Fluorescent derivatization of arginine- and carbonyl-containing analytes for analysis by capillary electrophoresis with laser-induced fluorescence detection

Microcystin-LR was shown to be successfully derivatized via an arginine-labelling reaction with the fluorescent tags 5-TAMRA-SE and 5-BMF through analysis by MALDI-MS, ESI-MS and CZE-LIF. A microcystin-LR fluorescent flow displacement immunoassay was constructed and the resulting calibration curve had a correlation coefficient of +0.9922 with a limit of detection of 10-10 M.;A carbonyl-labelling reaction was developed and found to be most efficient, through analysis by ESI-MS and CZE-LIF, when performed in the absence of 18-Crown-6 and/or TED and when two molar equivalents of 5-BMF were reacted. The reactant limitation was 10-8 moles and the reaction time optimizations were not conclusive.;The optimized carbonyl-labelling reaction was then applied to a series of FFAs. MECK-LIF analysis showed product peaks for every acid in the series with migration times of 6.3--9.8 minutes with LODs ranging from 0.1--2.2 nM. ESI-MS analysis confirmed that each carbonyl-labelling reaction performed was successful.