Year/Course: 2008-2009, Easter 2009

Contact: Professor Stephen Elliott, Chemistry
Mentor: Dr. Julian White

The team of researchers led by Professor Elliott have been developing a system of MEMS-based sensors for measuring chemical compositions, including both sampling and callibration techniques.

The method uses commercially-available MEMS chips which contain an array of microcantilevers. The microcantilevers are coated with polymer-based receptor layers, and then bend up or down when other chemicals bind to the receptors. The deflection can be measured either statically or dynamically, and provides a means of measuring the concentration of the chemicals being targeted. This method has been shown to be highly sensitive, able to detect femtograms of material, and is also cheap, compact and robust. The microcantilevers can either be coated with the same receptor, or with different receptors, to increase the sensitivity and reliability of the sensor.

The research so far has successfully developed a new optical interferometry technique to measure the deflection of the microcantilevers, and also a new sample cell for detection of both liquid and gaseous samples. Much of the research has concentrated on counter-terrorism uses, such as detection of nerve agents, but the sensor also has much more general applicability, including a range of medical uses (for example PSA prostate antigens, blood sugar testing for diabetes, TB testing). It could also be used as an ‘electronic nose’ for complex products like wines and perfumes which are frequently counterfeited.

The next stage is to focus in on particular applications to allow the technology to be successfully commercialised. The challenge for the i-Team will be to identify high-value markets which can be addressed quickly by the technology and generate short-term revenues, as well as longer-term high-volume markets (such as home diagnosis kits) which will allow the technology to be widely used.