On the relation between disease of the kidney and excretion of the alloxuric bodies / by C.F. Martin.

  • Martin, C. F. (Charles Ferdinand), 1868-
Date:
1899
Catalogue details

Licence: Public Domain Mark

Credit: On the relation between disease of the kidney and excretion of the alloxuric bodies / by C.F. Martin. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    Huppert, Arnstein, and others, to give unsatisfactory and incorrect results, the estimates in nearly all the cases being far too great for the xanthin bases. Xan- thin bases, according to this method, are first precipi- tated from the urine by copper, then subsequently the estimation is made in terms of nitrogen by the method of Kjeldahl. Now, such a method as this, which pre- cipitates the nitrogen-containing xanthin bases, lets fall also the nitrogen from other elements in the urine, and when later the total nitrogen is estimated, it becomes an index, not of the xanthin bases alone, but of any other nitrogenous elements that may be present. The final estimates, then, would yield results far in excess of what actually exists. It has been shown, for example, that certain albu- minous bodies may be present in the urine, and yet not be recognized by the ordinary tests, and these wfith their nitrogen would be readily precipitated by the copper. Again, albumin, when recognized, is extremely difficult to eliminate totally from the urine before com- mencing such a test, and if any remain in the material to be tested, it would, of course, add to the total nitro- gen estimated. The same applies, too, to the presence of potassium sulpho-cyanide, which exists in the urine in quantities equaling .5 to 1.6 mg. of nitrogen; and this, too, being precipitated by the copper-method, still further increases the amount of nitrogen estimated, which is supposed to indicate merely xanthin bases. In order the more readily to avoid such sources of error (errors, too, which, though seemingly small, actu* ally lead to astounding results when dealing with such minute portions), Salkowski has devised a method which has been proven by careful analysis to leave a minimal source of error in estimating quantities of tbe xanthin bases. This method, which consists in the preliminary precipitation by silver, avoids any danger