title: Selective determination of quinones by high-performance liquid chromatography with on-line post column ultraviolet irradiation and peroxyoxalate chemiluminescence detection.
abstract: A new HPLC method was developed for the simultaneous determination of quinones with peroxyoxalate chemiluminescence (PO-CL) detection following on-line UV irradiation. Quinones [i.e., 1,2-naphthoquinone, 1,4-naphthoquinone, 9,10-anthraquinone, 9,10-phenanthrenequinone] were UV irradiated (254 nm, 15 W) to generate hydrogen peroxide and a fluorescent product that were determined via PO-CL detection. Generation of hydrogen peroxide from quinones with on-line UV irradiation was confirmed using flow injection analysis (FIA) system whereby incorporating an enzyme column reactor immobilized with catalase. Moreover, the structure of the produced fluorophore was confirmed using LC-MS, IR, and (1)H NMR. Afterwards, the conditions for UV irradiation and PO-CL detection were optimized. The separation of four quinones by HPLC was accomplished isocratically on an ODS column within 25 min. The detection limits (signal-to-noise ratio=3) were 6.0 pmol/injection for 1,2-naphthoquinone, 4.4 pmol/injection for 1,4-naphthoquinone, 0.2 pmol/injection for 9,10-anthraquinone, and 0.45 pmol/injection for 9,10-phenanthrenequinone.
authors.affiliation: Graduate School of Biomedical Sciences, Course of Pharmaceutical Sciences, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan.
authors.forename: Sameh
authors.initials: S
authors.lastname: Ahmed
authors.forename: Shuu
authors.initials: S
authors.lastname: Fujii
authors.forename: Naoya
authors.initials: N
authors.lastname: Kishikawa
authors.forename: Yoshihito
authors.initials: Y
authors.lastname: Ohba
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Nakashima
authors.forename: Naotaka
authors.initials: N
authors.lastname: Kuroda
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods*; D008163:Luminescent Measurements / Q000295:instrumentation / Q000379:methods*; D008956:Models, Chemical; D010070:Oxalates / Q000737:chemistry*; D011809:Quinones / Q000032:analysis* / Q000737:chemistry; D015203:Reproducibility of Results; D014466:Ultraviolet Rays
chemical_list: D010070:Oxalates; D011809:Quinones; C044622:peroxyoxalate