Sensitive cyclodextrin–polysiloxane gel membrane on EIS structure and ISFET for heavy metal ion detection

Cylodextrin (CD)–polysiloxane gel matrices are used to functionalize EIS (Electrolyte Insulator Semiconductor structure) and ISFET (Ion-Sensitive Field Transistor) devices. Electrochemical measurements were made to study the sensitivity and the selectivity of this sensitive membrane towards heavy metal ions. For both structures, a Nernstian response and good detection limit of an αCD gel membrane towards Cd2+ ion and for a βCD towards Pb2+ ion were obtained. The selectivity with respect to other cations are given through the potentiometric selectivity coefficients (Kij).