Pneumatic transport system for associative learning in Drosophila melanogaster

Abstract

A widely used associative learning technique for biological studies involves introducing Drosophila larvae to two different odorants and associating one of the odorants with a stimulus. The experimental method requires transferring the larvae back and forth between two odor chambers. Each chamber contains a different odorant and one of the chambers contains an accompanying stimulus. By introducing the larvae to the two different odorants several times, the larvae are trained to commit the odorant associated with the stimulus to memory. We created a mechatronic system for transporting Drosophila larvae back and forth between two agar trays to reduce manual labor and enable a scalable platform for associative learning and related studies. Air was chosen as the means of transporting the larvae and a chamber was constructed for housing the two agar trays. Control electronics were implemented for creating a sweeping blowing motion to transport the larvae in a gentle manner. Computer aided design (CAD) software was employed in conjunction with a 3D printer to build nozzles which help to direct airflow. Flow analysis software was utilized to model computational fluid dynamic simulations for optimizing air nozzles. In this study, a pneumatic transport system was developed and tested. The experimental results showed a 90% success rate for the transportation of larval Drosophila across the chamber and an overall decrease in transportation time by 4.8 times compared to manual transportation.