Colorimetric and Electrochemical Dual-Signal Method for Water Toxicity Detection Based on <i>Escherichia coli</i> and <i>p</i>-Benzoquinone
Dengbin Yu, Rongbing Li, Xiaoxuan Sun, He Zhang, Hongwen Yu, Shaojun Dong
Abstract
The development of simple and rapid toxicity detection methods has important practical significance. In this work, a dual-signal method with colorimetric and electrochemical properties for water toxicity detection was proposed for the first time based on a rapid color reaction between Escherichia coli (E. coli) and p-benzoquinone (BQ). Here, E. coli was used as a biocatalyst and BQ was used as a mediator. An IC50 value of 0.75 mg L–1 for Cu2+ was obtained using a two-step electrochemical detection method. Strikingly, toxicity could also be estimated visually by the naked eye, and the minimum detection limit was 3.2 mg L–1 for Cu2+. The dual-signal toxicity detection method extends the function of BQ, and the result is more reliable than the traditional single-signal method. This simple and rapid toxicity detection method shows certain application prospects.