An in-vitro living system for flow rectification

Conventional applications using viscous streaming overwhelmingly utilize classically understood bodies that are rigid and of simple shape and topology, offering limited opportunities for flow manipulation. Taking advantage of recent computational insights into body-topology effects on streaming flows, and biofabrication advances, we present the first in-vitro realization of a living biological muscle ring able to elicit complex rectified flows. Using a synergistic experimental and numerical approach, we characterize this flow response to identify the distinct footprint of viscous streaming.  This streaming system marks a significant milestone towards the design and fabrication of independent, self-sustained, active, and biocompatible entities capable of flow manipulation at the microscale, opening avenues for transport, mixing, and trapping across a spectrum of applications, from engineering to medicine.