Development of 7-(N,N-dimethylaminosulfonyl)-5-N-(4-N-aminoethyl)piperazino-2,1,3-benzoxadiazole as a water-soluble fluorogenic reagent for the sensitive liquid chromatographic determination of saturated carboxylic acids.

摘要: A reversed-phase high-performance liquid chromatographic (HPLC) method for the femtomole determination of nine saturated carboxylic acids, n-butyric (C4), n-hexanoic (C6), n-caprylic (C8), n-decanoic (C10), lauric (C12), n-tetradecanoic (C14), palmitic (C16), stearic (C18) and arachidic (C20), based on condensation reaction these acids with a newly synthesized water-soluble benzofurazan fluorescent reagent, 7-(N,N-dimethylaminosulfonyl)-4-N-(4-N-aminoethyl)piperazino-2,1,3-benzoxadiazole (DBD-PZ-NH2), was developed. The derivatization proceeds 1-[3-(dimethylamino)propyl]-3-ethylcarbodiimide (EDC) in presence catalyst 4-(dimethylamino)pyridine (DMAP). model derivative reagent acid (C8) fluorescence excitation/emission characterization. Depending solvents, including water, methanol, acetonitrile, 1,4-dioxane or N,N-dimethyformamide (DMF), C8 has emission quantum yield (φ) ranging from 0.01 to 0.20 region 545 580 nm. An exponential increase φ observed increasing acetonitrile content. calculated detection limits (signal-to-noise ratio = 3∶1) proposed above were 9.1, 4.0, 2.5, 2.2, 2.0, 1.8, 1.2, 1.0 1.3 fmol, respectively. Biological samples including Intralipos 20% rat plasma analysed satisfactorily.