几种含氮有机药物中氮含量的容量测定法

含氮有机药物为数甚多,有一部分各国药典已有了规定测定的方法,还有一部分尚无一定测定的方法。如非那西汀、咖啡因、茶碱等,方法比较麻烦,结果难得令人满意;如巴比妥等,英、美、日等药典都用提取法;核黄素的测定,美国药典系用萤光法;英、日药典系用凯氏法测定氮的含量。都不是理想的方法,如提取法不但手续麻烦,而且不易得到准确的结果。萤光法所用仪器,非普通试验室所能置备;凯氏法不但蒸馏麻烦费时,同时有的含氮有机物不容易或者不能使全部的氮变为氨。于是我们就中国药典中含氮药物尚无一定测定方法者十四种,用凯氏直接滴定法测定其氮含量,其中有几种所得的结果与理论值相差较大,为了要证明这几种药物未能破坏完全,抑是有一部分氮变成挥发性的氮化合物,我们进行了凯氏杜马氏连接装置的试验。

VOLUMETRIC DETERMINATION OF NITROGEN CONTENTS IN CERTAIN ORGANIC MEDICAMENTS

Volumetric Determination of nitrogen content in 14 drugs,most of which are official in Chinese Pharmacopoeia 1953,by means of modified Kjieldahl method without distillation were described.Ammonium sulfate formed during Kjieldahl digestion combined itself with formaldehyde after the solution was neutralized carefully. The free acid liberated according to the following reaction was then titrated. 4NH_4~++6HCHO(CH_2)_6N_4+4H~++6H_2O It was found that Antipyrin,pyramidon,sodium barbital and pentobarbital sodium...