Vision-Based Cellular Force Measurement Using an Elastic Microfabricated Device

Manipulation and characterization of individual biological cells require cellular forces be precisely measured in real time. This paper presents a computer vision-based cellular force measurement platform that allows for the use a single vision sensor to simultaneously obtain two forms of feedback (i.e., vision and force). A novel silicone elastomer-based cell holding device and a sub-pixel visual tracking algorithm are developed. Deflections of elastic, low-stiffness structures are visually tracked, and material deflections are subsequently transformed into cellular forces. Experimental results demonstrate that the current vision-based force sensing system is capable of performing robust cellular force measurements at a full 30 Hz with a 3.7 muN resolution. Importantly, the vision-based cellular force sensing framework established in this study is not scale or cell line dependent. The device design, visual tracking algorithm, and experimental technique form a powerful framework that permits visually resolving cellular forces in real time with a picoNewton (26 pN) resolution for applications in single cell manipulation and characterization