抄録
A simple colorimetric assay method of methylmethionine sulfonium derivatives (MMSD) in pharmaceutical preparation was established using potassium 1,2-naphthoquinone-4-sulfonate as a coloring reagent. MMSD was purified as phosphotungstate from its decomposition products and other impurities. The presence of borate as a component of buffer solution in reaction mixture had advantages for the lowering the blank value and for the improvement of the recovery rate.
