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CHLOROPLAST PIGMENTS MP THE 

 MODIFICATIONS OF CHROMATOGRAPHY 



PROCEDURES 



Tswett" s Empirical Method 



The separation of the ohloroplast pigments in adsorption columns 

 established the chromatographic adsorption procedure » This technique, 

 the formation of a narrow zone of the mixture followed by washing with 

 fresh solvent, represented a distinct advance over the earlier adsorp- 

 tion methods in which a solution of the mixture was permitted to perco- 



I S 

 late through the porous sorbent '-'o 



The methods for the recovery of the chloroplast pigments separated 



in columns have served for the isolation of various kinds of substances 



resolved by chromatographyo Collection of successive portions of the 



percolate has served for isolation of the weakly sorbed components o 



Bemoval of the individual zones from the column followed by elution of 



each substance with a suitable solvent has facilitated the recovery of 



I B 

 the strongly sorbed components '^. 



The observability of the chloroplast pigments in chromatographic 



columns provided much information about the chromatographic process » 



It revealed the dynamic sorption and desorption of the pigments, the 



distribution of the pigments in the zones, and the effect of the sorb- 



1 2 ^5 

 ent and the solvent upon the separation of the pigments » »-^o 



The experiments with the chloroplast pigments not only demonstrated 



the effectiveness of the chromatographic technique, but they also led to 



the separation of mixtures of all kinds of soluble and volatile substanoeSo 



Many of these applications were contingent upon the development of 



