Electrical Impedance Spectroscopy-Based Detection and Quantification of Methanol Vapors by Use of Phospholipid Langmuir-Blodgett Film

Methanol gas-sensitive element was designed from 3-nm phospholipid Langmuir-Blodgett (LB) film deposited on interdigitated gold microelectrodes. The LB molecular monolayer was prepared from phospholipid dipalmitoyl-phosphatidyl-ethanolamine (DPPE). In view of gas detection applications, we have studied the electrical impedance of DPPE LB sensor when it was exposed on vapors of methanol at ambient temperature. The response of the DPPE LB sensing film to methanol vapors was tested by complex electrical impedance spectroscopy in the frequency range 0.1 Hz -100 KHz of the applied electric field.