# Nanostructured Carbon and Gold Screen-Printed Electrodes for Sensitive Detection of Benzisothiazolinone in Environmental Water Samples

## TL;DR

This paper presents a new method using carbon and gold electrodes to detect a harmful chemical in river water, which could help with environmental monitoring and regulation.

## Contribution

The study introduces novel carbon- and gold-based screen-printed electrodes with enhanced sensitivity for detecting benzisothiazolinone in environmental samples.

## Key findings

- Square-wave voltammetry improved sensitivity by two orders of magnitude for carbon-based electrodes and 30-fold for gold-based electrodes.
- The lowest detection limits achieved were 40 nM for carbon and 80 nM for gold nanoparticle-based electrodes.
- Carbon-based electrodes showed good recovery in river water with minimal interference from common ions or saccharin.

## Abstract

Benzisothiazolinone (BIT) is a commonly used biocide in water-based products, which can enter the environment from household and personal care products, as well as from leaching off building facades and roofs due to rainfall, eventually reaching rivers through stormwater runoff and raising ecological concerns due to its high aquatic toxicity. Detecting benzisothiazolinone, particularly in the environment is crucial due to health and regulatory requirements. This study explores electrochemical techniques and conductive nanomaterials for detecting BIT in environmental samples. Carbon- and gold-based screen-printed electrodes (SPEs) with distinct morphologies were investigated: carbon electrodes as nanoparticles (SPE-C) and single-wall carbon nanotubes (SPE-SWCNTs), and gold electrodes as nanoparticles (SPE-Au-BT) and thin films (SPE-Au-AT). Cyclic voltammetry and square-wave voltammetry (SWV) were optimized, with SWV demonstrating superior sensitivity—showing a two-order improvement with carbon-based electrodes and a 30-fold enhancement with gold-based electrodes. The lowest detection limits were 40 nM for carbon and 80 nM for gold nanoparticle-based electrodes. SPE-C achieved good recovery in river water, confirming its effectiveness for BIT monitoring with minimal interference from common ions or saccharin. These sensors can be easily used for everyday detection and monitoring of BIT in river water, ensuring a screening programme that supports the development of adequate regulatory guidelines.