DTU Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, Orsteds plads, DK-2800 Kgs. Lyngby, Denmark.
Langmuir. 2010 Apr 20;26(8):5421-7. doi: 10.1021/la903877f.
We present an experimental study of vesicle fusion using light and neutron scattering to monitor fusion events. Vesicles are reproducibly formed with an extrusion procedure using an single amphiphile triethylene glycol mono-n-decyl ether in water. They show long-term stability for temperatures around 20 degrees C, but at temperatures above 26 degrees C we observe an increase in the scattered intensity due to fusion. The system is unusually well suited for the study of basic mechanisms of vesicle fusion. The vesicles are flexible with a bending rigidity of only a few k(B)T. The monolayer spontaneous curvature, H(0), depends strongly on temperature in a known way and is thus tunable. For temperatures where H(0) > 0 vesicles are long-term stable, while in the range H(0) < 0 the fusion rate increases the more negative the spontaneous curvature. Through a quantitative analysis of the fusion rate we arrive at a barrier to fusion changing from 15 k(B)T at T = 26 degrees C to 10 k(B)T at T = 35 degrees C. These results are compatible with the theoretical predictions using the stalk model of vesicle fusion.
我们使用光和中子散射来监测融合事件，展示了一种使用单分子两亲物三甘醇单壬醚在水中进行囊泡融合的实验研究。在接近 20°C 的温度下，囊泡具有长期稳定性，但在 26°C 以上的温度下，由于融合，我们观察到散射强度增加。该系统非常适合研究囊泡融合的基本机制。囊泡具有柔韧性，弯曲刚度仅为几个 kBT。单层自发曲率 H(0) 随温度以已知方式强烈依赖，因此可调节。在 H(0) > 0 的温度下，囊泡具有长期稳定性，而在 H(0) < 0 的范围内，自发曲率越负，融合速率越高。通过对融合速率的定量分析，我们得出融合势垒从 T = 26°C 时的 15 kBT 变为 T = 35°C 时的 10 kBT。这些结果与使用囊泡融合的茎突模型的理论预测是一致的。
