Chemically diverse modified electrodes: A new approach to the design and implementation of sensor arrays

An array of five gold electrodes modified with different substituted alkane thiols has been developed that is sensitive to the identity of a series of similar redox active analytes. A double-potential-step methodology was used to interrogate the electrodes in order to extract a maximum amount of info rmation on a short time-scale. The resulting response patterns, containing 80 variables, were used in conjunction with principal component analysis an d artificial neural networks for pattern recognition. The degree of overlap ping sensitivity between 80 variables as well as reproducibility from measu rement to measurement and array to array is discussed. Finally, a method fo r normalizing the response patterns in order to produce concentration indep endent patterns is described. (C) 1999 Elsevier Science B.V. All rights res erved.