Fluorescence Detection System for the Multielement Determination of Cations after Separation by HPLCFluorescence determination of cations after HPLC separation requires an unselective detection principle to achieve multielement capability. Following the principle of the photometric Zn‐EDTA‐PAR‐system, 2, 2′‐pyridylbenzimidazole (PBI) is used as a fluorescent indicator. Cations are separated on a Nucleosil 5SA column using tartaric acid as eluent. Zn is replaced by the eluent traces in a post column reactor and determined as the fluorescent Zn‐PBI‐chelate. Detection limits for Mn, Mg, Ca, Cu, Cd are 7–92 ng in 20 μL