Highly sensitive and reusable ion-sensor based on functionalized graphene

Abstract

Some sub-products from the industrial activity are rich in metals, very often being highly toxic to human health and to the environment. Thus, the development of real-time and ultrasensitive techniques for metals detection is relevant. Herein, we report an ion-sensitive field-effect transistor (ISFET) based on l-phenylalanine functionalized graphene that detects Na+, Co2+, and Al3+ at the nanomolar range and Cu2+ at the picomolar range. Our sensor is prepared using a simple functionalization method and is reusable after a standard HCl cleaning process. Altogether, the ISFET is a promising device for real-time detection of metal ions at low concentrations.