A polymeric anhydride containing o-acetylsalicyl as the labelling moiety was utilized as a derivatization reagent in conjunction with high-performance liquid chromatography for primary and secondary amines. The derivatization reactions were performed off-line, before the chromatographic separation. Standards were prepared, characterized by melting point, UV, IR, NMR, mass spectrometry, and elemental analysis, and these were then used as external standards to determine the percent reaction. The derivatives are easily chromatographed on a reversed-phase high-performance liquid chromatographic system and can be monitored by a UV detector at 196 nm, or an electrochemical detector in the oxidative mode, with or without post-column photolysis. No pH suppression of the eluent was needed. The minimum detection limits of underivatized and derivatized amines were determined. There was a decrease of 3 to 4 orders of magnitude in minimum detection limits as a result of these off-line derivatizations. The minimum amount of amine that can be detected through derivatization is also reported.