Institute of Biological Chemistry, Biophysics and Bioengineering, School of Engineering and Physical Sciences, Heriot Watt University, Edinburgh, EH14 4AS, UK.
Optics and Photonics Research Group, Faculty of Engineering, University of Nottingham, Nottingham, NG7 2RD, UK.
Sci Rep. 2021 Mar 10;11(1):5614. doi: 10.1038/s41598-021-85013-y.
We introduce a novel 3D microrheology system that combines for the first time Optical Tweezers with Integrated Multiplane Microscopy (OpTIMuM). The system allows the 3D tracking of an optically trapped bead, with ~ 20 nm accuracy along the optical axis. This is achieved without the need for a high precision z-stage, separate calibration sample, nor a priori knowledge of either the bead size or the optical properties of the suspending medium. Instead, we have developed a simple yet effective in situ spatial calibration method using image sharpness and exploiting the fact we image at multiple planes simultaneously. These features make OpTIMuM an ideal system for microrheology measurements, and we corroborate the effectiveness of this novel microrheology tool by measuring the viscosity of water in three dimensions, simultaneously.
我们介绍了一种新颖的 3D 微流变系统，该系统首次将光镊与集成多平面显微镜（OpTIMuM）相结合。该系统允许对光学捕获的微珠进行 3D 跟踪，沿着光轴的精度约为 20nm。这是通过不需要高精度的 z 轴、单独的校准样品以及对微珠大小或悬浮介质的光学性质的先验知识来实现的。相反，我们使用图像锐度开发了一种简单而有效的原位空间校准方法，并利用同时在多个平面成像的事实。这些特性使 OpTIMuM 成为微流变测量的理想系统，我们通过同时在三个维度上测量水的粘度来证实这种新型微流变工具的有效性。
