Nano Self-Assembled Nanoparticle Ion-Sensitive Field-Effect Transistors for Acetylcholine Biosensing

We present an inexpensive way to fabricate high-performance nanoparticle based ion-sensitive field-effect transistors (ISFETs) for the acetylcholine biosensing application. The fabrication is implemented with a low-cost layer-by-layer nano self-assembly and microfabrication techniques. Self-assembled silica nanoparticle thin film and indium oxide nanoparticle thin film work as the gate dielectric and semiconducting channel respectively. The ISFETs operate at a low-voltage range of less than 2 V, and has a high mobility of 43.10 cm²/Vs. Acetylcholine in a concentration as low as 100 nM could be detected with this sensor. The results presented herein suggest a route to inexpensive, high mobility ion-sensitive field-effect transistors for biosensing applications.