Green Silver Nanoparticle for Colorimetric Determination of Cyanide in Water Samples

Cyanide ion is highly toxic to human. Cyanide ion is mainly used in processes like electroplating and extraction of silver and gold. Therefore, it can enter the environment and pollute soil and water. In the present work, a colorimetric method based on silver nanoparticle (AgNP) was proposed for detection and determination of cyanide ion. Silver nanoparticle was prepared by carbon dots as reducing agent. Volume of AgNP and concentration of sodium hydroxide were optimized for determination of cyanide ion by AgNP. It was observed that greenly synthesized AgNP can serve as reagent in detection and determination of cyanide ion. In the presence of sodium hydroxide, a method was optimized and a robust model with linear range of 4.0-100.0 μM, limit of detection of 3.8 μM and limit of quantification of 12.7 μM was obtained. In the method presented, the color change of AgNP from yellow to colorless in the presence of cyanide ion was observed. Environmental water samples including spring, well and wastewater were successfully analyzed by this method, which is simple and inexpensive.