Electronic tongues: Electrode arrays and pattern recognition

the current response of an array of different metal electrodes subjected to a train of voltage pulses can be used to classify and quantify liquid samples. the electrode array, together with proper signal evaluation and a pattern recognition method is called a voltammetric "electronic tongue". the principles of voltammetric evaluation of electrode arrays are discussed as well as the parameters in the liquid that are monitored by the method. examples of applications of voltammetric electronic tongues are given to demonstrate their use in (industrial) processes. the examples include monitoring of water quality and an exploratory biomedical use of a miniaturized electrode. finally some possible future developments will be speculated upon.