SALTS OF ALBUMIN AND ACIDS 



75 



figure following give the results of investigations on serum 

 ilbumin. 



Table 30. 



(a of the pure albumin = 1-02 ; 

 ox-serum albumin concentration = 1-07 per cent.} 



These and other similar experiments show that for an increase 

 in rotation it is not the strength of the acid that is decisive. 

 Thus, oxalic acid is more effective than the much stronger 

 trichloracetic acid or 

 sulphuric acid, and 

 acids as different in 

 strength as trichlor- 

 acetic and acetic acids 

 have much the same 

 effect on the optical 

 rotation. In this 

 respect there is a 

 notable agreement 

 between the curves 

 for viscosity and for 

 optical rotation of the 

 protein salts of the 

 various acids. 



On the other hand, 

 the optical rotation fails to give the maximum value and 

 subsequent decrease that is so characteristic of the viscosity, 

 e.g., of hydrochloric acid and proteins. The rotation tends 

 rather to remain constant after reaching the maximum. It 

 is thus the general formation of salts of albumin, and not 



0-1 



0'01 O'OZ. O'OS OW O'OSn 

 FIG. 1 8. Rotation curves with various acids. 



