High performance capillary electrophoresis - T.E.A.M.

75-µm id fused silica capillaries. Jorgenson also clarified
the theory, described the relationships between operational
parameters and separation quality, and demonstrated the
potential of high performance capillary electrophoresis
(CE) as an analytical technique. Since that time, numerous
reviews and a few books have been written describing
various aspects of CE (see Bibliography).
Principles
2.2 High performance
capillary
electrophoresis (CE)
CE can be considered an instrumental approach to electrophoresis.
In many ways the improvements in performance
resulting from using capillaries instead of slab gels are
analogous to those attained by performing chromatography
in the column rather than the flat-bed format. Further, the
mechanisms of separation are greatly extended in the
CE-format, thus extending the application range of electrophoresis.
To this end, electrophoresis is no longer limited
to separation of macromolecules and can also be used to
separate cations, anions, and neutrals in a single analysis.
2.3 Theory
2.3.1 Electrophoresis
Separation by electrophoresis is based on differences in
solute velocity in an electric field. The velocity of an ion
can be given by
v = m e
E (1)
where v = ion velocity
m e
= electrophoretic mobility
E = applied electric field
The electric field is simply a function of the applied voltage
and capillary length (in volts/cm). The mobility, for a given
ion and medium, is a constant which is characteristic of
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