title: In vitro kinetic evaluation of the free radical scavenging ability of propofol.
abstract: BACKGROUND
  Propofol is a widely used, short-acting, and intravenously administered hypnotic agent with notable antioxidant and free radical scavenging activities. However, there are relatively few kinetic studies on the free radical scavenging ability of propofol. The goal of this study is to evaluate the kinetics of propofol scavenging 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical (ABTS(·+)).
  
  
  METHODS
  The stock solution of ABTS(·+) was prepared by incubating 7 mM ABTS with 2.8 mM potassium persulfate in deionized water, and then diluted with 5 mM phosphate-buffered saline (pH 7.2) to get a working solution (36 μM ABTS(·+) and 18 μM ABTS). The reaction was monitored by measuring specific absorbance changes of ABTS and ABTS(·+) after adding 4 μM propofol (final concentration) to the working solution. The propofol-ABTS(·+) reaction products were analyzed by high-performance liquid chromatography and liquid chromatography mass spectrometry/mass spectrometry.
  
  
  RESULTS
  Wave scanning and kinetic evaluation demonstrated that the ABTS(·+) scavenging process of propofol is relatively fast. The ABTS(·+) consumption rate by propofol is greater than the rate of ABTS formation. The degradation products of reaction between propofol and ABTS(·+) were mainly ABTS-propofol, a part of the ABTS molecule, and a combination of propofol with a part of the ABTS molecule.
  
  
  CONCLUSIONS
  Propofol scavenges ABTS(·+) with a fast and stable kinetic feature in vitro, which is useful and important for understanding propofol's antioxidant properties. The kinetic process of the free radical scavenging activity of propofol may also play a role in dynamic protection in the body.
authors.affiliation: Beijing Institute of Radiation Medicine, State Key Laboratory of Proteomics, Cognitive and Mental Health Research Center, Beijing, China.
authors.forename: Weiguang
authors.initials: W
authors.lastname: Li
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.forename: Yanru
authors.initials: Y
authors.lastname: Liu
authors.forename: Feng
authors.initials: F
authors.lastname: Yue
authors.forename: Yiming
authors.initials: Y
authors.lastname: Lu
authors.forename: Huanrong
authors.initials: H
authors.lastname: Qiu
authors.forename: Dawen
authors.initials: D
authors.lastname: Gao
authors.forename: Yan
authors.initials: Y
authors.lastname: Gao
authors.forename: Yonghong
authors.initials: Y
authors.lastname: Wu
authors.forename: Zhaoyan
authors.initials: Z
authors.lastname: Wang
authors.forename: Rongqing
authors.initials: R
authors.lastname: Huang
authors.forename: Chenggang
authors.initials: C
authors.lastname: Zhang
mesh_terms: D018686:Anesthetics, Intravenous / Q000737:chemistry*; D052160:Benzothiazoles / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D004583:Electrons; D016166:Free Radical Scavengers; D005609:Free Radicals / Q000737:chemistry; D007700:Kinetics; D015742:Propofol / Q000737:chemistry*; D012996:Solutions; D013057:Spectrum Analysis; D013451:Sulfonic Acids / Q000737:chemistry
chemical_list: D018686:Anesthetics, Intravenous; D052160:Benzothiazoles; D016166:Free Radical Scavengers; D005609:Free Radicals; D012996:Solutions; D013451:Sulfonic Acids; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; D015742:Propofol