BIOSENSORS FOR THE DETECTION OF HEAVY METAL IONS

Abstract

A concept for the development of biosensors for the detection of heavy metal ions in aquaeous solution is introduced. Phytochelatins, metallothioneins and glutathione are used as biological components for the heavy metal sensors. These peptides/proteins selectively bind heavy metal ions via thiolate complex formation. The biological component is immobilized at the surface of an appropriate transducer. Changes within the layer of immobilized peptides/proteins, effected by binding of metal ions (e.g. release of protons, changes of mass and optical properties), are transformed into electrical signals by the transducer (proton-sensitive field effect transistor, resonating piezoelectric crystal or optical device). Preliminary experiments demonstrate the suitability of phytochelatins and glutathione as biological components for the development of biosensors for heavy metals.