EIS-Capacitor-Based LC Wireless Chemical Sensors

The development of new wireless sensors for the measurement of different chemical parameters is reported. A high quality factor EIS (Electrolyte-Insulator-Silicon) capacitor is used as an electrochemical potential-to-capacitance transductor to obtain a LC wireless pH sensor. Measurement of conductivity with the same sensor has been also achieved by exciting it at a different frequency. Detection of other ions than [H+] by deposition of ion selective membranes is demonstrated as well.