title: Design and synthesis of a hydrophilic fluorescent derivatization reagent for carboxylic acids, 4-N-(4-N-aminoethyl)piperazino-7-nitro-2,1,3-benzoxadiazole (NBD-PZ-NH2), and its application to capillary electrophoresis with laser-induced fluorescence detection.
abstract: A hydrophilic fluorescent derivatization reagent for fatty acids, 4-N-(4-N-aminoethyl)piperazino-7-nitro-2,1,3-benzoxadiazole (NBD-PZ-NH(2)), was designed and synthesized. NBD-PZ-NH(2) possesses not only a fluorophore and a reacting group but also a positive charge group and, thus, was hydrophilic and suitable for application to capillary electrophoresis. NBD-PZ-NH(2) reacted with fatty acids in the presence of triphenylphosphine (TPP) and 2,2'-dipyridyl disulfide (DPDS) at room temperature within 10 min. The derivatives were strongly fluoresced and were positively charged at pH below 3. The derivatives of C4-C20 fatty acids were separated within 10 min in 50% acetonitrile in water containing 30 mM ammonium acetate and 1.0 M acetic acid by capillary electrophoresis with laser-induced fluorescence (CE-LIF) detection. The detection limits attained were 6.5 nM (signal-to-noise ratio of 3). It is proposed that NBD-PZ-NH(2) is a prominent derivatization reagent for fatty acids which is suitable for CE-LIF application.
authors.affiliation: Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Japan. santa@mol.f.u-tokyo.ac.jp
authors.forename: Tomofumi
authors.initials: T
authors.lastname: Santa
authors.forename: Daisuke
authors.initials: D
authors.lastname: Matsumura
authors.forename: ChengZhi
authors.initials: C
authors.lastname: Huang
authors.forename: Chieko
authors.initials: C
authors.lastname: Kitada
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Imai
mesh_terms: D002264:Carboxylic Acids / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D019075:Electrophoresis, Capillary / Q000379:methods*; D005456:Fluorescent Dyes / Q000737:chemistry*; D007834:Lasers; D013058:Mass Spectrometry; D010069:Oxadiazoles / Q000737:chemistry*; D010879:Piperazines / Q000737:chemistry*; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000379:methods*
chemical_list: C432126:4-nitro-7-piperazino-2,1,3-benzoxadiazole; D002264:Carboxylic Acids; D005456:Fluorescent Dyes; D010069:Oxadiazoles; D010879:Piperazines