# Ionomer-Based Ion-Sensitive Field-Effect Transistor for Lithium Ion Sensing

## TL;DR

This paper presents a new ion-sensitive device that can detect lithium ions in solution, which is important for medical applications like monitoring bipolar disorder treatments.

## Contribution

The study introduces a simple, sensitive method for lithium ion detection using an ion-sensitive field-effect transistor with a Nafion membrane.

## Key findings

- The device achieved a sensitivity of 2.85 mA/decade for lithium ion detection.
- The detection limit was measured at 77 μM for lithium ions.
- COMSOL modeling confirmed the device's performance at 10–2 M lithium concentration.

## Abstract

Lithium detection
is critical in the medical field, as it is used
for the treatment of bipolar disorder. Here, we offer a simple method
using an ion-sensitive field-effect transistor device prepared to
detect the presence of lithium in a solution. The Nafion 115 membrane
used in this study has been conditioned to allow the transport of
lithium ions from the electrolyte to a zinc oxide-based transistor.
The device was studied with lithium ion concentrations ranging between
10–2–10–7 M. It was modeled
using the COMSOL Multiphysics program for 10–2 M.
The device showed 2.85 mA/decade sensitivity and a detection limit
of 77 μM.