抗菌性物質の化学的定量法 (第5報)

クロルテトラサイクリンの比色定量法

抄録

Aqueous solution of chlorotetracycline hydrochloride, when warmed for 45 minutes at 30° with the addition of aminopyrine, sodium hydroxide, and potassium ferricyanide, colors reddish violet and this color transits to the amyl acetate layer when the aqueous solution is acidified with acetic acid and shaken with amyl acetate. The optical density of this colored acetate layer was measured at 564mμ to make colorimetric determination of chlorotetracycline. The presence of oxytetracycline and tetracycline in less than 20% amount makes it possible to determine chlorotetracycline with below 2% accuracy. Determination of chlorotetracycline hydrochloride, in an aqueous solution, allowed to stand for a long period of time and expected to have undergone a certain amount of decomposition, by the biological assay, hydrochloric acid method, and the present method gave well agreeing value. It was also found that the markedly decomposed solution determined by the present method gave values approximating those by biological assay than the values by the hydrochloric acid method.