`Green Chemistry'
21 January 2005

Dr Nick Gathergood

Dr Nick Gathergood of the School of Chemical Sciences is currently collaborating in a research project into ionic liquids with improved biodegradation. This work illustrates a commitment by the School of Chemical Sciences at DCU to develop clean and environmentally friendly chemical processes which have potential industrial applications. Dr Gathergood's research partners are Dr M Teresa Garcia, Department of Surfactant Technology, IIQAB-CSIC, Spain and Professor Peter Scammells, Department of Medicinal Chemistry, Monash University, Australia and Glaxo Wellcome Australia.

It is expected that the research will have implications for the environment, since ionic liquids are used as solvents in a wide range of synthetic and analytical processes. Given the current pressure to reduce incineration and landfill waste, the need for industrial solvents that can biodegrade is continually increasing. Another advantage of ionic liquids is their negligible vapour pressure. This reduces the exposure of workers to toxic solvent fumes, which leads to a healthier working environment.

The surfactant industry has invested a great deal of resources into improving the properties of detergents, in particular by developing biodegradable washing powders. Lessons learned from this research were directly applicable to Dr Gathergood's work, allowing significant improvements to be made to these novel solvents.

As part of the research, acute toxicity tests on freshwater crustacean such as the Daphnia magna (see accompanying photo) as well as on saltwater bacteria (Photobacterium phosphoreum) were carried out to assess the aquatic toxicity of commercially available ionic liquids. The results show a trend between ionic liquid structure and toxicity and work is in progress to develop new ionic liquids with improved toxicity profiles. The ideology of the project was to keep everything simple. Short and robust syntheses of ionic liquids in high yields are important, as cost is a major factor. A series of ionic liquids was also prepared to study the effect of the anion on biodegradation and toxicity.

Dr Gathergood's research featured as the inaugural cover illustration of January's `Green Chemistry', a publication of the Royal Society of Chemistry.