk CoagLite, patients will soon be able to test themselves at home with the prick of a finger.

Microvisk’s hand-held CoagLite instrument with a disposable test strip used to test patient’s blood. “It’s like a diabetes test, but for thrombosis” says Dr Vladislav Djakov, the instrument’s inventor. Thanks to Microvisk’s CoagLite coagulometer, patients will be able to test themselves at home with the prick of a finger.

Credits: Microvisk Ltd

 
After a small chamber inside the test strip fills with blood, the tiny cantilever sweeps the drop, monitoring how quickly it coagulates.

“You need less blood, which means there is less pain,” said Dr Djakov, who compared its ease-of-use to diabetics’ simple glucose monitors. “Haematologists are finding it really important.”

Now undergoing clinical testing with US Food and Drug Administration, the coagulometer should be on the market later next year.

Microvisk’s hand-held CoagMax instrument designed for doctors and hospital staff to measure patients’ blood coagulation . It is based on the same technology as the consumer-model CoagLite but the results can be sent to a central computer database for easy comparison with previous readings.

Credits: Microvisk Ltd
 
But the whisker technology isn’t limited to testing blood.

“It would be good for things like plasma or teardrops,” said Dr Djakov, “or to test the oil in a car engine, or in the food industry, to test chocolate or ketchup.

“There are literally hundreds of applications, for this innovation which started as a ‘space bug’.”