title: Spectroscopic studies on the interactions between imidazolium chloride ionic liquids and bovine serum albumin.
abstract: The binding of three imidazolium chloride ionic liquids (ILs) with bovine serum albumin (BSA) were investigated by UV absorption spectra, fluorescence spectra and synchronous fluorescence spectra. The results showed that the UV absorption of the BSA was red-shift, and intensity of UV absorption declined with the increase in concentration of ILs. According to fluorescence spectra, fluorescence quenching of the BSA was happened with ILs added, and the main reason is static quenching. The study of synchronous fluorescence spectra indicated that ILs interacted with tryptophan (Trp) and tyrosine (Tyr) residues, changed the structure and the internal hydrophobic conformation of BSA. The binding constant K and the numbers of binding sites n were obtained by Stern-Volmer equation. For [Bmim]Cl, K=16.12 L mol(-1), n was 0.64; for [Hmim]Cl, K=31.48 L mol(-1), n was 0.70; for [Omim]Cl, K=355.22 L mol(-1), n was 0.99. The binding strength of ILs with BSA is expected to show the trend with the length of carbon chain, [Bmim]Cl<[Hmim]Cl<[Omim]Cl.
authors.affiliation: College of Environmental Science and Engineering, Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, Zhejiang Gongshang University, Hangzhou Zhejiang 310012, China.
authors.forename: Ruonan
authors.initials: R
authors.lastname: Huang
authors.forename: Shuxian
authors.initials: S
authors.lastname: Zhang
authors.forename: Lili
authors.initials: L
authors.lastname: Pan
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.forename: Fu
authors.initials: F
authors.lastname: Liu
authors.forename: Huijun
authors.initials: H
authors.lastname: Liu
mesh_terms: D000818:Animals; D001665:Binding Sites; D002417:Cattle; D007093:Imidazoles / Q000737:chemistry / Q000378:metabolism*; D052578:Ionic Liquids / Q000737:chemistry / Q000378:metabolism*; D007700:Kinetics; D012710:Serum Albumin, Bovine / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet
chemical_list: D007093:Imidazoles; D052578:Ionic Liquids; D012710:Serum Albumin, Bovine; C029899:imidazole