230 



Characteristics : 



1. In acid urine a band near F occurs, between 

 88 and 101. 



2. In alkaline urine a band between 81 and 95. 



3. Make the urine strongly alkaline with 

 ammonia, filter, add ZnCl 2 solution, but not sufficient 

 to form a permanent precipitate. 



A green fluorescence occurs, and the much 

 clearer band nearer ' b ' than the acid band. 

 Detection : 



1. If oxyhaemoglobin is present. Precipitate 

 the urobilin with basic lead acetate, then acidify the 

 precipitate, when the urobilin goes into solution. 



2. If methaemoglobin is present. Neutralize 

 the urine with carbonate of soda ; precipitate the 

 methaemoglobin with neutral lead acetate. Filter ; 

 test the filtrate for urobilin. 



BILE PIGMENTS 



Where urobilin is present, as in blackwater, the 

 colour of the foam on shaking the urine, the staining 

 of the filter paper, etc., cannot be regarded as satis- 

 factory tests. 



Detection : 



1. Gmelin-Rosenbach Test. Filter the urine 

 through filter paper (Swedish). Dry ; apply a drop 

 of nitric acid (fuming) to this, a play of colours is got. 



2. Huppert's Test. Precipitate the urine with 

 BaCl 2 . Filter ; wash the residue off the filter (per- 

 forated) with acidulated (H 2 SO 4 ) alcohol. Boil. A 

 bright green colour indicates bilirubin. 



3. Smith's Test. To ten c.c. of the urine add 

 two c.c. of dilute tincture of iodine (tincture of iodine 

 I, alcohol 10). A green ring forms at the junction 

 zone. 



