Imaginary Magnetic Tweezers for Biophysical Force Measurements

用于生物物理力测量的假想磁力镊子

• 批准号: 0625480
• 负责人: Benjamin Yellen
• 金额: --
• 依托单位: Duke University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-10-01 至 2010-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0625480&HistoricalAwards=false
• 关键词: Imaginary; Magnetic; Tweezers; Biophysical; Force

0625480 YellenAbstractThe goal of this project is to develop massively parallel "imaginary" magnetic tweezers for quantifying intermolecular binding forces. In contrast to conventional magnetic tweezers, which employ large external magnets to apply field gradients and force on the colloidal particles, the proposed imaginary tweezer system is unique in that the force is produced by the particle's near-field interaction with its own image appearing in a planar substrate. The image repulsion is achieved by immersing the colloidal particle inside a solution of magnetic nanoparticles, known as ferrofluid. The primary goal of this proposal is to demonstrate the "proof of principle" of imaginary magnetic tweezing, by rupturing a Streptavidin-Biotin bond, a process which will be observed by tracking the motion of the colloidal particles on the substrate in a range of uniformly applied magnetic field.The *broader impact* of this work lies in the development of self-assembly "inspired" instrumentation for probing biomolecular interactions. The proposed magnetic tweezers enable investigation of force loading rates spanning a wide range of time scales from milliseconds to hours, a spectrum which is mostly inaccessible to the widely employed atomic force microscopy technique for stretching molecules. The parallel nature of this technique will be adapted to perform competitive binding assays, in which tweezing of multiple particles is performed simultaneously on an array of different chemical patches, thereby enabling a statistical distribution of unbinding forces to be measured in a single experiment. The PI and co-PI have a track record of encouraging participation of undergraduate and graduate students in research and education, particularly the hearing impaired and African-American minority students, who will spend two summer months in the in the PI's laboratory performing molecular stretching experiments.

0625480耶伦摘要该项目的目标是开发大规模并行的“假想”磁镊子，用于量化分子间的结合力。与传统的使用大型外部磁体对胶体颗粒施加磁场梯度和作用力的磁镊子不同，所提出的假想镊子系统的独特之处在于，作用力是由粒子与其自身图像在平面衬底上的近场相互作用产生的。这种图像排斥是通过将胶体颗粒浸入磁性纳米颗粒溶液中实现的，这种溶液被称为磁流体。这项提议的主要目标是通过打破链霉亲和素-生物素键来证明假想的磁钳的“原理证明”，这一过程将通过跟踪胶体颗粒在一系列均匀施加的磁场中的运动来观察。这项工作的“更广泛的影响”在于开发用于探测生物分子相互作用的自组装“启发”仪器。所提出的磁镊子能够在从毫秒到小时的广泛时间范围内研究力加载速率，这一光谱对于广泛使用的用于拉伸分子的原子力显微镜技术几乎是无法获得的。这项技术的并行性质将适用于进行竞争性结合分析，其中多个颗粒的钳取同时在一组不同的化学贴片上执行，从而使解结力的统计分布能够在单个实验中测量。PI和共同PI在鼓励本科生和研究生参与研究和教育方面有着良好的记录，特别是听力障碍和非裔美国少数民族学生，他们将在PI的实验室里度过两个夏天的时间，进行分子拉伸实验。