Abstract
This work describes our recent progress and achievements in the field of fully automated biosensors (Automated Water Analyser Computer Supported System (AWACSS) and River Analyser (RIANA)) for unattended, cost-effective and continuous monitoring of environmental pollution. We report on ultra-sensitive immunoassays for the hormones progesterone, testosterone and estrone and the pesticides propanil and isoproturon as examples of the outstanding progress made on biosensors in the field of environmental monitoring and water analysis. Most of the bio-active organic pollutants (estrone, progesterone, propanil and isoproturon) were detected at levels as low as 1.0 pg mL−1 or even below. In fact, the reported limits of detection (LOD) were between 0.2 and 6.0 pg mL−1. For the first time, commercially available derivatives and antibodies were incorporated into immunoassays (progesterone and testosterone) for fully automated biosensors. To verify the assay performance for quantifying testosterone, progesterone, and isoproturon in real-world samples using our immunosensors, we spiked river and drinking water at six different levels from 0.9 pg mL−1 to 90 ng mL−1. Nearly all recovery rates could be obtained between 70 and 120% as the AOAC International recommends it chiefly for water analysis.
Acknowledgements
This work was funded by the ‘Automated Water Analyser Computer Supported System’ (AWACSS) (EVK1-CT-2000-00045) research project supported by the European Commission under the Fifth Framework Programme and contributing to the implementation of the Key Action ‘Sustainable Management and Quality of Water’ within the Energy, Environment and Sustainable Development. The development of the former biosensor used was funded by the European Commission under the Environment and Climate Program (Fourth Framework Programme) River Analyser (RIANA) (ENV4-CT95-0066) project. The monoclonal antibody anti-isoproturon was a gift for research from Petra Kraemer, GSF–National Research Centre for Environment and Health, Institute for Ecological Chemistry, Neuherberg, Germany. All other non-commercial antibodies and derivatives were kindly supplied by Ram Abuknesha, King's College London, London, UK. Jens Tschmelak is a scholarship holder and Guenther Proll is participant of the research training group ‘Quantitative Analysis and Characterization of Pharmaceutically and Biochemically relevant Substances’ funded by the Deutsche Forschungsgemeinschaft (DFG) at the Eberhard-Karls-University of Tuebingen, Tuebingen, Germany.