Determination of Sulfide and Cyanide Using Integrated Pulsed Amperometric Detection on a Disposable Silver Electrode

ecause of their toxicity, the determination of free sulfide and cyanide is increasingly important. Liquid chromatography with amperometric detection on silver electrodes offers excellent sensitivity for this application. The development of disposable silver electrodes ushers in a new era for reproducibility and ease of use. Liquid chromatography with dc amperometry is a sensitive method for the separation and detection of sulfide and cyanide. However, when sulfide and cyanide are detected in real samples by dc amperometry on a silver working electrode, the electrode surface is frequently fouled (1). Although a fouled electrode can be reconditioned, the process is cumbersome and time consuming. Recently, a method was published showing that the application of a pulsed waveform is an effective method of preventing electrode fouling (1). In this note, we show that the combination of an optimized waveform with disposable silver electrodes provides a rugged, simple, and stable method for the determination of sulfide and cyanide.