Integrated pervaporation/detection for the determination of fluoride in pharmaceuticals.
A selective dynamic method for the determination of fluoride in pharmaceuticals based on the integration of pervaporation and potentiometric detection in a laboratory-made module is proposed. The analyte was continuously converted into volatile trimetylfluorosilane by reaction with hexamethyldisilazane, injected into a donor stream and accepted in a basic buffer solution after pervaporation. The method thus developed has a determination range between 1.5 and 200 mg l-1, precision (expressed as R.S.D.) of 3.4%, and has been applied to the determination of fluoride in different pharmaceutical products, with yields ranging between 90.6 and 100.3%. B.V.
Gámiz-Gracia
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Analytical Chemistry Division, Faculty of Sciences, University of Córdoba, Spain.
de Castro
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D002021:Buffers; D005459:Fluorides / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D007700:Kinetics; D017646:Organosilicon Compounds; D011199:Potentiometry; D014297:Trimethylsilyl Compounds
D002021:Buffers; D007202:Indicators and Reagents; D017646:Organosilicon Compounds; D014297:Trimethylsilyl Compounds; C038077:trimethylfluorosilane; C024548:hexamethylsilazane; D005459:Fluorides