title: Spectrophotometric determination of fluoride in dosage forms and dental preparations.
abstract: The method is based upon the reaction between fluoride ions and the coloured complex of Fe(III) with methyl salicylate to form the stable, colourless hexaflouride complex of iron. The conditions of the method (pH, time and combination ratio) were studied and a standard curve was obtained for 0.01-0.08 mg NaF ml-1, at 525 nm. A study was conducted on interference with complexing anions of Fe(III), cations that react with fluoride ions and with common ingredients of dosage forms and dental preparations. The method was validated and the results showed good precision (100.16 +/- = 2.33%) comparable with that of other analytical methods. Good results were obtained in the spectrophotometric determination of fluoride ions in a stomatological gel and in a toothpaste.
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, University of Medicine and Pharmacy, Iuliu Hatieganu, Cluj-Napoca, Romania.
authors.forename: R
authors.initials: R
authors.lastname: Săndulescu
authors.forename: E
authors.initials: E
authors.lastname: Florean
authors.forename: L
authors.initials: L
authors.lastname: Roman
authors.forename: S
authors.initials: S
authors.lastname: Mirel
authors.forename: R
authors.initials: R
authors.lastname: Oprean
authors.forename: P
authors.initials: P
authors.lastname: Suciu
mesh_terms: D003802:Dentifrices / Q000032:analysis*; D004304:Dosage Forms; D005290:Ferric Compounds / Q000737:chemistry; D005460:Fluorides, Topical / Q000032:analysis*; D005782:Gels / Q000032:analysis; D011199:Potentiometry; D012459:Salicylates / Q000737:chemistry; D012969:Sodium Fluoride / Q000032:analysis*; D013056:Spectrophotometry, Ultraviolet / Q000379:methods; D013607:Tablets / Q000032:analysis; D014100:Toothpastes / Q000032:analysis
chemical_list: D003802:Dentifrices; D004304:Dosage Forms; D005290:Ferric Compounds; D005460:Fluorides, Topical; D005782:Gels; D012459:Salicylates; D013607:Tablets; D014100:Toothpastes; D012969:Sodium Fluoride; C033069:methyl salicylate; C049467:ammonium ferric sulfate