title: Fluorimetric sequential injection determination of magnesium using 8-hydroxiquinoline-5-sulfonic acid in a micellar medium.
abstract: A fluorimetric sequential injection method for the determination of magnesium is proposed. The system is based on the complex formation between Mg(II) and 8-hydroxyquinoline-5-sulfonic acid (HQS). The reaction was carried out in the presence of ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) as a masking agent. Cetyltrimethylammonium chloride (HTAC) was employed as a fluorescence enhancer. The influence of several variables, such as reagent concentration, volumes and pH has been investigated. The reagent was prepared in a 0.1 M Tris-HCl buffer solution (pH 9). A detection limit of 12 mug l(-1) magnesium was obtained. The proposed method was applied to the determination of magnesium in natural waters.
authors.affiliation: Department of Analytical Chemistry, Materials and Reagents Institute (IMRE), University of Havana, Havana, Cuba.
authors.forename: G
authors.initials: G
authors.lastname: de Armas
authors.forename: A
authors.initials: A
authors.lastname: Cladera
authors.forename: E
authors.initials: E
authors.lastname: Becerra
authors.forename: J M
authors.initials: JM
authors.lastname: Estela
authors.forename: V
authors.initials: V
authors.lastname: Cerdà