87 / 196
7
Existing Methods
►
Gas Chromatography
Precolumn derivatization to less polar and more volatile
OTHER METHODS
compounds
FID or MS detection
►
Capillary Electrophoresis
Precolumn, postcolumn, and oncolumn derivatizations
Fluorescence or UV detection
►
HPAEC-PAD
D i ti ti
t
i d
er va za on no requ re
►
HPLC-MS/MS
Derivatization not required
Mainly clinical applications to date
13
Challenges
►
Multiple analytes with varying functional groups make
utilizing one method difficult
►
HPLC with Precolumn Derivatization
Sample matrix can effect reaction efficiency
Reaction products can be unstable
►
HPLC with Postcolumn Derivatization
High reagent consumption
Limited variety of reagents
L
ti
( 60 i )
ong run me ~ m n
Potential for loss of resolution
Less sensitive
14