Nano self-assembled ion-sensitive field-effect transistors for acetylcholine biosensing

Abstract

In this paper, the fabrication and characterization of acetylcholine biosensors based on nano self-assembled ion-sensitive field-effect transistors (ISFETs) are demonstrated. The fabrication is implemented with a very low-cost layer-by-layer nano self-assembly technique. A self-assembled polyaniline thin film works as the semiconducting channel material, while a SiO2 nanoparticle thin film serves as the gate dielectric material. A typical polyaniline ISFET operates at a low-voltage range and has a mobility of 1.49 cm2/Vs. Acetylcholine in a concentration as low as 1 µM could be detected with this sensor. The results presented herein suggest a route to inexpensive ion-sensitive field-effect transistors for biosensing applications.