title: Determination of tryptophan and kynurenine in human plasma by liquid chromatography-electrochemical detection with multi-wall carbon nanotube-modified glassy carbon electrode.
abstract: A novel method was developed for the simultaneous determination of kynurenine and tryptophan by high-performance liquid chromatography with electrochemical detection at multi-wall carbon nanotube (MWCNT)-modified glassy carbon electrode. The separation and detection conditions were optimized. The typical HPLC experiments were conducted by using a reversed-phase ODS column with a mobile phase consisting of stock acetate buffer (pH 5)-methanol (4:1, v/v) using an isocratic elution at the flow rate of 1.0 mL/min. The obtained LODs for kynurenine and tryptophane were 0.5 and 0.4 µmol/L, respectively. The analytical method for human plasma samples was validated and confirmed by LC-UV and LC-MS. The recoveries were in the range of 84.8-110%, and the precision was lower than 5.9%.
authors.affiliation: Institute of Pharmaceutical Analysis, College of Pharmacy, Wuhan University, Wuhan 430072, China.
authors.forename: Lihong
authors.initials: L
authors.lastname: Liu
authors.forename: Ying
authors.initials: Y
authors.lastname: Chen
authors.forename: Yulin
authors.initials: Y
authors.lastname: Zhang
authors.forename: Fang
authors.initials: F
authors.lastname: Wang
authors.forename: Zilin
authors.initials: Z
authors.lastname: Chen
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation* / Q000379:methods; D055664:Electrochemical Techniques / Q000295:instrumentation* / Q000379:methods; D004566:Electrodes; D006801:Humans; D007737:Kynurenine / Q000097:blood*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D015203:Reproducibility of Results; D014364:Tryptophan / Q000097:blood*
chemical_list: D037742:Nanotubes, Carbon; D007737:Kynurenine; D014364:Tryptophan