RegyDno} . 



Gelatin -Ctilonde 



isoelectric 



point 

 Pure eelatin 



Region of_ 

 Cu-Qelatinate 



50 



40 



30 



ZO 



10 



20,0 



17.5 



15.0 



1 2.5 



10.0 



7.5 



5.0 



2.5 







250 



225 



ZOO 



175 



150 



125 



100 



75 



50 



25 







6 



5 



4 



3 

 2 



HCl 

 cone usM 



Colorles5 Blue and turbid 



n nMM.iin_MjlM_M_iio 



6 16 32 64 12& 256 512 1024 Z04&409&8TO 



12 3.5 ib M 4,6 52 b.O M 6.3 63 63 6.3 



"77 Cu Acetate 

 15 



Fig. 7. Gelatin treated with m/16 copper acetate, washed, treated with dif- 

 ferent concentrations of HCI, and washed again. On the right side from the 

 isoelectric point gelatin exists as copper gelatinate, stained blue, practically in- 

 soluble, and with low conductivity, osmotic pressure, alcohol number, and swell- 

 ing. On the left side from the isoelectric point it exists as gelatin chloride (and 

 acetate), highly soluble, and with high conductivity, osmotic pressure, alcohol 

 number, and swelling; at the isoelectric point pure gelatin, practically insoluble. 



250 



