Alas, where there once was togetherness is now a separation. In chromatography, explains Pirkle, what separates disparate entities in a chemical mixture, such as a cell extract of thousands of proteins or a sample of water with different pollutants, is the attraction of its component members for a surer thing--a solid. Depending upon the strength of this relationship, the different parties will separate from each other at varying rates.
In chromatography parlance, a chemical mixture is dissolved in a gas or a liquid called the mobile phase, which pushes the sample through a cylindrical glass or Plexiglas column. The column is often filled with a solid--the stationary phase--that has various affinities for the components of the mixture. As the mobile phase carrying the dissolved components of the mixture weaves its way through the stationary phase, a separation ensues.
But, unlike in marriages, separation in chromatography is a good thing. The ...
