Project A: Development of small, rapid metal sensors for in situ applications in both biology and the environment.

Metal ions play pivotal roles in both the environment and biology. Heavy metal ions are becoming an increasing environmental problem and have affected both terrestrial and aquatic biota. Major sources of these heavy metals include cosmetics, fertilizers, and industrial/household waste. These heavy metal ions do not biodegrade and many (i.e. Pb, Cd, Hg, Cr, and As) are toxic at even small doses. The World Health Organization has marked heavy metals as priority substances that need to be monitored and have set certain permissible concentration limits in water sources.

Further, the understanding of these metal ions in biology is still in nascent stages. For example, it is unclear what the role of Cu(II) is in the formation of amyloid plaques, the hallmark of neurodegenerative diseases such as Alzheimer’s.

While there are powerful methods for quantifying these concentrations, they are not portable and often require sample preparation and analyses be performed off-site, preventing real-time monitoring of changes in the environment. Clearly there is a need for rapid sensing technologies for in situ measurements.

We propose carbon fibre microelectrodes with chemically altered surface chemistry selective to our heavy metal of interest enabling detection via voltammetric techniques. This will allow us to build small, portable and selective heavy metal biosensors to be used in situ in an environmental and biological context.