[Examinations of the analytic reliability of N-acetylneuraminic acid determinations according to the pharmacopoeia of the GDR].

Abstract

A further investigation of the Arzneibuch (Diagnostic Laboratory Methods) GDR-method for the estimation of N-acetylneuraminic acid was performed. By this was found, that the formation of the dye complex is not still finished after 15 minutes and the reaction product shows an exponential decomposition. The decomposition rate was much greater in the reaction medium than in n-amyl alcohol. By increasing the ferric (III)-chloride concentration the specificity of the method could be essentially improved. With the fivefold ferric (III)-chloride concentration the physiological concentrations of the protein bound monosaccharides of the serum changed the accuracy of the measuring results by less than or equal to 2.0%.