NEW Application Note: A quick and efficient double emulsion generation method for flow cytometry droplet sorting

In this paper, we describe the encapsulation of a fluorescent strain of Escherichia coli bacteria in w/o/w double emulsions and flow cytometry droplet sorting using a flow cytometry cell sorter (also commonly known as FACS). The Secoya’s RayDrop platform (including the RayDrop^® device and distributed by Fluigent) allows the bacteria to be compartmentalized within a protective shell and ensures compatibility with the sorting device. The platform generates double emulsions in one step, scaling the production of common two-step double emulsion generation methods by up to ten times. Several hundred microliters of emulsions can be produced in 30 minutes, and multiple conditions can be tested within a single day, compared to a week with traditional methods. In addition, the platform integrates fluidic, pneumatic, and optic solutions, and does not require complex fabrication steps nor surface treatment. This application note was written in collaboration with Delphine Lestrade (head of the flow cytometry platform at Toulouse White Biotechnology, TWB) and Sophie Lajus (researcher at the Toulouse Biotechnology Institute, TBI)