Design of 3-(4-carboxybenzoyl)-2-quinolinecarboxaldehyde as a reagent for ultrasensitive determination of primary amines by capillary electrophoresis using laser fluorescence detection.

Amino acids and peptides, from both standard solutions and biological samples, were successfully reacted with 3-(4-carboxybenzoyl)-2-quinolinecarboxaldehyde, at low concentration, to form highly fluorescent isoindole derivatives. The formed mixtures are effectively separated by high-performance capillary electrophoresis and their constituents detected by their laser-induced fluorescence signals. The minimum detectable quantities in the low attomole (10(-18) mol) range are encountered.