(465d) Design and Simulation of an Automated Rare Blood Cell Detector

Design and Simulation of an Automated Rare Blood Cell Detector

Zhixi Qian^a, Eugene D. Boland², Paul W. Todd², and Thomas R. Hanley¹

¹Department of Chemical Engineering, Auburn University, AL 36849

²Techshot, Inc., 7200 Highway 150, Greenville, IN 47124

Abstract

            Detecting circulating tumor cells (CTC) can play an essential role in cancer early detection and treatment.  However, CTC detection devices are  limited to laboratory use due to cost and complexity.  A simple-to-operate point-of care cell detector can help in detecting CTC at small clinics, nursing homes and patients’ homes.  Our goal is to design such a point-of-care CTC detector.  The processes of cell labeling using a static mixer and magnetic separation using a unique magnetic cell trap have been simulated using computational fluid dynamics (CFD) software.  Models for static fluid mixing as well as magnetically labeled cell tracking were developed and tested numerically and experimentally.  We established relationships between magnetic ponderomotive force and magnet pole strength using modified magnetic particle velocity formulas and a detailed description of magnetic particle and cell motion within a three-stage magnetic trap.  By simulating a balance among diffusion, flow rate and sedimentation, we predict optimized values for the combined mixing and magnetic capture processes.  Finally, using a model combination of whole blood, tumor cells from cultures and immunomagnetic labeling reagents in laboratory experiments, the CTC detector is shown to be able to label and capture the minor CTCs in blood samples.

Key words:  circulating tumor cells; CFD simulation; magnetic separation; cell labeling; static mixer