An automated microfluidic platform for calcium imaging of chemosensory neurons in Caenorhabditis elegans.

Functional fluorescence imaging methods are widely used to study cellular physiology. When applied to small organisms, these methods suffer from low-throughput due to the laborious immobilization/stimulus delivery procedure that is typically involved during imaging. Here, we describe the development of an automated microfluidic-based platform for performing automated neuronal functional (calcium) imaging in the roundworm Caenorhabditis elegans. The platform, capable of processing tens to hundreds of worms per hour, immobilizes individual worms, delivers a chemical odor to their nose and collects calcium imaging data from single neurons without any manual intervention. We used the developed platform to obtain a large number of calcium responses from worms of different ages (212 worms were imaged in total). The calcium imaging data revealed significant difference in the responses from young and old worms, indicating that neural functionality is age-dependent. We believe that such a technology will be an essential tool for obtaining repeatable and accurate functional imaging data from a large population of worms, in order to minimize stochastic biological noise and identify statistically significant trends.

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