title: [Interaction between protein and ciprofloxacin].
abstract: OBJECTIVE
  To study the interaction between ciprofloxacin and BSA in physiological condition by fluorescence spectroscopy.
  
  
  METHODS
  The affection of drug to the protein conformation was investigated. The binding constant between drug and BSA from a double reciprocal Lineweaver-Burk plot was determined and the main sort of binding force was found according to the thermodynamic parameters.
  
  
  RESULTS
  The binding constants between BSA and ciprofloxacin at 26 degrees C and 45 degrees C are about 10(4). At 26 degrees C, the thermodynamic parameters of reaction between BSA and ciprofloxacin are delta H = -49.13 kJ.mol-1, delta G = -26.45 kJ.mol-1, delta S = -75 kJ.mol-1. The maximum wavelength of the synchronous fluorescence spectra of BSA moved from 279 nm to 289 nm with the increasing of the amount of ciprofloxacin.
  
  
  CONCLUSIONS
  There exists fluorescence energy transfer between BSA and ciprofloxacin. The main sort of binding force between BSA and ciprofloxacin is Van der Waals' interaction. Ciprofloxacin can be deposited and be transported by serum protein in vivo. Ciprofloxacin affects the protein conformation.
authors.affiliation: Deparment of Analytical Chemistry, China Pharmaceutical University, Nanjing 210009, China.
authors.forename: H
authors.initials: H
authors.lastname: He
authors.forename: J S
authors.initials: JS
authors.lastname: Yu
authors.forename: S P
authors.initials: SP
authors.lastname: Xu
authors.forename: D S
authors.initials: DS
authors.lastname: Zhou
authors.forename: Y
authors.initials: Y
authors.lastname: Liu
mesh_terms: D000890:Anti-Infective Agents / Q000378:metabolism / Q000494:pharmacology; D002939:Ciprofloxacin / Q000378:metabolism / Q000494:pharmacology*; D011487:Protein Conformation / Q000187:drug effects; D012710:Serum Albumin, Bovine / Q000378:metabolism*; D013050:Spectrometry, Fluorescence
chemical_list: D000890:Anti-Infective Agents; D012710:Serum Albumin, Bovine; D002939:Ciprofloxacin