Transforming C. Elegans Research Through Gigahertz Ultrasonic Imaging Microscopy

Abstract C. elegans is a model organism used for biological research across thousands of US and world labs for fundamental and transla�onal research. Due to the versa�lity of gene�c manipula�ons and its rela�vely short lifespan, C. elegans has been essen�al in studying aging, pathogenesis, molecular mechanisms, gene�cs, toxicology, and compound screening. Several protocols for the cul�va�on, maintenance, and performance of survival assays of C. elegans have been established and refined over �me. Despite these advancements, one of the significant limita�ons of C. elegans work is the manual effort and handling required for longitudinal phenotyping. Researchers must manually move adult worms across petri dishes to avoid confusion with the hundreds of progenies being produced that become adults within days. For a longitudinal assay, the movement of worms is monitored daily throughout their �ssue degenera�on, degrada�on, and eventual death. We propose to develop and understand gigahertz ultrasonic imaging of worms, to reduce the effort involved in worm research, and make the protocols repeatable across different laboratories, while developing a new phenotype for the C. elegans research community. Geegah has developed a 2D 256x256 25-micron pixel array using 2 GHz ultrasonic transmit/reflec�on. Geegah’s GHz ultrasonic pulses reflect with sufficient SNR to create images and real-�me movies of nematodes and C. elegans worms in petri dishes. In preliminary studies, Geegah's GHz ultrasonic imager has measured and iden�fied ultrasonic impedance differences between live (mobile, immobile), dead worms, and across different species of worms. The proposed work will first understand the GHz ultrasonic response of the worm anatomy by detailed analy�cal and FEM modeling. These models and images will be used to develop a phenotype based on ultrasonic maps of cu�cles. Lastly, an automated prober system will be designed and prototyped, with the end-effector being Geegah ultrasonic imagers, that can generate digitally annotated maps of worm ultrasonic proper�es and provide live/dead status in petri-dishes that are regularly used in C. elegans research labs.