Impedance Study of Drinking Water and Tastants using Conducting Polymer and Metal Electrodes
Mopsy Dhiman1, Pawan Kapur2, Abhijit Ganguli3, Madan Lal Singla4

1Mopsy Dhiman, Central Scientific Instruments Organization, CSIR, Chandigarh 160020, INDIA.
2Pawan Kapur, Central Scientific Instruments Organization, CSIR, Chandigarh 160020, INDIA.
3Abhijit Ganguli, Central Scientific Instruments Organization, CSIR, Chandigarh 160020, INDIA.
4Madan Lal Singla, Central Scientific Instruments Organization, CSIR, Chandigarh 160020, INDIA.

Manuscript received on April 11, 2012. | Revised Manuscript received on April 14, 2012. | Manuscript published on May 05, 2012. | PP: 1-6 | Volume-2 Issue-2, May 2012 . | Retrieval Number: A0487032212/2012©BEIESP
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© The Authors. Published By: Blue Eyes Intelligence Engineering and Sciences Publication (BEIESP). This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Abstract: In this study the sensing capabilities of a combination of metals and conducting polymer electrodes for drinking water and dissolved tastants using an AC-impedance mode in frequency range 102 to 105 Hz at 0.1 V potential has been carried out. Classification of seven different bottled and municipal drinking water samples along with various tastants dissolved in DI water (DI water) for KCl (5mM) (salty), HCl (5 mM) (sour) quinine (0.1 mM) (bitter), sucrose (5 mM) (sweet), black tea liquor, black tea liquor with sucrose (2% sugar solution), and a bottle of “packed” orange juice has been made using six different working electrodes in a multi electrode setup using PCA. Working electrodes of Platinum (Pt), Gold (Au), Silver (Ag), Glassy Carbon (GC) and conducting polymer electrodes of Polyaniline (PANI) and Polypyrrole (PPY) grown on an ITO surface potentiostatically have been deployed in a three electrode set up. The impedance response of these water samples using number of working electrodes shows a decrease in the real and imaginary impedance values presented on nyquist plots depending upon the nature of the electrode and amount of dissolved salts present in water/tastants. The different sensing surfaces allowed a high cross-selectivity in response to the same analyte. From PCA plots it was possible to classify drinking water in 3-4 classes using conducting polymer electrodes; however tastants were well separated from the PCA plots employing the impedance data of both conducting polymer and metal electrodes.

Keywords: Sensing electrodes, AC-impedance, Principal component analysis, Drinking water, tastants, conducting polymers.