小泡
石英晶体微天平
吸附
化学
解吸
二氧化硅
脂质双层
磷脂
动力学
朗缪尔吸附模型
朗缪尔
单层
磷脂酰胆碱
化学工程
分析化学(期刊)
膜
色谱法
有机化学
生物化学
量子力学
物理
工程类
作者
Iad Alhallak,Peter J. N. Kett
摘要
Supported Lipid Bilayers (SLBs) are model biological membranes that have been developed to study the interactions between biomolecules in a cell membrane. Though forming SLBs is relatively easy, their formation mechanism remains a topic of debate. When buffered solutions containing phosphatidylcholine vesicles are flowed over a silicon dioxide (SiO2) surface they adsorb intact to the surface to form a Supported Vesicle Layer (SVL) if the pH of the buffer is above 9. We have run experiments with buffers with a pH at or above 9 to study the kinetics of the adsorption of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) vesicles to an SiO2 surface, which is the first step in the formation of an SLB. We used a quartz crystal microbalance (QCM) to monitor the real-time changes in the mass of the SVL as it formed from solutions with different lipid concentrations. Increases in the maximum frequency change with increasing lipid concentration indicated that both adsorption and desorption of DOPC vesicles were occurring, and that an equilibrium was established between the DOPC vesicles in the SVL and in the bulk solution. From the data acquired we were able to determine that the equilibrium constant for the adsorption and desorption of DOPC vesicles was 18 ± 1. The data was fitted to a Langmuir adsorption model from which the rate constants for the adsorption and desorption of DOPC vesicles were determined to be ka = (0.0107 ± 0.0004) mL mg-1 s-1 and kd = (5.8 ± 0.3) × 10-4 s-1. The best fit to the experimental data was achieved if a parameter (α = (0.035 ± 0.003) s-1) was used to account for the time taken for the lipid concentration to reach its steady state value in the flow cell used in the experiments.
科研通智能强力驱动
Strongly Powered by AbleSci AI