Momentum transfer through synthesized biopolymer network meshes with optically trapped anchor points

在过去的二十年中，光阱在软物质物理和生物物理学中已经证明了其巨大的潜力。尽管几乎任意的潜在景观可以相当灵活地生成，但其中的粒子运动和驱动力通常难以测量。仅简要地表明，通过光学陷阱的快速时间复用，可以在三维空间中平行跟踪大约100个粒子，达到几千赫的速率和纳米精度。所有点陷阱的独立校准允许以高精度和灵敏度测量动态力场。任意力场的产生和测量使得研究基于自然模型的新型智能软材料成为可能。在这个提议中，我们的目标是通过自下而上的方法建立一个生物聚合物网络，其中每个基本细胞都通过光学陷阱建立起来，以便与下一个细胞连接。微管是活细胞内细胞骨架的重要组成部分，将以化学稳定的形式结合到涂覆的乳胶珠上。每个珠子位于可变二维排列的光阱内，并作为网络的锚点。通过对网络一端进行不同频率的机械扰动，可以在另一端研究动量的传播和不同网格结构传递的粘弹性响应。

During the last two decades, optical traps have proven their enormous potential in soft matter physics and in biophysics. Although nearly arbitrary potential landscapes can be generated quite flexibly, particle motions therein and driving forces are often difficult to measure. Only briefly it has been shown that by fast time-multiplexing of an optical trap, parallel tracking of about 100 particles is possible in three dimensions achieving a rate of several kHz and nanometer precision. An independent calibration of all point traps allows for measuring dynamic force fields with high precision and sensitivity.The generation and measurement of arbitrary force fields makes it possible to investigate new intelligent, soft materials based on the model of nature. In this proposal we aim to set up a network of biopolymer through a bottom-up approach, where each elementary cell is set up by optical traps to be connected with the next cell. Microtubules, which are an important part of the cytoskeleton inside living cells, will be bound in chemically stabilized variant to coated latex beads. Each bead sits inside an optical trap within a variable two-dimensional arrangement and serves as an anchor point of the network. By disturbing the network mechanically and at different frequencies at one end, the propagation of momentum and the visco-elastic response transferred by different mesh configurations can be studied at the other end.