Vertically Integrated People
Behind the Victorian sandstone façade of the James Watt Building at the University of Glasgow, technicians wearing white hoods,masks and lab coats are advancing the frontiers of science in one of the best-equipped cleanrooms in Europe. But although the ultra-modern Nanofabrication Centre may appear out of place in the old-fashioned campus, it continues a great scientific tradition which James Watt himself would be proud of…
From exploring the outer limits of physics to inventing a capsule which passes through the body to detect signs of cancer is a truly incredible voyage, but for Professor David Cumming it is not just the story of his own career so far but also a reflection of the way modern science is going.
Cumming is the head of the Electronics Design Centre (EDC) at the University of Glasgow, and was persuaded to return to his own alma mater by the opportunity to get involved in nano electronics, taking advantage of his academic background in physics and experience in industry with STMicroelectronics in Bristol.
One of the major attractions in Glasgow is the James Watt Nanofabrication Centre, with its worldclass facilities such as electron beam lithography and 750 square metres of cleanroom space, and the EDC’s sophisticated test and measurement equipment, including wafer probing up to 325 GHz. But for Cumming, the excitement comes from exploring new frontiers of science and electronic engineering, including bioelectronics.
“In other areas of electronics like defence and computing, we’re clear about where we are going,” says Cumming, “but biology creates new opportunities to do new things and open up new markets, and the margins are also much greater.”
Glasgow has been active in the field of bioelectronics for several decades, and the EDC has moved on from developing simple devices to systems, including sensors on a chip – for applications ranging from security to medicine.
One of the EDC’s most promising inventions is the LabInAPill, a miniature device developed by Cumming and his colleague Professor Jon Cooper which addresses the need for preventionoriented devices in healthcare, now being taken to market by a spinout company called Wireless Biodevices.
According to Cumming, the LabInAPill has the potential to greatly reduce deaths from one of the biggest killers today – bowel cancer. Worldwide, there are one million new cases a year and 500,000 deaths, but if diagnosed early, survival rates can be as high as 90 per cent, so any improvement on current technology would be welcome, to replace colonoscopy, which is intrusive, expensive and time consuming, and faecal blood tests – which are not just unpleasant but also produce false positives half of the time.
LabInAPill is a “use once and throw away” wireless device which measures just 2.5cm in length. It is the end result of almost 60 years of research that began with the invention of the transistor. In the early days, the notquitesotiny devices were inserted still attached to a wire, but advances in wireless and video technology, combined with micro sensors and the “systemonachip,” have enabled researchers at Glasgow University to make dramatic advances, not just in miniaturisation but also in sensor capabilities, including the detection and measurement of acidity, dissolved oxygen, glucose/fatty acids blood and tumour markers, as well as temperature and pressure – plus a camera.
A primary achievement of Cumming’s group is to integrate different components on a single IC containing the microcontroller, plus sensors, memory, data encoder and wireless transmitter, just 5mm across. In addition to reducing the size of smart diagnostic devices, and improving the sensitivity of sensors, the major challenges are battery power and wireless transmission. For example, due to the density of organs like the liver, the location of the “pill” in the body has different effects on transmission of radio signals, so Cumming’s group created a three dimensional model of the human body, “slicing and dicing” it into 4.5 million cubes to measure the signal from every location – ultimately to improve reception and therefore the accuracy of diagnosis.
According to Cumming, the developers are confident that as the underlying technologies come down in price, the sky is the limit for sales – potentially hundreds of thousands of pieces a year. The other challenges for this and other similar devices, says Cumming, are to make better use of the “dead space” on the chip and “eliminate interconnect”, to make the chips smaller, at the same time as lowering power consumption and improving the sensors themselves.
The EDC has also developed the world’s first single chip pH meter, while another market with enormous potential is “patch clamping” –a technique for studying ion channels in cells, traditionally done with a glass micropipette, where biosensors promise huge advantages. Other breakthroughs include CMOS chips for monitoring the growth of cells, and proton cameras. As well as diagnosis, these and other similar devices will be used in pharmaceutical research – for example, testing new drugs in a “lab on a chip”, tissue engineering and cell screening.
One of the major issues in development is how to eliminate “biocidal” materials such as aluminium oxide that kill tissues in contact with the sensors. This is achieved by using a “biocompatible” method called electroless gold plating. Another problem is surface topography – developers discovered that the cells they were trying to monitor would not grow on certain types of surfaces because they are not “biofriendly.”
To solve such problems, Cumming and the EDC work very closely with other departments, and it is this collaboration which he believes makes the big difference in Glasgow, with chemists, physicists and biologists sharing the facilities, in the search for mutual progress.
In Cumming’s view, the EDC has strengths in several areas like ultrafast transistor technologies, bioelectronics and biosensors, nanofabrication, microwave test and measurement facilities, sensors/system on a chip, and optoelectronics for the telecoms industry. It has also been a pioneer for several decades in several technologies like biosensors, but above all, says Cumming, the key to success has been cooperation and what he describes as the “vertical integration” of facilities and people from various branches of science, working side by side with electronics engineers. He himself is primarily an electronics engineer who trained in a physics laboratory, and his department has recruited staff and students including several chemists and biologists, to create a multidisciplinary atmosphere and promote cooperation.
What makes the EDC different, says Cumming, is also its ability to do fundamental research at the same time as actually making its own prototypes and testing them right on the spot.
“The EDC is where micro meets milli and nano meets micro”, says Cumming, “and there’s plenty of room in the middle.”