Abstract
Periodic detection of alcohol using an enzymatic electrochemical sensor is often inadequate for prolonged monitoring. Herein, a low-cost, portable screen-printed (SPE) flexible electrode-based sensor is constructed for long-term monitoring of ethanol. The sensor relies on a sensory layer composed of copper oxide nanoparticles (CuO NPs) embedded within the conductive polyaniline (PANI) network immobilized with alcohol oxidase (AOX). The CuO-PANI/AOX/SPE produced a robust response for the enzymatically produced H2O2 (from EtOH) at a relatively lower potential (+ 0.34 V) and could distinguish and detect EtOH in PBS buffer and artificial sweat samples using a 10 mu L sample volume and a current response lasting over 180 s. The sensor exhibited excellent working linearity for EtOH detection in the concentration range of 0.6 to 20.5 mM with a detection limit of 0.15 mM. Moreover, the flexible electrode-based biosensor successfully determined EtOH from spiked artificial sweat samples, justifying its practical workability.