| Biomembranes play very important roles in life process, and closely relate to many life phenomena. However, in-situ observation and investigation of these membranes are very difficult, owing to the complexity of the components, the structures, and the functions of biomembranes. Therefore, the simulation of biomembranes can be adapted as a very promising analytical tool to understand the property of biomembranes. In this thesis, based on the home-made SPR instrument, the study of solid-supported bilayer membranes was carried out using the combined system of SPR and electrochemistry measurements. The brief parts of this work are as follows:1. Study on the preparation of solid-supported bilayer membranesTwo kinds of solid-supported bilayer membranes were prepared by liposomes adsorption, which were stable and solvent free. The formation of the phospholipid layers on hydrophilic and hydrophobic surfaces was investigated using the combined techniques of SPR and electrochemistry. The results showed that the value of SPR wavelength shift induced by the assembly of phospholipids on hydrophilic surface was almost twice as that on hydrophobic surface, which was related with the number of lipid layers on the two different surfaces. Meanwhile, the capacity current was reduced by the adsorption of phospholipids on hydrophobic surface, indicating the blocking behavior of the lipid layer for the penetration of ions. However, the capacity current was not reduced by the adsorption of phospholipids on hydrophilic surface, and it might be due to the pin-hole defects in lipid membranes. The preparation of solid-supported bilayer membranes offered the groundwork and precondition for the investigation of biomembranes.2. The effects of surfactants and organic small molecules on solid-supported bilayer membranesBaesed on the formation of the phospholipid layers on hydrophilic and hydrophobic surfaces in the first part, the effect of surfactants and organic small molecules on solid-supported bilayer membranes was investigated by SPR and impedance measurements. The results showed that the lipid membranes usually remained intact unless in high concentration of organic small molecules, but were destroyed immediately in a very low concentration of surfactants, owing to the different mechanism of destroying lipid membranes. High concentration of ethanol ordimethylsulfoxide enhanced the solubility of phospholipids and made them desorb from solid surface, while surfactants inserted lipid membranes to form micelles with phospholipids and the micelles leave the solid surface and enter the solution. At the same time, a few distinctions were observed in the resistance to chemicals destruction between Au/alkanethiol/phospholipid membrane and Au/hydroxythiol/phospholipid membrane, due to the different funds for supporting phospholipid membranes. The investigation about the effect of chemicals on lipid membranes not only afforded the guidance for designing sensors based on membranes, but also had important sense for the study of environmental science and biotoxicology.3. Research of the interaction between nystatin and solid-supported bilayer membranesTo study the interaction between drugs and mimetic biomembranes with SPR was not only able to validate its mechanism, but also able to select and judge drugs with speed, simplicity and sensitivity in contrast to common techniques. There was a debate that whether sterol played a crucial role in the interaction between polyene antibiotics and biomembranes all the times. Aiming at this problem, we used SPR and impedance to investigate the interaction between nystatin and two kinds of solid-supported bilayer membranes. The results showed that nystatin did not interact with pure phospholipid membranes in monomer state, but interacted with the membranes to form ion channels in aggregation state. It was concluded that the state of nystatin in solution was very important for the interaction between nystatin and pure phospholipid membranes.
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