Liquid chromatographic methods for D-serine analysis are divided into 2 types: chiral derivatization with o-phthalaldehyde
(CPA) in the presence of chiral thiols such as cysteine analogs, followed by HPLC separation on a nonchiral stationary phase, and nonchiral derivatization with fluorescent reagents followed by HPLC separation with chiral columns (3,14).
We purchased William's medium E, insulin, collagenase, Hepes, L-glutamine, penicillin, and streptomycin, NAC, BSO, GSH, o-phthalaldehyde
(OPT), and mouse fluorescein isothiocyanate (FITC) conjugate monoclonal anti-[Beta]-tubulin from Sigma (St.
Several methods have been described to determine carnosinase activity (3, 5, 7, 8,16), based on the reaction of o-phthalaldehyde
(OPA) with histidine, which is liberated from the substrate (17,18).
However, the preparation of o-phthalaldehyde (OPA) derivatives of gabapentin has been the most popular and practical approach for liquid chromatographic determinations (7-12).
Liquid chromatographic determination of mexiletine and tocainide in human plasma with fluorescence detection after reaction with a modified o-phthalaldehyde reagent.
(OPA; Fluka) was of analytical reagent grade, the mercaptoethanol was chemistry-purity grade (No.
HPLC with o-phthalaldehyde
precolumn derivatization to measure total, oxidized, and protein-bound glutathione in blood, plasma, and tissue.
In a second step, heptaminol was measured in urine following precolumn derivatization with o-phthalaldehyde
and reversed-phase HPLC with fluorescence detection (5).
Derivatization for HPLC analysis is a well-known source of overestimation, in particular o-phthalaldehyde
reacts with glutathione, and to some extent, with other sulfhydryl and amino compounds.
The determination of ALA in calibrators and plasma was performed by HPLC after prederivatization of the sample with o-phthalaldehyde