Enantiomeric separation and detection by high-performance liquid chromatography-mass spectrometry of 2-arylpropionic acids derivatized with benzofurazan fluorescent reagents.

The enantiomneric separation and the detection of 2-arylpropionic acids after derivatization with the fluorescent reagents with a benzofurazan structure, (S)-(+)-4-(N,N- dimethylaminosulphonyl)-7-(3-aminopyrrolidin-1-yl)-2,1,3-ben zoxadiazole ((S)-DBD-Apy), (R)-(-)-4-nitro-7-(3-aminopyrrolidin-1-yl)-2,1,3- benzoxadiazole ((R)-NBD-Apy), 4-N,N-dimethylaminosulphonyl-7-piperazino-2,1,3-benzoxadi zole (DBD-PZ) and N-hydrazinoformylmethyl-N-methylamino-4,4- N,N-dimethylaminosulphonyl-2,1,3-benzoxadiazole (DBD-CO-Hz) by high-performance liquid chromatography (HPLC) and electrospray ionization mass spectrometry (ESI-MS) were examined. The diastereomeric derivatization with (S)-DBD-Apy or (R)-NBD-Apy and the separation on the reversed phase column afforded the high sensitivity. The separation on chiral stationary phase after non-chiral derivatization with DBD-PZ or DBD-CO-Hz provided less sensitivity. The signal-to-noise ratio of (S)-DBD-Apy-(S)-ketoprofen of 200:1 was observed for 12.5 picomole (pmol) injection and selected ion monitoring (SIM) of the quasi-molecular ion after splitting 1:7 before entering into the electrospray ion sources. As a result, the usefulness of these reagents for MS detection has been demonstrated.