Chip Design

Our Different designs

Introduction and first idea

Idea design of microfluidic chip

One of the biggest challenges of circulating tumor cells is their scarcity in the blood of patients. To overcome this problem, our first idea was to develop a microfluidic chip in order to perform single cell analysis. The biggest advantage of using a microfluidic chip is its ability to perform high-throughput cell biology. In order to do so, we wanted to produce water-in-oil emulsion droplets, that can then be sorted by a machine analogous to FACS, (inspired from [Chiu 2015]). In the droplets, a mixture of bacteria and mammalian cells would be present. And the bacteria would express the green fluorescent protein only in the presence of cancer cells, exhibiting both increased lactate production rate and sensitivity to sTRAIL.

First Design

First design of the microfluidic chip

However due to the complexity of this setup, we decided to first explore another design consisting of valves and chambers. Instead of having droplets to isolate single cells, we wanted to have a two-layer microfluidic chip. One of the layer would have been the flow of cells and the other layer, valves controlled by pressure that are able to close the chambers. We drew the designs using Autocad. On the figure, the orange layer represents the pressure control of the valves and the red layer represents the flow of the liquid.

Realistic and Final Design

Final design of the microfluidic chip

Because of time constraints, we did not make the previous chip but instead we designed a "nano-well" plate which represents our proof of principle. Here, there is no flow going through the chip. Characteristics of the chip

• The volume of every well is 1nL.
• There are 4992 wells in our chip.

Fabrication of the chip