ION EXCHANGE 



397 



pass. The neutrals and histidine are put through another cohimn of 

 IRC-50 at pH 4.7 which retains the histidine, thus effecting its separation 

 from the neutral amino acids. The arginine and lysine are separated by 



Protein 



hydrolyzote 



(HCl) 



n 



Amb. 

 IR-4B 



Amb. 

 1R-4B 



HCl 



odsorbed 



Eluted 



with 



ocetote 



Glutamic and 

 aspartic ocids 



Amb. 



IRC-50 



pHZO 



Eluted 

 with 

 HCl 



Amb. 



IRC-50 



pH4.7 



Amb. 

 lRA-400 



Eluted 

 with acetate 



Lysine 



Arginine 



Fig. 9-10. Scheme for separation of amino acids. [From Juines C. Winters and Robert 

 Kunin, Ion Exchange in the Pharmaceutical Field, hid. Eng. Chem., 41 : 460-463 (1949)1. 



use of a strongly basic anion exchanger (Amberlite IRA-4()0) which 

 retains the lysine but permits the arginine to pass through. 



Ion-exchange chromatography has been successfully employed to sep- 

 arate almost all the common amino acids. A satisfactory method has 

 been based on the use of a sulfonated hydrocarbon cation exchanger 



