High performance capillary electrophoresis - T.E.A.M.
High performance capillary electrophoresis - T.E.A.M.
High performance capillary electrophoresis - T.E.A.M.
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Modes<br />
EOF<br />
No flow<br />
Figure 22<br />
Elimination and reversal of electroosmotic<br />
flow using a cationic surfactant<br />
EOF<br />
Surfactant concentrations above the CMC significantly alter<br />
the mechanism of separation. This leads to another mode<br />
of CE, micellar electrokinetic chromatography, which is<br />
discussed in section 3.2.<br />
3.1.1.4 Chiral selectors<br />
Chiral analysis is becoming increasingly important in both<br />
the drug and food industries. Currently, chiral separations<br />
are primarily performed by HPLC and GC. These analyses<br />
can be complicated and difficult to optimize. In addition,<br />
chiral stationary phases are usually expensive.<br />
In contrast to the use of chiral stationary phases, chiral<br />
analysis by CZE usually involves the addition of a chiral<br />
selector to the running buffer. These selectors can be<br />
cyclodextrins, crown ethers, bile salts, copper (II)-aspartate<br />
complexes, for example. Compared with chiral chromatography,<br />
which uses a vast array of chiral phases to alter<br />
selectivity, the high efficiency of CE results in the use of a<br />
relatively small number of chiral selectors.<br />
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