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Existing Methods
►
Method
Reversed phase or silica column
HPLC WITH PRECOLUMN DERIVATIZATION
o-phthaldehyde (OPA), phenylisothiocyanate (PITC), 9-
fluorenylmethyl chloroformate (F-MOC)
Fluorescence or UV detection
►
Advantages
Derivatization conditions (reagent and detector) can be
optimized for matrix and analytes of interest
– Greater sensitivity
Allows for using rapid reversed-phase chromatography
11
Existing Methods
►
Method
Cation-exchange chromatography
HPLC WITH POSTCOLUMN DERIVATIZATION (AOAC METHOD)
Ninhydrin, fluorescamine, OPA
Fluorescence or UV detection
►
Advantages
Can be automated resulting in increased performance
and reproducibility
Reaction efficiency less prone to sample matrix effects
Minimal sample preparation
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