Benjamin Owen

Inertial microfluidics offers powerful opportunities for label-free cell separation, but device performance is governed by an increasingly complex combination of inertial migration, cell–cell interactions, mechanical properties, and interactions with device features. In this talk, I will present a series of computational studies aimed at understanding and ultimately exploiting these effects for improved microfluidic design.

I will first discuss our work on the separation of circulating tumour cells (CTCs) from white blood cells, showing how cell size and mechanical properties influence migration and how interactions between different cell populations can alter separation performance. I will then extend this picture to dense suspensions, where particle–particle interactions compete with inertial migration and lead to collective behaviour that cannot be predicted from isolated-particle trajectories alone.

Building on these observations, I will introduce our recent work using flexible filaments within inertial microfluidic channels. These structures deform in response to the flow and provide a route towards actively reshaping particle trajectories, with the longer-term aim of developing adaptive microfluidic separation devices.

Finally, I will highlight recent advances in our computational cell models, including approaches that allow increasingly realistic descriptions of cell deformation and cell–fluid interactions. Together, these studies demonstrate how numerical modelling can complement experiments by revealing the physical mechanisms underlying separation and by enabling the exploration of new microfluidic concepts before fabrication.