Optical Biosensor for the Determination of Trace Pollutants in the Environment

A robust, cost-effective, automated, and immunoassay-based water analysis system is used to determine several organic pollutants at low concentration levels (a few nanograms per liter) without requiring any time-consuming sample preconcentration or pretreatment. This system uses total internal reflection fluorescence (TIRF) as the transduction method employing bulk as well as integrated optical waveguides to allow low limits of detection and quantification. More than 20 analytes have been determined. The system allows remote operation and automated data processing; evaluation strategies and the results of field tests are discussed. Pollutant values exceeding predefined threshold values cause an alarm signal via telemetry. Keywords: TIRF (total internal reflection fluorescence); water analysis; pesticides; endocrine disruptors; field tests