摘要：The present work used a small amount of solvent for liquid-liquid extraction of basic chemicals in a large amount of urine sample. Two deproteinizing methods were proposed as follows. A : The pH 3.5-filtration method. A human urine sample (100 ml) was mixed with metaphosphoric acid (1 g), adjusted to pH 3.5 with HCl or NaOH-saturated solution, and filtered through a Toyo Roshi No. 5C filter paper (24 cm i.d.). The filtrate was shaken with chloroform (2.5 ml) at pH 9 (NaOH). The gelatinized chloroform layer was isolated from the urine layer. As much of the urine as possible oozing out from the isolated gel layer was removed and the gel was clarified by shaking with a bit of anhydrous sodium sulfate (less than 0.2 g). B : The pH 9-filtration method. A human urine sample (100 ml) was mixed with ferric chloride hexahydrate (1 g) at pH less than 2 with HCl to give a transparent mixture. This was adjusted to pH 9 with calcium hydroxide powder, and filtered through the filter paper. The filtrate was shaken with chloroform (2.5 ml). If the chloroform layer isolated from the urine layer was weakly gelatinized, it was clarified only by shaking.
