Efficient taste sensors made of bare metal electrodes

Abstract

In attempts to reduce cost and increase sensitivity of taste sensors we have found out that a novel, inexpensive set of chrome-deposited electrodes may be used in impedance spectroscopy measurements for sensing with great performance. High sensitivity is demonstrated by detecting, reproducibly, μM amounts of NaCl, HCl, sucrose, which represent basic tastes, and Cu2+ ions. This high sensitivity can also be used to distinguish complex liquids such as wines. Surprisingly, there was no need to cover the metal electrodes with nanostructured films of organic sensitive materials, which further reduces the cost of the sensing units. This sensitivity is attributed to interface effects between the metal electrodes and the liquid samples, which may be investigated with atomic force spectroscopy as illustrated in this paper. Copyright © 2006 American Scientific Publishers.