See-through cartridge for real time monitoring of tumor cells capturing on microfilters

In metastasis process, it is hypothesized that tumor cells detach from the primary tumor and are released into the bloodstream and to distant sites, forming secondary tumors. To use these Circulating Tumor Cells (CTC) as a cancer biomarker, significant research has been directed to the development of devices capable of detecting and enumerating CTCs. Size-based isolation approach using microfilters has been effectively developed to capture CTCs. However due to the lack of capability for live monitoring the tumor cell capturing on the filter, the optimization of the current filter-based devices for capturing heterogeneous CTCs is very challenging. We report a low-cost cartridge with a see-through site enabling the enumeration of tumor cells and imaging cells entrapment on the filter which help to characterize the parameters involved in the capturing process. Real time imaging along with the pressure and flow control assist to simply correlate the pressure on the filter, the cell velocity and flow rate, and the entrapment of cells from the pores. Based on the velocity of cells over pores, an appropriate flow rate was selected and the capture efficiency of breast cancer cells was then measured for different filter pore sizes. The device will be a breakthrough platform for the current filter-based detection devices with high potential for optimization of the isolation parameters, and to find out how these parameters may affect the squeezing of tumor cells through the pores and, as a result, the reduction of the capture efficiency.