title: Magnetic core/shell Fe3O4/Au nanoparticles for studies of quinolones binding to protein by fluorescence spectroscopy.
abstract: Magnetic core/shell Fe3O4/Au nanoparticles were used in the determination of drug binding to bovine serum albumin (BSA) using a fluorescence spectroscopic method. The binding constants and number of binding sites for protein with drugs were calculated using the Scatchard equation. Because of their superparamagnetic and biocompatible characteristics, magnetic core/shell Fe3O4/Au nanoparticles served as carrier proteins for fixing proteins. After binding of the protein to a drug, the magnetic core/shell Fe3O4/Au nanoparticles-protein-drug complex was separated from the free drug using an applied magnetic field. The free drug concentration was obtained directly by fluorescence spectrometry and the proteins did not influence the drug determination. So, the achieved number of binding sites should be reliable. The binding constant and site number for ciprofloxacin (CPFX) binding to BSA were 2.055 × 10(5) L/mol and 31.7, and the corresponding values for norfloxacin (NOR) binding to BSA were 1.383 × 10(5) L/mol and 38.8. Based on the achieved results, a suitable method was proposed for the determination of binding constants and the site number for molecular interactions. The method was especially suitable for studies on the interactions of serum albumin with the active ingredients of Chinese medicine.
authors.affiliation: College of Chemistry, Jilin University, Changchun, People's Republic of China.
authors.forename: Rui
authors.initials: R
authors.lastname: Jin
authors.affiliation: College of Chemistry, Jilin University, Changchun, People's Republic of China.
authors.forename: Daqian
authors.initials: D
authors.lastname: Song
authors.affiliation: College of Chemistry, Jilin University, Changchun, People's Republic of China.
authors.forename: Huixia
authors.initials: H
authors.lastname: Xiong
authors.affiliation: College of Chemistry, Jilin University, Changchun, People's Republic of China.
authors.forename: Lisha
authors.initials: L
authors.lastname: Ai
authors.affiliation: College of Chemistry, Jilin University, Changchun, People's Republic of China.
authors.forename: Pinyi
authors.initials: P
authors.lastname: Ma
authors.affiliation: College of Chemistry, Jilin University, Changchun, People's Republic of China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Sun
mesh_terms: D000818:Animals; D001665:Binding Sites; D002417:Cattle; D006046:Gold / Q000737:chemistry*; D060328:Magnetic Phenomena; D053768:Metal Nanoparticles / Q000737:chemistry*; D015363:Quinolones / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D013050:Spectrometry, Fluorescence
chemical_list: D015363:Quinolones; D012710:Serum Albumin, Bovine; D006046:Gold
keywords: Fe3O4/Au nanoparticles; bovine serum albumin; fluorescence spectrometry