Analysis of Chiral Drugs in Body Fluids - Chiral Separations by Capillary Electrophoresis - page 358

12.5 CONCLUDING REMARKS
Due to the high resolution power, electromigration techniques have been increas-
ingly used for the stereoselective analysis of drugs and metabolites in biological
samples. Reliable methods have been obtained after elaborated validation proce-
dures. Precision requirements have been attained by using well-designed capillary
washing procedures before each run, by using an internal standard and/or by taking
careful control of analytical conditions, including the prevention of buffer depletion
and temperature control. The sensitivity required for the analysis of trace amounts
of chiral drugs and their metabolites in biological samples has been enhanced by
using more sensitive detection systems, by stacking procedures and/or by sample
preconcentration. Finally, we can conclude that electromigration techniques might
be powerful alternatives to the well-established HPLC-based methods for the enanti-
oselective analysis of chiral drugs and their metabolites in biological samples, with
the advantages of low costs, low-waste production, short analysis time, and easy
method development.
ACKNOWLEDGMENTS
The authors wish to express special gratitude to Professor Dr. Heni Sauaia for his
important encouragement and valuable suggestions and also to Dr. Franciane M. de
Oliveira for her assistance in the revision which provided essential help in the prepa-
ration of this chapter. The authors are grateful to FAPESP and CNPq.
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