Abstract
Tungstic acid protein free blood filtrate was hydrolyzed with dilute mineral acid for two hours, then made strongly alkaline with ammonia and evaporated slowly to a small volume. After filtration, the filtrate was made alkaline with ammonia and precipitated with silver chloride in ammonia. The washed precipitate was decomposed and picric acid added. The resulting crystaline precipitate was purified and one analysis proved to have 29.3 per cent. nitrogen. It melted at 281 C. After removal of the picric acid, the residue proved to have approximately 38 per cent. nitrogen. It precipitated with gold chloride and ammoniacal silver. It gave no color with Nessler's solution and no blue color with alkaline phosphotungstate.
Tungstic acid filtrate was precipitated with silver, the precipitate broken up and the filtrate precipitated with neutral lead acetate in acid solution. The lead precipitate was decomposed and then gave a strong pentrose reaction with orcin and an absorption band between the D and the E. With napthoresorcin the color produced did not shake out with ether or benzol. There was no xanthin test nor was there any trace of blue with phosphotungstate.
If the blood filtrate was first hydrolyzed with acid and then the same procedures carried out no traces of pentrose reaction could be found.
If the blood filtrate mas precipitated with silver, then lead, and the filtrat from lead sulphide was hydrolyzed with acid subsequent addition of silver precipitated the nitrogen containing portion of the substance, while the substance producing the pentrose reaction remained in the filtrate.
If the inorganic phosphates are removed from the filtrate from lead sulphide there is no immediate test for phosphates with ammonium molybdate. If, however, this same filtrate, free from inorganic phosphates be hydrolyzed with dilute acid before the test is done a yellow precipitate characteristic of phosphates appears immediately.
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