Team:TU Eindhoven/Microfluidics/Introduction

Introduction

A substantial part of the TU Eindhoven iGEM 2014 Project is microfluidics. Microfluidics is a technique that comprises various fields of engineering. This technique operates on a micrometer scale and thus uses small volumes. It is therefore an excellent technique to be applied for example in the field of synthetic biology. It offers rapid processing and precise control of fluids in an assay and costs of reagents can be reduced due to its use of small volumes [1]. For the encapsulation of bacterial cells, droplet-based microfluidics is used. As is elaborated in the Project Description, the engineered bacteria must be brought into the proximity of DBCO functionalized molecules. The final goal is to verify the intended function of a cell encapsulation device. To achieve this, three processes have to be accomplished:

1. Combining a solution with DBCO functionalized PEG polymers and a bacterial culture with our engineered bacteria. These are the essential substances to perform the click reaction. After combining, this is called the continuous phase.


2. The continuous phase has to be dispersed with an oil phase into droplets. This oil phase contains a fluorosurfactant in order to prevent aggregation and agglomeration of the droplets. It is crucial to form droplets with one cell in each droplet, since it will assure that each induvidual bacterial cell is encapsulated correctly – possible formation of a film is hereby avoided.


3. The result of the previous two processes is a droplet including PEG and engineered bacteria inside an oil phase. With a microfluidic feature (bumpy mixer) the droplet can be stirred. The droplets are collected in a chamber where the click reaction is initiated with the use of UV light.

Before these processes can be performed, certain questions have to be answered and certain research has to be done. For instance, how is it possible to form droplets? What is the optimal method to recollect the content of the droplets? What is the required flow speed of the continuous phase and oil phase and what are the viscosities of these phases?

Figure 1. TU Eindhoven iGEM 2014 in a microfluidic device.

Bibliography

[1] Eric K. Sackmann, Anna L. Fulton & David J. Beebe. (2014) “The present and future role of microfluidics in biomedical research.” Nature. Vol. 507. doi:10.1038/nature13118.