The application of an array of sensors based on boronic acid derivative for the quantitative analysis of amino acids

The objective of this work was to perform the quantitative analysis of 4 amino acids: phenylalanine (Phe), tyrosine (Tyr), ornithine (Ort) and glutamic acid (Glu) in mixtures with the use of potentiometric sensor array (electronic tongue) and Sequential Injection Analysis (SIA) measurement system. The flow-through sensor array was composed of 6 miniaturized classical ion-selective electrodes based on polymeric membranes (plasticized PVC) containing phenylboronic acid ionophore and/or an ion exchanger. The PLS analysis of the sensor array responses, measured in amino acids mixtures prepared by the SIA system (in two buffer solutions), permitted a correct quantitative analysis of only Glu and Ort. Further chemometric treatment, involving the extraction of dynamic components of the transient response employing the Fourier transform plus training of an Artificial Neural Network (ANN) with its coefficients led to the simultaneous determination of 3 amino acids, with a separate semiquantitative estimation of Tyr. (C) 2012 Elsevier Ltd....Selection and/or peer-review under responsibility of the Symposium Cracoviense Sp. z.o.o.