Development of specific electrodes of an electronic tongue for detection of important chemical compounds present in tea

Abstract

The task of discrimination by an E-tongue is rapid and can be easily tunable, but the sensing materials used here normally consist of noble metals which have low selectivity and are also not specific to the target analyte. Moreover, the data obtained from an E-tongue generally contains a pattern of waveforms that is processed by means of appropriate recognition algorithms. In regard to the above limitations, it is believed that the performance of an E-tongue could be enhanced if functionalized electrodes are used instead of noble metal electrodes. Therefore, to overcome certain limitations of an E-tongue, i.e., to decrease the number of individual sensors and enhance the sensitivity of them simultaneously, molecularly imprinted polymer (MIP) based technique have been proposed in this thesis work. The present thesis titled “Development of specific electrodes of an electronic tongue for detection of important chemical compounds present in tea” explores the possibility of the development of the electrodes, each specific for an individual taste attributing agent of tea. Here three different electrodes have been synthesized using the principle of MIP for the selective detection of total theaflavins (TF), catechin (+C), and epigallocatechin-3-gallate (EGCG), respectively. The particle size, structural variations and the morphological changes of the imprinted electrodes were characterized using powder X-ray diffraction (PXRD) technique, fourier transform infra-red (FTIR) spectroscope and field emission scanning electron microscope (FESEM), respectively. The analytical characteristics of all the electrodes have been detailed in this work. Furthermore, in order to have an insight to the performance of the electrodes towards quantification of the different analytes in tea samples for real time applications, partial least square regression models have been executed and its different parameters have been calculated.