Hong Yifeng, Ye Fan, Gao Xiang, Inman James T, Wang Michelle D
Department of Electrical and Computer Engineering, Cornell University, Ithaca, NY 14853, USA.
Howard Hughes Medical Institute, Cornell University, Ithaca, NY 14853, USA.
bioRxiv. 2024 Sep 27:2024.09.25.614944. doi: 10.1101/2024.09.25.614944.
The angular optical trap (AOT) is a powerful technique for measuring the DNA topology and rotational mechanics of fundamental biological processes. Realizing the full potential of the AOT requires rapid torsional control of these processes. However, existing AOT quartz cylinders are limited in their ability to meet the high rotation rate requirement while minimizing laser-induced photodamage. In this work, we present a novel trapping particle design to meet this challenge by creating small metamaterial elliptical cylinders with tunable trapping force and torque properties. The optical torque of these cylinders arises from their shape anisotropy, with their optical properties tuned via multilayered SiO and SiN deposition. We demonstrate that these cylinders can be rotated at about 3 times the rate of quartz cylinders without slippage while enhancing the torque measurement resolution during DNA torsional elasticity studies. This approach opens new opportunities for previously inaccessible rotational studies of DNA processing.
角光学阱（AOT）是一种用于测量基本生物过程中DNA拓扑结构和旋转力学的强大技术。要充分发挥AOT的潜力，需要对这些过程进行快速扭转控制。然而，现有的AOT石英圆柱体在满足高旋转速率要求的同时，将激光诱导的光损伤降至最低的能力有限。在这项工作中，我们提出了一种新颖的捕获粒子设计，通过制造具有可调捕获力和扭矩特性的小型超材料椭圆圆柱体来应对这一挑战。这些圆柱体的光学扭矩源于其形状各向异性，其光学特性通过多层SiO和SiN沉积进行调整。我们证明，这些圆柱体在DNA扭转弹性研究中，在不发生滑动的情况下，能够以大约石英圆柱体三倍的速率旋转，同时提高扭矩测量分辨率。这种方法为以前无法进行的DNA加工旋转研究开辟了新的机会。
