A hybrid spiral microfluidic platform for separation of circulating tumor cells

In this study, a hybrid microfluidic platform consisting of passive and active components was simulated to obtain a precise and enhanced separation of circulating tumor cells (CTCs). In the first stage of the system, the focusing of particles of varying sizes representing different cell lines was achieved by a two-loop spiral microchannel structure which was followed by exposing the standing surface acoustic waves (SSAW) to the particles. The merger of inertial focusing with SSAW facilitated the trapping of the particles along nodal lines leading to the five outlets and the proposed two-step approach was shown to increase the sensitivity of separation as indicated by the excellent localization of the 20 μm particles along the nodal lines whereas the 6 μm and 9 μm showed clear dispersion and mixing.