A method of pulse array design for voltammetric electronic tongues

This paper proposes a reasonable methodology for the design of pulse arrays applied in classification and quantification techniques based on the use of pulse voltammetric electronic tongues. As model problem we designed a procedure to predict levels of ferrocene, TCNQ and Ru(bipy)32+ using a voltammetric electronic tongue employing a set of noble electrodes; i.e. Au, Pt, Ir and Rh. Ferrocene, TCNQ and Ru(bipy)32+ have been selected as model compounds because these are molecules with well defined redox processes. The electrodes were housed inside a stainless steel cylinder which was used as the body of the electronic tongue system. A SCE was used as reference electrode. An electrochemical study of the response of ferrocene, TCNQ and Ru(bipy)32+ was carried out as a first step with the aim of characterise the redox processes in these compounds. Different samples containing ferrocene, TCNQ and Ru(bipy)32+ were prepared following an experimental design in which a system of three compounds/three levels was established. Multivariate analysis based on Partial Least Square (PLS) techniques was applied for data management and prediction models building. Several set of pulses were tested and a general procedure to their design for their use in voltammetric electronic tongues is discussed and proposed.