title: A novel lophine-based fluorescence probe and its binding to human serum albumin.
abstract: The binding of a lophine-based fluorescence probe, 4-[4-(4-dimethylaminophenyl)-5-phenyl-1H-imidazol-2-yl]benzoic acid methyl ester (DAPIM) with human serum albumin (HSA) was investigated by fluorescence spectroscopy under physiological conditions. While DAPIM shows extreme low fluorescence in aqueous solution, DAPIM binding with HSA emits strong fluorescence at 510nm. The binding constant and binding number determined by Scatchard plot was 3.65×10(6)M(-1) and 1.07, respectively. Competitive binding between DAPIM and other ligands such as warfarin, valproic acid, diazepam and oleic acid, were also studied fluorometrically. The results indicated that the primary binding site of DAPIM to HSA is site II at subdomain IIIA. DAPIM can be a useful fluorescence probe for the characterization of drug-binding sites. In addition to the interaction study, because the fluorescence intensity of DAPIM increased in proportion to HSA concentration, its potential in HSA assay for serum sample was also evaluated.
authors.affiliation: Course of Pharmaceutical Sciences, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
authors.forename: Naoya
authors.initials: N
authors.lastname: Kishikawa
authors.forename: Kaname
authors.initials: K
authors.lastname: Ohyama
authors.forename: Akane
authors.initials: A
authors.lastname: Saiki
authors.forename: Aya
authors.initials: A
authors.lastname: Matsuo
authors.forename: Marwa Fathy Bakr
authors.initials: MF
authors.lastname: Ali
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Wada
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Nakashima
authors.forename: Naotaka
authors.initials: N
authors.lastname: Kuroda
mesh_terms: D001565:Benzoates / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D002942:Circular Dichroism; D005456:Fluorescent Dyes / Q000737:chemistry*; D006801:Humans; D007093:Imidazoles / Q000737:chemistry*; D015394:Molecular Structure; D011485:Protein Binding; D012709:Serum Albumin / Q000737:chemistry* / Q000378:metabolism
chemical_list: C584462:4-(4-(4-dimethylaminophenyl)-5-phenyl-1H-imidazol-2-yl)benzoic acid methyl ester; D001565:Benzoates; D005456:Fluorescent Dyes; D007093:Imidazoles; D012709:Serum Albumin; C107378:lophine