Development of a Microfluidic Emulsion Generating Device for Increased Throughput

This paper deals with the creation of monodisperse emulsions using a microfluidic device. Emulsions can be used to simplify many tedious tasks such as PCR. In just 1 mL of sample volume, parallel reactions can take place in >10¹⁰ droplets of fL – nL size, greatly reducing reagent consumption and time over standard plate reader assays.  For many of these tasks, the interpretation of assay results relies on the assumption that all droplets receive the same amount of starting material. Therefore, droplet volume is an important factor.  Previous microfluidic chips used, either slowly generated monodisperse emulsions, or rapidly generated more polydisperse emulsions. We have parameterized a multi-channel, emulsion- generating device to rapidly generate droplets, while improving the consistency of emulsion size. The parameters selected for the new device include the creation of a thinner chip, a minimization of the number of inlets needed, and the utilization of an O-ring. The new device generated a monodisperse emulsion with a diameter range of 20-60 µm. This device still needs further testing to determine its viability as a substitute for the single channel generator. This testing would include using the device to generate emulsions with different concentrations of DNA and running PCR on the droplets.