Page 180 - Illustrated Pocket Dictionary of Chromatography

182 SOAP CHROMATOGRAPHY

n 1sinf 1 = n 2sinf 2

soap chromatography See ion-pair chromatography.

solid-phase extraction (SPE) SPE is a column sample prepara-
tion technique that concentrates and separates analyte for other
sample components.

Shown above are some common SPE column (top row) and cartridge (bottom row)
configurations. The columns are processed by pulling a vacuum. Vacuum manifolds
having 6–24 ports have been produced in order to process multiple samples simul-
taneously. Cartridges are commonly used when a low number of samples are
processed. These are fit to the end of a Luer-Lok syringe and processed by apply-
ing positive pressure. Finally, the column and cartridge designs have also been
designed for use in automated SPE processing units.

solubility limit The maximum amount of substance that can be
dissolved under a set of conditions is defined as the solubility limit of
the substance.

solubility parameter, d Mathematically defined as:

d= (DEV ) 12
v