Determination of Fluoride in Mouthwash Using Flow-injection Analysis with Spectrophotometric Detection
Benedito Roberto de Alvarenga, Wesley Lira Gabriel, Denílson Mendes de Oliveira, Cesar Reis, Reinaldo Francisco Teofilo, Vagner Bezerra dos Santos and Willian Toito Suarez
Pages 208-214 (7)
In this work, the development of flow system that is simple, precise and accurate for determining fluoride in
mouthwash is described. The determination of fluoride was based on the on-line formation of a Fe(III)–salicylate complex,
which is consumed in the presence of fluoride, generating the colourless hexafluoroferrate(III) complex ion, [FeF6]3-.
The proposed procedure exhibits a linear concentration range of 8.0 × 10-5–1.2 × 10-3 mol L-1, a detection limit of 3.5 x
10-5 mol L-1, a higher sampling frequency of 44 h-1 and relative standard deviations below 0.2%. The interference of the
red colour of the samples was removed using waste-seed specimens of Mabea fistulifera Mart. as a biosorbent material.
Biosorbent material, flow injection analysis, fluoride, hexafluoroferrate(III) complex, mouthwash,
Departamento de Quimica, Universidade Federal de Vicosa - UFV, Centro de Ciencias Exatas e Tecnologia, 36570-900, Viçosa, MG, Brazil.