Dual-Sensitive Probe of 2-( Benzoacridin) ethyl-imidazole-1-carboxylate for Determination of Aliphatic Amine with Fluorescence and Online Atmospheric Pressure Chemical Ionization Mass Spectrometry Identification / 分析化学

ABSTRACT

With comparison of three different methods for the marking of amines compound, an optimal deri vatization method was selected.5-(2-Hydroxyethyl) benzoacridine (HBA) reacts with coupling agent N,N'-carbonyldiimidazole(CDI) to form an activated amide intermediate 2-(benzoacridin) ethyl-imidazole-1-carbox-ylate(BAEIC).BAEIC, which is dual-sensitive probe, reacts preferably with amino compounds at 80 ℃ in the presence of 4-dimethylaminopyridine(DMAP) catalyst in N,N-dimethylformamide(DMF) solvent to give the corresponding sensitively fluorescent derivatives with an excitation maximum at λ_(ex) of 280 nm and an emis sion maximum at λ_(em) of 510 nm.BAEIC-amine derivatives simultaneously exhibited high ionization potential with percent ionization (changing from 5.62% to 58.08% in aqueous acetonitrile and from 2.14% to 56.58% in aqueous methanol.Derivatives were not only sensitive to fluorescence but also to MS ionizable potential.The fluorescence detection limits(5/iV = 3) were 0.12-0.59 μg/L.The online APCI-MS detection limits were 1.9-14 μg/L(S/N=5).