Highly sensitive and reusable ion-sensor based on functionalized graphene
Ana Paula Pereira Alves, Leonel M. Meireles, Gustavo Ferrari, Thiago Henrique Rodrigues da Cunha, Mariana Ogando Paraense, Leonardo C. Campos, Rodrigo G. Lacerda
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.