Scientists in the UK have developed an interesting use for cosmetics. Craig Banks and co-workers from Manchester Metropolitan University used an off-the-shelf antiperspirant product to make a random microelectrode array sensor. 

Electrochemical sensors based on random microelectrode arrays have significant benefits such as very low detection limits and fast responses. They are currently being evaluated in areas ranging from biosensors and medical diagnostics to food and beverage analysis. However, reproducibility and cost limit their transfer from the laboratory to the field explains Banks. 

'There are many ways to produce a random microelectrode array but they are either technologically challenging or time consuming', he says. 'For these devices to be widely accepted, we need new methods of fabrication. Our method is promising as it has the required reproducibility yet is extremely cost- effective'. 

The group show that spraying a cheap graphite screen printed electrode with antiperspirant transforms it into a random microelectrode array in seconds. The polymer in the antiperspirant coats the electrode surface, leaving micrometre-sized holes showing underlying electrodes, which are accessible to the solution being analysed. 

Jose Pingarron, an expert in electrochemical sensors and biosensors at the Complutense University of Madrid, Spain, describes the work as curious. 'The strength is the obvious ease of the ensemble preparation and the very low cost of it,' he says, but adds that more work is required to optimise the analytical performance. 

Banks used the microelectrode array to detect trace amounts of lead in a solution. Now he hopes to be able to apply this simple method to produce other types of microelectrode array to measure important analytical targets. This method could be a cost-effectivefuture manufacturing route for these devices, but development will be needed to scale up the process, says Banks. 

Fay Nolan-Neylan 

Enjoy this story? Spread the word using the 'tools' menu on the left or add a comment to the Chemistry World blog.