Integrated Single Camera µPTV And Florescence Imaging For Cell Tracking And Flow Investigation In Centrifugal Microfluidic Devices

Abstract

A micro-hydrocyclone is investigated as a high throughput particle/cell sorting microfluidic device. A complex flow structure has been reported by limited numerical works that increases the importance of undertaking a comprehensive experimental investigation. In addition to the flow, utilizing damageable bio cells in a micro-hydrocyclone, requires a deep understanding of the interaction between the cells entering the device, the flow structure and its instabilities forming in different operational phases. In such cases the implementation of multiple measurement techniques can be challenging due to the small scale of devices, here < 5 mm diameter. Therefore, for this complex flow an experimental approach is introduced to capture the flow structure and the motion of cells. In this method, tracer particles and fluorescent stained cells are captured simultaneous by a single camera in the same flow field. A custom image processing scheme is used for partitioning cells and particles from the raw data. To determine velocity vectors, µPTV is employed on the segmented data sets to study the effect of flow on trajectory and velocity of each individual cell in the system. By a combined investigation in a vast range of Reynolds number (50<Re<800) the dynamics of cells are investigated in response to different flow structures and flow regimes.