SALTS OF ALBUMIN AND ACIDS 



73 



work of Pauli and Hirschfeld, shows the behaviour of ro, 0-5 

 and 0-25 per cent, glutin very clearly. 



The studies of Pauli with H. Handovsky, O. Falek and M. 

 Hirschfeld on the relations of viscosity to the combination of 

 albumin with various acids are particularly interesting. 



Table 29. 



Relative Viscosities of Ox-serum Albumin 

 with different Acids. 



(Relative viscosity of the serum albumin = I -041 .) 



Let us consider first the viscosity curves of albumin chloride 

 and acetate. The former rises steeply to a maximum, while 

 the latter shows a gentle slope upwards. The difference is 

 satisfactorily explained by the lower strength of the acetic acid, 

 which leads to a less extensive formation of albumin ions, but 

 not to a repression of the dissociation of the strongly ionised 

 albumin acetate. This conception, however, fails to account 

 for the behaviour of the strong trichloracetic and sulphuric 

 acids, which display a much smaller increase in viscosity than 

 either acetic acid or even much weaker acids, such as mono- 

 chloracetic, oxalic and citric acids, which give a larger increase 

 in the viscosity of the protein. As the electrometric measure- 

 ments give no basis for the supposition that differences in degree 

 of combination occur with equally strong acids, the variation 

 in viscosity in this case can only be due to differences in hydra- 

 tion caused in some other way. Such differences in hydration 

 can be accounted for either by varied ionisation of the individual 

 protein salts, which when less ionised would be less viscous, or 

 by the difference in structure of the positive albumin ions of 



