Collaborative Research: Quantitative Analysis of Liposome Deformation at Nanoscale Using Resistive Pulse Sensing in Solid State Nanopores

合作研究：利用固态纳米孔中的电阻脉冲传感对纳米尺度脂质体变形进行定量分析

基本信息

批准号：
1740011
负责人：
Petia Vlahovska
金额：
$ 20万
依托单位：
Northwestern University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2017
资助国家：
美国
起止时间：
2017-07-01 至 2020-08-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1740011&HistoricalAwards=false
关键词：
Collaborative Research Quantitative Analysis Liposome

项目摘要

Tiny lipid sacs, called liposomes, play a crucial role in living cells as means to store and transport material in and out of the cell. The key task of liposomes (storage and delivery to targets) requires them to be flexible enough to merge with target membranes in order to deliver their cargos, and yet to have sufficient structural stability to maintain integrity without rupturing and losing the stored material in the naturally dynamic biological environments. Therefore, understanding the mechanics of liposomes is of great interest to both fundamental and applied scientists who are developing artificial, biomimetic liposomes as targeted drug/gene delivery systems for better therapeutics. A major challenge however, is the lack of efficient engineering tools to probe the mechanical flexibility of the sub-cellular, nanoscale liposomes. The research addresses this need by developing a novel method based on nanopore technology that uses electric fields to deform liposomes and electrical measurements to characterize their shape. The overall goal is to characterize the mechanical flexibility of nano-liposomes with the ultimate goal to establish a method to study mechanical properties of nanoscale objects such as viruses and other biological samples at cellular/molecular level.This project will advance the engineering tools for mechanical characterization of soft biological materials at the micro/nanoscale. The technology uses nanopore resistive pulse sensing to detect membrane deformation. As liposomes translocate through a nanopore, they experience strong electric stresses and physical confinement, which cause deformation. In this project, liposome shapes will be inferred from ionic current blockade, i.e., the sharp change (pulse) in ohmic resistance when a liposome is present in the pore. A theoretical model for liposome deformation in the nanopore will be developed to yield membrane mechanical properties. The method will enable both high-throughput and single-particle resolution because (1) thousands of liposomes pass through the nanopore and a resistive pulse will be recorded for each individual one, and (2) thousands of measurements on a single liposome can be made by alternating the applied electric field direction to drive back-and-forth translocation. In broader terms, this method will enable studying mechanobiology at novel unprecedented scales, which is single-virus and single-particle level.

小脂质囊（称为脂质体）在活细胞中起着至关重要的作用，作为将材料存储在细胞中和流出细胞中的手段。脂质体的关键任务（存储和交付到目标）要求它们具有足够的灵活性，可以与靶膜合并，以便传递其货物，并且还具有足够的结构稳定性，可以保持完整性，而不会破裂并在自然动态生物学环境中失去储存的材料。因此，了解脂质体的力学对于基本和应用科学家来说都是极大的兴趣，他们正在开发人工，仿生脂质体作为靶向药物/基因递送系统，用于更好的治疗疗法。然而，一个主要的挑战是缺乏有效的工程工具来探测亚细胞纳米级脂质体的机械灵活性。该研究通过开发一种基于纳米孔技术的新方法来满足这种需求，该方法使用电场来变形脂质体和电测量以表征其形状。总体目标是表征纳米脂质体的机械灵活性，其最终目标是建立一种研究纳米级对象的机械性能，例如病毒对象，例如病毒和其他生物样品，在细胞/分子水平上。该项目将推进Micro/Nansoccale中软性生物学机械表征的工程工具。该技术使用纳米电阻脉冲传感来检测膜变形。当脂质体通过纳米孔转移时，它们会经历强烈的电压力和物理限制，这会导致变形。在这个项目中，将从离子电流阻断中推断出脂质体形状，即当毛孔中存在脂质体时，欧姆电阻的急剧变化（脉冲）。将开发纳米孔中脂质体变形的理论模型，以产生膜机械性能。该方法将同时实现高通量和单粒子分辨率，因为（1）成千上万的脂质体通过纳米孔，并且每个单独的脂质体都会记录一个电阻脉冲，并且（2）可以通过使施加的电场方向交流的单个脂质体上的数千个测量值，以驱动反向转移。从更广泛的角度来看，这种方法将使在新型前所未有的量表上研究机械生物学，这是单病毒和单粒子水平。