810 



URINE. 



ylamine solution allowed to flow in from a burette until the blue color 

 disappears and the solution is colorless, or, in urine poor in sugar, is yellow. 

 The sugar in milligrams is directly obtained from the amount of hydroxyl- 

 amine solution used by referring to the following reduction table : l 



For every TO cc. hydroxylamine solution used more than given in the table 

 between 49.00-15.00, subtract 0.1 milligram from the corresponding sugar value 

 and 0.2 milligram between 15.00-1.0. 



The yellow color of the urine may be somewhat disturbing for the 

 end reaction so that with little experience an error of 0.5 cc. hydroxylamine 

 solution ( = about 0.5 milligram sugar) may occur. In order to decolorize 

 the urine we can precipitate, according to ANDERSEN, with mercuric 

 nitrate, when the greatest part of the disturbing reducing substances are 

 removed, and then the excess of mercury removed by caustic soda and 

 shaking with zinc. Still simpler is the suggestion mentioned on page 

 805 with blood-charcoal after acidification with acetic acid. 



BANG 2 decolorizes by the addition of 2 cc. alcohol of 95-97 per cent 

 and a teaspoonful of blood-charcoal to 18 cc. urine, shaking and filtering 

 immediately. By this means 50 per cent of the other reducing substances 



1 This table is given with the permission of the publisher, Julius Springer, Berlin, 

 where it can be obtained at a low cost. 



Andersen, Bioch. Zeitschr., 15 and 37; Bang, ibid., 38. 



