title: Online kinetic studies on intermediates of laccase-catalyzed reaction in reversed micelle.
abstract: Using water/AOT/n-octane reversed micelle as the medium, the optical signal of the reactive intermediate of laccase-catalyzed oxidation of o-phenylenediamine, which was indetectable in aqueous solutions, was successfully captured. Thus online kinetic studies of the intermediate were accomplished. Two-way kinetic spectral data were acquired with stopped-flow technique. By resolving the data with global analysis software, both the kinetic curves and the absorption spectra of the components involved in the reaction process were simultaneously obtained. The whole reaction in the reversed micelle was proved to be composed of two successive steps, an enzymatic generation of the intermediate and a following nonenzymatic decay of the intermediate. A consecutive first-order kinetic model of the whole reaction was confirmed. The influences of microenvironmental factors of the medium (such as the pH value of the water pool and the water/AOT ratio) on the detection of the intermediate were also investigated.
authors.affiliation: Department of Chemistry, Wuhan University, Wuhan 430072, China. zhhliu.whu@163.com
authors.forename: Zhi-Hong
authors.initials: ZH
authors.lastname: Liu
authors.forename: Mei
authors.initials: M
authors.lastname: Shao
authors.forename: Ru-Xiu
authors.initials: RX
authors.lastname: Cai
authors.forename: Ping
authors.initials: P
authors.lastname: Shen
mesh_terms: D002384:Catalysis; D004789:Enzyme Activation; D004795:Enzyme Stability; D007700:Kinetics; D042845:Laccase / Q000737:chemistry*; D008823:Micelles; D009795:Octanes / Q000737:chemistry; D010084:Oxidation-Reduction; D010655:Phenylenediamines / Q000737:chemistry; D012997:Solvents / Q000737:chemistry*; D013053:Spectrophotometry; D013386:Succinates / Q000737:chemistry; D013501:Surface-Active Agents / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: C512554:1,4-bis(2-ethylhexyl) sodium sulfosuccinate; D008823:Micelles; D009795:Octanes; D010655:Phenylenediamines; D012997:Solvents; D013386:Succinates; D013501:Surface-Active Agents; D014867:Water; C034193:1,2-diaminobenzene; D042845:Laccase; C026728:octane