Mixed Ligand Complex of Lanthanum(III) and Alizarine-Complexone with Fluoride in Micellar Medium for Spectrophotometric Determination of Total Fluorine
A technique for direct spectrophotometric determination of total fluorine in products for oral hygiene using a mixed ligand complex La(III) and alizarin-complexone with fluoride ion in the presence of a non-ionic surfactant has been developed. A number of complexes of different stoichiometry formed in the system has been found. The La:alizarin-complexone:F- = 1:2:1 complex was shown to be used as an analytical form. The complex in the presence of Tween 80 is characterized by the molar absorptivity ε620 = 11000 mol∙dm-3∙cm-1.