Portable instrument based on color sensor chip for on-site rapid detection of dissolved sulfides in environmental water samples

To ensure real-time validity of the detection of unstable toxic environmental pollutants, such as dissolved sulfides, we developed a portable on-site rapid analysis instrument. Through novel design of the color sensor chip-based core sensing components and the conversion between color signal and absorbance by Lambert's law , the instrument showed great performance for rapid (within 3 min) and sensitive on-site detection of sulfides in the environment. It is easy to achieve user-friendly, sample in-answer out, one-stop operation due to the touch-screen-integrated user interface of the instrument's data terminal. The detection limit of this method is 2.24 μg/L, the linear operation range is 0–1000 μg/L, and the coefficient of determination is 0.999. This instrument has been successfully applied to the on-site determination of sulfides in the Yellow River Delta and the Yantai Guangdang River in China. The portable instrument showed excellent anti-interference, good stability, and simple operation, which showed great prospects for the on-site rapid analysis of unstable targets in the environment.