十二烷基磺基甜菜碱与铂电极支撑的磷脂双层膜作用的电化学研究

Electrochemical Study on the Interaction of Dodecyl Sulfobetaine with a Supported Lipid Bilayer Membrane

以铂电极支撑的磷脂双层膜(Supported Bilayer Lipid Membrane,s-BLM)作为生物膜的模型,以Fe(CN)36-和Fe(CN)64-为探针分子,利用循环伏安法(CV)和交流阻抗谱(EIS)研究两性表面活性剂十二烷基磺基甜菜碱(Dodecyl Sulfobetaine,DSB)对s-BLM相互作用。结果显示,DSB可以嵌入到s-BLM的疏水区,容易使其表面分子的排列发生变化,产生缺陷或孔洞,探针分子Fe(CN)63-和Fe(CN)64-可以通过这些微孔接近电极,产生氧化还原响应。并且作用时间、DSB的浓度以及胆固醇的存在与否对二者的相互作用有直接影响。此外作用后的双层膜在0.1mol/LKCl溶液中能够自我修复,这表明DSB与s-BLM的相互作用是可逆的。

With supported bilayer lipid membrane （s-BLM） serving as a biomembrane model,and Fe（CN）3-6 and Fe（CN）4-6 serving as redox probes,the influence of dodecyl sulfobetaine（DSB） on s-BLMs was investigated by cyclic voltammetry （CV） and electrochemical impedance spectroscopy （EIS）. The following conclusions were obtained. There are some interactions between DSB and s-BLM,and DSB can be inserted into the hydrophobic areas of bilayer lipid membrane and decrease the orderliness of lecithin molecule arrangement and induce pores or defects on the bilayer lipid membrane. As a result,the redox probe can be close to electrode surface through these microporous,causing redox responses. The interaction between them depends on time,concentration and cholesterol. In addition,the defective s-BLM can be self-repaired in 0.1 mol/L KCl solution after interaction,which indicates that the inter-action is reversible. Moreover,a possible mechanism of the interaction has been proposed.