title: Water determination in drugs containing thiols.
abstract: A new rapid analytical method is applied for water determination in alpha-Mono-thioglycerol and Captopril tablets containing thiols, and therefore, not amenable for direct Karl Fischer titration. The method is based on the consecutive titration first of thiol by a novel reagent, and then of water by a conventional K. Fischer reagent in the same sample and cell with the electrometric 'dead-stop' location of the end point in both titrations. The new reagent consists of iodine, potassium iodide and sodium acetate in non-aqueous medium. Estimated repeatability and accuracy of both water and thiol determinations are satisfactory.
authors.affiliation: The National Physical Laboratory of Israel, Givat Ram, Jerusalem, Israel.
authors.forename: F
authors.initials: F
authors.lastname: Sherman
authors.forename: I
authors.initials: I
authors.lastname: Kuselman
mesh_terms: D002216:Captopril / Q000032:analysis*; D005990:Glycerol / Q000031:analogs & derivatives* / Q000032:analysis; D007202:Indicators and Reagents; D015203:Reproducibility of Results; D013607:Tablets; D014867:Water / Q000032:analysis*
chemical_list: D007202:Indicators and Reagents; D013607:Tablets; D014867:Water; D002216:Captopril; C009465:thioglycerol; D005990:Glycerol