ABSTRACT
What may be called chromatographic effects today were already in use some 2000 years ago. Dyers were accustomed to judge the quality of their dyes and, in particular, to detect the presence of adulterants by letting a drop of solution spread out on a piece of cloth or paper (papyrus). The fringe of colors formed at the boundary of the spot was a useful diagnostic. This could be the root of paper chromatography (PC). Around the same time, column chromatography was born in the oil industry, where crude oils were puried by allowing them to percolate through beds of carbon. However, as with many great discoveries the exact origin of the process could not be pointed out, although a few can be appreciated for giving due importance to the process by using it for the separation, purication, and identication of compounds. The rst to give convincing evidence of the power and versatility of the process was M. S. Tswett, a botanist, who in 1906 isolated the principal plant pigments by passing them in a solution of petroleum ether through a column of powdered chalk. Chromatography based on the differential partition between two immiscible solvents was rst described, in 1941, by A. J. P. Martin and R. L. M. Synge. In this process, water was xed within silica gel, the mobile phase used was chloroform, and the amino acids of a protein were analyzed. Subsequently, other classes of compounds, for example, antibiotics, were analyzed. Today, the technique has developed in all dimensions as perhaps the single most powerful analytical and preparative method available in the laboratory.
