On-demand dielectrophoretic immobilization and high-resolution imaging of C. elegans in microfluids

Abstract

Caenorhabditis elegans (C. elegans) is a significant model organism in scientific research. However, considerable operations, such as neuron microcurgery and monitoring of development, require to silence the worm to achieve high-resolution imaging. To date, immobilization techniques being on-demand, low-injury, rapid, reversible, and easy to implement is highly desirable. This paper reports a dielectrophoretic method for on-demand immobilization of C. elegans in a microfluidic environment. Using thick electrodes and optimized parameters, we achieved high-efficiency and reversible immobilization of C. elegans of different stages, and demonstrated successful high-resolution imaging of immobilized nematode for important application. To the best of our knowledge, this is the first report showing on-demand, highly-efficient, and reversible immobilization of C. elegans for high-resolution imaging with uniform dielectrophoretic (DEP) forces generated from thick all polydimethylsiloxane (PDMS) electrodes. We believe this simple, efficient sensing and actuating lab-on-a-chip platform can largely facilitate the research of C. elegans biologists.