Sodium fluoride for pharmaceutical use needs to comply with USP requirements. The actual monograph (USP 42) uses three different methods for the identification, the assay, as well as the content of chloride as an impurity. Ion chromatography allows the measurement of these three parameters in two determinations on a single system. In the course of the USP monograph modernization, this ion chromatographic approach brings an increased ease of use for this type of analysis.
The presented IC method is suitable to determine sodium fluoride and its impurities according to the USP Monograph «Sodium Fluoride». The method helps manufacturers of dental care products to determine fluoride content as well as impurities more easily in toothpaste.