424 



PHYSIOLOGICAL CHEMISTRY 



vised for use in this^test and has met with considerable favor. The 

 method of using the albumoscope is described below. 



Use of the Albumoscope. This instrument is intended to facilitate 

 the making of "ring" tests such as Heller's and Roberts'. In making 

 a test about 5 c.c. of the solution under examination is first intro- 

 duced into the apparatus through the larger arm (see Fig. 130), 

 and the reagent used in the particular test is then introduced through 

 the capillary arm and allowed to flow down underneath the solution 

 under examination. If a reasonable amount of care is taken there is 

 no possibility of mixing the two solutions and a defi- 

 nitely defined white "ring" is easily obtained at the 

 zone of contact. 



2. Nitric Acid and Magnesium Sulphate Ring Test 

 (Roberts). Place 5 c.c. of Roberts' reagent 1 in a test- 

 tube, incline the tube, and by means of a pipette allow the 

 urine to flow slowly down the side. *The liquids should 

 stratify with the formation of a white zone of precipitated 

 albumin at the point of juncture. 



This test is a modification of Heller's ring test 

 and is rather more satisfactory than that test, since 

 the colored rings never form and the consequent 

 confusion is avoided. The albumoscope (see above) 

 may also be used in making this test. 



FIG. 



130. ALBUMO- 

 SCOPE. 



3. Spiegler's Ring Test. Place 5 c.c. of Spiegler's reagent 2 in a test-tube, in- 

 cline the tube and, by means of a pipette, allow 5 c.c. of urine, acidified with acetic 

 acid, to flow slowly down the side. A white zone will form at the point of contact. 

 This is an exceedingly delicate test, in fact too delicate for ordinary clinical purposes, 

 since it serves to detect albumin when present in the merest trace (i : 250,000) and 

 hence most normal urines will give a positive reaction for albumin when this test is 

 applied. Proteose and peptone are alsp said to respond to this test. 



4. Coagulation or Boiling Test. (a) Heat 5 c.c. of urine to boiling in a test- 

 tube. (If the urine is not clear it should be filtered.) A precipitate forming at 

 this point is due either to albumin or to phosphates. Acidify the urine slightly 

 by the addition of 3-5 drops of very dilute acetic acid, adding the acid drop by 

 drop to the hot solution. If the precipitate is due to phosphates it will disappear 

 under these conditions, whereas if it is due to albumin it will not only fail to 

 disappear but will become more flocculent in character, since the reaction of a 



1 Robert's reagent is composed of i volume of concentrated HNOs and 5 volumes of a 

 saturated solution of MgSO,i. 



2 Spiegler's reagent has the following composition: 



Tartaric acid 



Mercuric chloride.. . . 



Sodium chloride 



Glycerol 



Distilled water. . 



20 grams. 



40 grams. 



50 grams. 



100 grams. 



1000 grams. 



