Automated Stimulation and Long-Term Remote Monitoring of Multi-Plex Microfluidic Organoid Chips

Abstract

Developing a novel microfluidic organoid system required many experiments and iterations due to lack of knowledge about the relevant developmental biology. Collecting data on the developing organoids quickly escalated into a bottleneck as high throughput and long term culture resulted in a rapidly increasing number of specimens being observed. Commercially available automated microscope systems exist, but were either too expensive or not appropriate, and could not be modified. To satisfy the increasing need for automated data collection, a custom robotic system was developed to collect data from within a standard incubator. An X-Y belt driven gantry was designed with an architecture chosen to balance high accuracy, low cost, speed, and range of motion. Focus control was implemented with dual miniature leadscrews. A linear sliding mechanism was used to switch between two microscope objectives. 3D printed chip attachments were designed to implement illuminators for bright field imaging, and electrodes for stimulating the cardiac organoids. A fluorescent filter block was designed using a 3D printed piece to hold optical components, and a multi-band filter set that allowed for three color fluorescence without moving parts. A pulley driven tilting stage gravitationally biased the organoids during development. In order to ensure accurate image collection despite the inevitable position shifting of the chips, an image processing pipeline was developed for locating organoids using geometrical microfluidic chip features. The resulting robotic system automated imaging data collection on organoids and electrical and mechanical stimulation, in addition to being modifiable for future projects.