Using cyclodextrins to clean up the water supply
Exposure to heavy metals such as mercury and lead can cause severe health problems in humans. Despite attempts to limit emissions of these environmental pollutants, heavy metals still find their way into our drinking water. The CYCLODEXWATERPUR project aimed to develop new, non-toxic compounds that efficiently remove these heavy metals from the water supply. The project was funded in part by INCO 2 and involved leading chemists and research labs from Russia and the Ukraine as well as the EU. Led by the University of Surrey, the group worked with cyclodextrins, a family of polymeric compounds with a number of key properties. In particular, cyclodextrins can attract hydrophobic molecules while remaining soluble in water. The material properties of different cyclodextrins, chiefly their attraction for heavy metal ions, were analysed using techniques such as UV/Visible spectrophotometry, macro and microcalorimetry and differential thermal analysis. The cyclodextrins exhibiting favourable profiles were then embedded into carriers such as polymeric matrices or silica. A final set of tests determined which combinations could absorb the highest amounts of heavy metals when introduced to polluted water samples. These polymeric materials are relevant for water purification in Europe and could have an even greater impact on water quality in developing countries. Other applications in the field of biomedicine also beckon. Dissemination of the findings is taking place at conferences and through publications in peer-reviewed journals.