Online ligand exchange in the determination of weak acid dissociable cyanide by gas diffusion-flow injection analysis

► Online ligand exchange method has been developed for WAD cyanide determination. ► Ligand combination of TU and PEHA allows complete online recovery of WAD cyanide. ► It provides a fast, sensitive, and reproducible means of determining WAD cyanide. ► It was tested in real samples and showed good agreement with the standard method.