The experiment setup  keeps a constant flow of fluid through the chip at all times while ensuring no bubbles enter. A series of Y-connectors and 1.5 mm OD microbore tubes allow this fluid to travel from the 1 mL dispensing syringe, through the chip, and into a waste receptacle on the other side. This fluid flow is maintained a flowrates between 0.2 and 3 μL/min throughout the experiment with the syringe pump. The system was designed to allow full functionality with only a single syringe pump and a minimal footprint to fit within the confines of the confocal microscope enclosure during imaging and data collection. In addition, the system was designed to minimize the time the operator needs to be present or interact with it to allow the experimental procedure to be easily learned and conducted. 

The deterministic lateral displacement (DLD) filter sorts the incoming cells according to size passively through flow around specially designed pillars in the chip. This chip consists of two inlet ports, two outlet ports, and a 50x780 pillar array. The inlet/outlet ports are offset from the main array to prevent interaction with the microscope lens during imaging. The inlet ports expand to the size of the main channel non-symmetrically to introduce the incoming cells on one side of the filter in order to allow the large cells time to deflect. Additionally, support pillars are located throughout the entirety of the chip to prevent the PDMS from sagging and closing off the channels.

The cells will follow the streamlines of the flow, defined by the pillar size, pattern, and the boundary conditions at the edges. Cells whose size are above the critical diameter of 10 μm will laterally displace due to collision with the pillars. Cells of smaller sizes will directly follow the streamlines, zig-zagging through the array of pillars. As a result, the larger cells will collect into one outlet port and the smaller cells will collect into another outlet, successfully separating the cells. Additionally, support pillars are located throughout the entirety of the chip to prevent the PDMS from sagging and closing off the channels.

The Hydrodynamic Trap Array chip consists of an inlet, an outlet, two flow separators, and the central trap array. The inlet and outlet are offset from the main body channel to prevent interaction between the microbore tubing into the chip and the microscope lens. The bicarbonate-free media is injected with the cells and interacts with the flow separators, two triangular features which distribute the flow across the entire channel, maximizing the number of traps interacting with the incoming cells.  Each trap consists of a larger front cavity and a smaller rear cavity, patterned across the channel such that a reverse in the flow direction, as described below, successfully traps two cells of different sizes. Additionally, support pillars are located throughout the entirety of the chip to prevent the PDMS from sagging and closing off the channels.