AUTOMATED PRESEPARATION DERIVATIZATION ON A CAPILLARY ELECTROPHORESIS INSTRUMENT

Fully automated derivatization prior to separation and the separation conditions were established for the determination of D-valine in an excess of L-valine by preseparation derivatization with o-phthalaldehyde and N-acetylcysteine, separation of the resulting diastereomers by micellar electrokinetic capillary chromatography and absorbance detection. The precision and detection limit with absorbance detection are a factor of three worse than those achieved with HPLC and fluorimetric detection. The application of the method at high enantiomeric excess or with chemically impure samples is limited by the detector of the instrument.