Microorganisms in vortices: a microfluidic setup

Marcos, Roman Stocker

Limnol. Oceanogr. Methods 4:392-398 (2006) | DOI: 10.4319/lom.2006.4.392

ABSTRACT: A method is presented to create microscale vortices using a microfluidic setup specifically designed to investigate the response of swimming microorganisms. Stable, small-scale vortices were generated in the side cavity of a microchannel by the shear stress in the main flow. The generation of a vortex was found to depend on the cavity’s geometry, in particular its depth, aspect ratio, and opening length. Using video-microscopy, the position and orientation of individual bacteria and algae swimming in vortices of various strengths were tracked. Elongated cells were found to align with the streamlines in a strong vortex. The experimental system provides quantitative single-cell information on the interaction between microorganisms and their fluid dynamical environment.