A microfluidic platform for the immobilization and imaging of C.elegans throughout its entire life cycle.

Caenorhabditis elegans is used as a model organism in the study of developmental biology and neurobiology. Among its many advantages, C. elegans has a transparent cuticle, rapid life-cycle, and invariant somatic cell number, making it a powerful model.

Moreover, the advantage of its small size (10um-1mm) may allow the development of a platform that allows real-time monitoring of the warm throughout its entire life cycle.

The present study presents a series of new microfluidic devices, that were developed in our laboratory for the study of C. elegans throughout its entire life-cycle using high-resolution microscopy. Our aim is to develop and optimize a semi-automated microfluidic device for this purpose. As so, this device has to be calibrated and optimized for fluids flow rate, feeding procedure, and immobilization pressure and durations that may be applied during the worm life cycle. Hereby we present three different approaches for worm immobilization: lateral mechanical pressure, liquid lateral flow pressure, and upper mechanical pressure. Results showed an optimized flow rate of 5µl/min for worm insertion into the chip. A tolerated upper pressure of 13psi for 60 minutes induced no damage to the worm locomotion abilities, which return to normal within 5-10 minutes post releasing. Such immobilization allows long-term imaging at the single-cell level without chemical anesthesia. We believe that this model is suitable for real-time and continuous monitoring of various mechanisms of interest in the life cycle of C. elegans, from the L1 stage up to mature worm.