Displacement thin-layer chromatography

Thin-layer chromatography has several advantages in comparison to column ch romatography, e.g., simultaneous separation of several samples, easy realiz ation of two-dimensional separation, direct observation of both the chromat ographic development and the separation using colored compounds, sensitive and easy detection of the spots with specific spray reagents. The entire pr ocedure, i.e., loading, development, and evaluation are relatively simple. An additional feature is the optimization possibilities of mobile phase flo w velocity, based on the complexity of driving force where capillarity resu lts in a concave flow profile that may be counterbalanced by convex profile of laminar flow. Displacement thin-layer chromatography has the advantages of planar arrangement of the stationary phase, and opens new possibilities for analytical separations. This paper outlines basic features of planar displacement chromatography, i ncluding differences from elution chrom- atography, and that of column disp lacement chromatography, the possibility of using spacer displacement chrom atography. Parameters limiting displacement chromatography, and their optim ization to achieve better separation are discussed.