CHAPTER 8 



PAPER CHROMATOGRAPHY 



General Methods — Chromatograph Chamber; Filter Paper; Application of Sample; 

 Solvents; Detection of Spots; Quantitative Aspects: Color comparison; Determination 

 of spot area; Elution; Use of an Electrical Field. Orcianic Separations. Inorganic 

 Separations. Applications. 



The development of chromatography, a process destined to have wide 

 apphcation, is generally credited to the botanist M. 8. Tswett, who used 

 the method in 1906 for the separation of plant pigments. However, it 

 has been pointed out that perhaps others in the field of petroleum chem- 

 istry had preceded him (1). The method is essentially a countercurrent 

 distribution process in which the substances to be separated become dis- 

 tributed between a solvent and solid phase. The general procedure, 

 which is exceedingly simple, consists in passing the solution to be analyzed 

 through a column of adsorbent, thus bringing the substances into contact 

 with the solid interface at which they concentrate. As the substances are 

 moved down the column with the addition of solvent, the more weakly 

 adsorbed ones will move faster, thereby effecting the separation. This 

 method is variously called chromatography , T swett-colimin analysis, chro- 

 matographic adsorption analysis, or differential countercurrent adsorption 

 analysis. The general references may be consulted for details of tech- 

 nique and application (2 to 6, 10a). Also in the early 1900's, Gop- 

 pelsroeder devised a separation procedure called capillary analysis which 

 was based on the use of filter paper and was actually the forerunner of 

 present-day paper partition chromatography. 



The term partition chromatography is now used to designate methods of 

 separation based upon the distribution of substances between two liquid 

 phases, one of which is mobile and the other essentially fixed to a support 

 by sorption. In an early application of this principle, Martin and Synge 

 (11) separated acetylated amino acids by use of silica gel to hold the fixed 

 liquid phase, water. A most important development was the modifica- 

 tion of this procedure by Consden, Gordon, and Martin (12) in which the 

 silica gel was replaced by filter paper as the inert support. Thus the 

 process of paper partition chromatography, or. more simply, paper chro- 



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