Page 104 - Illustrated Pocket Dictionary of Chromatography

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ideal gas law For a perfect, or ideal gas, the relationship between
pressure, P, volume, V, amount of component, n, and temperature, T,
is:

PV = n RT

where R is defined as the gas constant. This relationship has particu-
lar importance in GC, where elution is accomplished through a tem-
perature gradient over a typical range from 50 to 250°C.
immiscible Two liquid components that form separate layers on
mixing at one or more proportions are immiscible. Immiscibility
should not be confused with solubility. For example, even though
ethyl ether and water are immiscible, they are soluble in one another:
Ethyl ether is soluble to 6.9% in water (at 20°C) and water is soluble
in ethyl ether to 1.3% (at 20°C).
immobilization The process of bonding an affinity ligand to a
support material. Because the analyte/support interaction in affinity
chromatography is based on specific three-dimensional interaction
the immobilization process is critical in that it cannot alter the inter-
action site.
imprinted phase A stationary phase that has been created by
using a molecule as a template from which the phase retains its shape
“cavity.” Phases prepared in this fashion will show a high degree of
specificity, or at least exhibit high selectivity. The largest drawback to
imprinted phases is their slow mass transfer characteristics that lead
to heavy band broadening.

Represents the interstitial volume and all
inclusion volume, V i
pore volume available in a size-exclusion column. The inclusion
volume represents the entire volume accessible to analytes that have
an effective molecular diameter less than the pore diameter in the
support material.

Illustrated Pocket Dictionary of Chromatography, by Paul C. Sadek.
ISBN 0-471-20021-2 Copyright © 2004 John Wiley & Sons, Inc.
101