Application study of RGB color extraction in water toxicity detection

In this work, a colorimetric biosensor based on the rapid color change of Escherichia coli DH 5α (E. coli) and p-benzoquinone (BQ) was introduced to evaluate water toxicity. Here, dark brown quinhydroquinone (QHQ) was obtained from the reaction between E. coli and BQ. The inhibition ratios were calculated by RGB (red, green, blue) values of samples or oxidation current of hydroquinone (HQ). Here, RGB technology was used for biotoxicity assessment for the first time. The results suggested that the biosensor-based RGB has an obvious dose-dependent response. The IC₂₀ values of Hg²⁺ and Cu²⁺ obtained based on RGB values were 1.0 and 1.5 mg L^-1, respectively. This biosensor can be used to detect quickly toxicity of the Cu²⁺ and Hg²⁺ in water without complicated operation steps. Therefore, the biosensor has potential application value in the field of water toxicity detection.