Counting and Dynamic Studies of the Small Unilamellar Phospholipid Vesicle Trans location with Single Conical Glass Nanopores
Counting and Dynamic Studies of the Small Unilamellar Phospholipid Vesicle Trans location with Single Conical Glass Nanopores
复制标题
单层圆锥玻璃纳米孔小单层磷脂囊泡转运的计数和动态研究
DOI：
10.1021/ac5029243
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发表时间：
2015-01-06
影响因子：
7.4
通讯作者：
Jin, Yongdong
中科院分区：
文献类型：
--
作者：
Chen, Lizhen;He, Haili;Jin, Yongdong
磷脂囊泡是一种普遍存在的细胞器，具有重要的物质转运和信息传递功能，在生物医学领域有着广泛的应用前景。虽然磷脂囊泡，特别是小单层磷脂囊泡（SUV）的跨膜易位（经由纳米孔）被认为对于这些过程和应用非常重要，但是细节和动力学仍然不是很清楚。在本文中，我们使用单个锥形玻璃纳米孔作为模型平台，系统地研究SUV（直径类似于50-60 nm）通过孔口直径范围类似于14至72 nm的小纳米孔的易位动力学。清楚地观察到单个SUV一个接一个地通过纳米孔的动态移位，并通过在负施加电压下离子电流阻断信号中周期性振荡的发生来分析。SUV的易位行为，在离子电流阻断信号的幅度和持续时间方面，变化并且可以通过改变纳米孔尺寸、溶液pH、囊泡浓度、施加电压和纳米孔的内表面电荷性质来调制。SUV通过类似于72 nm的纳米孔的易位速率通常在几秒的时间尺度上（每个SUV易位事件），并且发现与SUV的浓度成非线性比例。此外，电泳力已被验证为驱动SUV通过纳米孔的主要力，因为SUV移位的电流阻断频率与范围为-0.6至-1 V的所施加偏压之间存在接近线性的关系。这些发现提供了对SUV与纳米孔的移位和相互作用的基本见解，并且所报道的纳米孔平台可能在单细胞和单囊泡研究中发现潜在有用的生物应用。
Phospholipid vesicles are ubiquitous cellular organelles that perform vital functions including materials transport and information transmission and have found promising biomedical applications. Although the transmembrane translocation (via nanopores) of phospholipid vesicles, especially small unilamellar phospholipid vesicles (SUVs), is recognized to be very important for these processes and applications, the details and dynamics remain not very clear. Herein, we use single conical glass nanopores as a model platform to systematically investigate the translocation dynamics of SUVs (similar to 50-60 nm in diameter) through small nanopores with orifice diameters ranging from similar to 14 to 72 nm. Dynamic translocation of individual SUVs one by one through the nanopores was clearly observed and was analyzed by the occurrence of periodic oscillation in ionic current blockage signal under a negatively applied voltage. Translocation behaviors of the SUVs, in terms of magnitude and duration of ionic current blockage signal, varied and can be modulated by changing nanopore size, solution pH, vesicle concentration, applied voltage, and inner surface charge properties of the nanopores. The translocation rate of the SUVs through an similar to 72 nm nanopore is typically on a time scale of a few seconds (per SUV translocation event) and found nonlinearly proportional to the concentration of the SUVs. Moreover, the electrophoretic force has been verified as a main force to drive the SUVs through the nanopore since there is a nearly linear relationship between the current blockage frequency of SUVs translocation and the applied bias potentials ranging from -0.6 to -1 V. The findings provide fundamental insights into the translocation and interactions of SUVs with nanopores, and the reported nanopore platform may find potential useful bioapplications in single-cell and single-vesicle studies.