Acoustic tethering of microorganisms

We show how to construct and apply a setup to acoustically tether and enable behavioral observations of individual microorganisms using simple laboratory equipment and a standard light microscope. We explore the capability of the setup with the freely swimming dinoflagellate Alexandrium minutum as the study organism. The setup allows us to tether cells in focus in the mid-plane of the sample chamber and make observations of individual organisms at high magnification without affecting their flagellar beat frequencies. We discuss the prospect of the method to explore appendage motion and swimming kinematics of other flagellates and ciliates, and we argue that the method will be applicable to a broad range of cell sizes and shapes.

Automated summary

This study demonstrates the construction and application of an acoustic tethering setup for behavioral observations of individual microorganisms using simple laboratory equipment and a standard light microscope. The setup allows tethering of cells in focus in the mid-plane of the sample chamber, enabling high magnification observations without affecting flagellar beat frequencies. The method has the potential to explore appendage motion and swimming kinematics of various flagellates and ciliates.