Determination of mercury content of some pharmaceutical products by catalytic titration

Abstract

Catalytic constant-current potentiometric titration with a cathodically polarized graphite indicator electrode was applied for determination of mercury or organomercuríc compounds in some pharmaceutical products (Exomycol, Unguentum Hydrargyri, Salyrgan and Merthiosal). The Ce(IV)-As(III) system in the presence of sulphuric acid was used as indicator reaction; it is catalysed by the first excess of titrant, potassium iodide. Special attention was paid to sample decomposition. The methods are simple and fast, and can be recommended for determination of mercury or organomercuric compounds. The results are in good agreement with those of other methods. © 1982 Springer-Verlag.