title: Synthesis of three novel anionic gemini surfactants and comparative studies of their assemble behavior in the presence of bovine serum albumin.
abstract: Three novel anionic sulfonate gemini surfactants, sodium 4,4'-(10,19-dioxo-9,11,18,20-tetraazaoctacosane-9,20-diyl) dibenzenesulfonate (Surfactant I), sodium 4,4'-(12,21-dioxo-11,13,20,22-tetraazadotriacontane-11,22-diyl) dibenzenesulfonate (Surfactant II), and sodium 4,4'-(14,23-dioxo-13,15,22,24-tetraazahezatriacontane-13,24-diyl) dibenzenesulfonate (Surfactant III), with different lengths of hydrophobic tail have been synthesized, and their assembly behavior in the presence of bovine serum albumin (BSA) has been studied using spectral methods and molecular modeling methods at physiological pH and 298 K. Critical micelle concentrations (CMCs) of the three surfactants have been determined by surface tension measurements. Despite the obvious decrease of CMC with the increase of tail length, fluorescence spectra have shown much closer CAC in the presence of BSA. Surfactant II shows the highest CAC of 3.19 × 10(-5) mol L(-1) compared with the other two. The polarity of the microenvironment in BSA-surfactant systems has been investigated using pyrene as the probe. In addition, far-UV CD spectra studied the change of the secondary structure content of BSA caused by the three surfactants. The features of the assembly behavior were discussed by three concentration regions. Surfactant II could unfold the protein much more efficiently than the other two surfactants at low concentration, but at high concentration, the change of the secondary structure and the formation of hydrophobic microenvironment show a direct relationship to the length of the hydrophobic tail with the increase of the surfactant concentration.
authors.affiliation: State Key Laboratory of Virology & Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, PR China.
authors.forename: Yu-Shu
authors.initials: YS
authors.lastname: Ge
authors.forename: Shu-Xin
authors.initials: SX
authors.lastname: Tai
authors.forename: Zi-Qiang
authors.initials: ZQ
authors.lastname: Xu
authors.forename: Lu
authors.initials: L
authors.lastname: Lai
authors.forename: Fang-Fang
authors.initials: FF
authors.lastname: Tian
authors.forename: Dong-Wei
authors.initials: DW
authors.lastname: Li
authors.forename: Feng-Lei
authors.initials: FL
authors.lastname: Jiang
authors.forename: Yi
authors.initials: Y
authors.lastname: Liu
authors.forename: Zhi-Nong
authors.initials: ZN
authors.lastname: Gao
mesh_terms: D000818:Animals; D002417:Cattle; D060326:Chemistry Techniques, Synthetic; D008958:Models, Molecular; D017433:Protein Structure, Secondary; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013451:Sulfonic Acids / Q000138:chemical synthesis* / Q000737:chemistry* / Q000493:pharmacokinetics / Q000494:pharmacology; D013501:Surface-Active Agents / Q000138:chemical synthesis* / Q000737:chemistry* / Q000493:pharmacokinetics / Q000494:pharmacology
chemical_list: D013451:Sulfonic Acids; D013501:Surface-Active Agents; D012710:Serum Albumin, Bovine