414 SUGAR IN URINE. 



every 10 fluid ounces of urine, or 1'34 grms. per litre. As this substance does not cause 

 alcoholic fermentation in its solutions, its identity with glucose appears to be doubtful. The 

 most active reducing agent is probably kreatinin (G. S. Johnson).] 



Teste. Any of the tests described at 149 may be used, but the urine must be free from 

 albumin. The quantitative estimation by fermentation and the titration methods are described 

 in 149. [The tests for grape-sugar described in 149 are (1) Trommer's ; (2) Fehling's ; (3) 

 Moore & Heller's ; (4) Bottger's ; (5) Mulder & Neubauer's ; (6) Fermentation test.] 



7. Worm-Midler recommends the following modification of Fehling's test. Use a 2*5 per 

 cent, solution of cupric sulphate solution, and another of 10 parts of sodio-potassic tartarate in 

 100 parts of 4 per cent, solution of soda. Boil 5 c.cm. of urine in a test-tube, while in a second 

 test-tube is boiled 1 to 3 c.cm. of the copper solution and 2*5 c.cm. of the potassio-tartarate 

 solution. The boiling of both fluids is stopped simultaneously, and after 20 to 25 seconds the 

 contents of one test-tube are added to those of the other, but without shaking the mixture, the 

 reduction taking place spontaneously. 



8. Nylander's modification of Bottger's test is also good ( 149). 



[9. Picric Acid and Potash Test. Braun showed that grape-sugar, when boiled with picric 

 acid and potash, reduces the yellow picric acid to the deep red picramic acid, the depth of the 

 colour depending on the amount of sugar present. Dr Johnson uses this test for detecting the 

 presence of sugar in urine, and also for estimating the amount of sugar present, the depth of the 

 red colour obtained in boiling being compared with a standard dilution of ferric acetate. In 

 doing the test, use 1 drachm of urine, h a drachm of liquor potassfe, and 10 minims of picric 

 acid solution ; make up to 2 drachms with distilled water, and boil the mixture for one minute. 

 This test indicates the presence of 0*6 grain of sugar per fluid ounce of normal urine. Dr 

 Johnson claims for this test that it possesses all the advantages of the other tests, while it is 

 not affected by uric acid or any other normal ingredient of urine ; neither does the presence of 

 albumin interfere with the action of the test as it does with all the forms of copper testing.] 



[10. Indigo-carmine Test. A blue solution of this substance, when boiled with diabetic 

 urine containing sodic carbonate, changes from a blue to a violet, purple, red, yellow, and 

 finally, straw-yellow colour. After cooling and exposure to the air, the various colours are 

 obtained in the reverse order until the mixture becomes blue again. Dr Oliver uses this test in 

 the form of test-papers. One bibulous paper is impregnated with the indigo-carmine and the 

 other with sodic carbonate. Drop one of the test-papers and a sodic carbonate paper into a 

 test-tube containing 1 inches of water, heat gently, when a blue solution is obtained. Add 

 the urine slowly, one drop at a time, and boil the mixture, observing any change of colour by 

 holding the tube against a white surface below the level of the eye. Uric acid and urates, which 

 reduce Fehling's solution, do not affect the carmine test, nor does kreatinin, although it reacts 

 with the picric acid test.] 



[Quantitative Estimation. (a) Fermentation Test ( 150). Take 4 oz. (120 c.c. ) of the urine ; 

 add a lump of German yeast, about the size of a walnut, lightly cork the bottle, and place it 

 aside for twenty-four hours in a moderately warm place, e.g., on the mantelpiece. Take the 

 specific gravity before and after the fermentation. Thus, if the specific gravity be 1038 before 

 and 1013 afterwards, the difference or " density lost" is 25, which gives 25 grs. of sugar per 

 fluid oz. (Roberts). If it be desired to get the percentage, multiply the density lost by 0'23, 

 thus 25 x 0-23 = 5-69 in 100 parts.] 

 [(b) Volumetric Analysis. 10 c.c. of Fehling's solution = *05 gramme of sugar. 

 1. Ascertain the quantity of urine passed in twenty-four hours. 2. Filter the urine, and 

 remove any albumin present by boiling and filtration. 3. Dilute 10 c.c. of Fehling's solution 

 with about twenty times its volume of distilled water, and place it in a white porcelain capsule 

 on a wire gauze support under a burette. (It is diluted because any change of colour is more 

 easily observed.) 4. Take 5 c.c. of the urine, and 95 c.c. of distilled water, and place the diluted 

 urine in a burette. 5. Gradually boil the diluted Fehling's solution, and whilst it is boiling 

 gradually add the diluted urine from the burette, until all the cuprous oxide is precipitated as 

 a reddish powder, and the supernatent fluid has a straw-yellow colour, not a trace of blue re- 

 maining. Read off the number of c.c. of dilute urine employed. Say 36 c.c. were used that, 

 of course, represents 1*8 c.c. of the original urine. Suppose the patient passes 1550 c.c, 

 as 1-8 c.c. of urine reduced all the cupric oxide in the 10 c.c. of Fehling's solution, it must 

 contain *05 gramme sugar, hence, 



1 '8 : 1550 : : *05 : 237 '5 grammes of sugar passed in 24 hours.] 



[Preparation of Fehling's Solution. 34 64 grammes of pure crystalline cupric sulphate are 

 powdered and dissolved in 200 c.c. of distilled water ; in another vessel dissolve 173 grammes 

 of Rochello salts in 480 c.c. of pure caustic soda, specific gravity 1*14. Mix the two solutions, 

 and dilute the deep coloured fluid which results to 1 litre. N.B. Fehling's ought not to be 

 kept too long ; it is apt to decompose, and should therefore be preserved from the light, or pro- 

 tected with opaque paper pasted on the bottle. Some other substances in urine, e.g., urates 

 and uric acid, reduce cupnc oxide. ] 



