HANDBOOK FOR BIO-CHEMICAL LABORATORY. 



2. Serum albumin may also be precipitated from the fil- 

 trate, after the precipitation of the serum globulin, by means 

 of acetic acid about 1$. Filter after a few hours, press the 

 precipitate between filter-paper, dissolve in water, neutralize 

 by the addition of alkali, and remove salts by means of dial- 

 ysis. The serum albumin is obtained from this salt-free solu- 

 tion as above directed. 



Properties. In the dry state serum albumin forms a trans- 

 parent, gummy, brittle, hygroscopic mass or a white powder, 

 readily soluble in water, forming a clear solution with a spe- 

 cific rotatory power, for a solution saturated with JSTaCl, of 

 (a) D = 62.6 to 64.6. The coagulation temperature is 

 + 70 to 75 C., but varies with the varying concentration 

 and the amount of salts. Its solutions are precipitated by 

 alcohol and ether. 



Oy-Albumin. 



Preparation. 1. The white of several hen's eggs (free 

 from yolk) is subdivided by cutting with a scissors or by 

 beating violently, filtered through linen (free from starch), 

 and then treated with an equal amount of water. A precipi- 

 tate will form, and this must be removed by filtration. Sat- 

 urate the filtrate at 20 C. with very finely powdered mag- 

 nesium sulphate (MgS0 4 -f- 7H a O), which is done by adding 

 small portions of the salt at a time and constantly stirring. 

 After completely saturating, remove the precipitated globu- 

 lins by filtration, and thoroughly dialyze the filtrate until a 

 portion removed and treated with BaCl 2 does not give any 

 reaction for sulphates. Evaporate the solution (which greatly 

 increases in volume during dialysis) at 40-50 C. in a flat 

 dish, and allow this concentrated solution to undergo dialysis 

 again ; and, lastly, evaporate to dryness at the above-mentioned 

 temperature. 



2. Ov-albumin may also be obtained by saturating the fil- 



