Sensitive determination of manganese using flow injection and chemiluminescent detection

Abstract

The determination of Mn²⁺ in aqueous solution using a flow injection system and a chemiluminescent method of detection is reported. The Mn²⁺ ion is determined with high sensitivity and selectivity by exploiting the Mn²⁺ catalysis of the luminous oxidation of 7,7,8,8-tetracyanoquinodimethane by dissolved O₂ in alkaline solution. This reaction is sensitized by Eosin Y, and further enhanced by means of didodecyldimethylammonium bromide bilayer vesicles. The limit of detection for this reagent scheme is 4.5 ppb. A reaction mechanism and energy level diagram for this system is also presented for the first time. The method is applied to the determination of Mn²⁺ in raw and processed water.