Fig. 1.

Workflow to enrich microalgae using PicoShell particles. 1) PicoShells are formed using droplet microfluidics, an aqueous two-phase system, and polymer chemistry. Particles are initially formed within an aqueous droplet surrounded by oil. Microalgae are within the dextran phase, which is surrounded by a solidifying PEG matrix. 2) Soon after particle formation, the particles are transferred into the algae’s native media. Pores in the solid outer shell allow for dextran to leak out and for continuous solution exchange. 3) Microalgae can divide within particles over multiple days to form clonal populations. 4) Pores in the solid matrix allow algal lipids to be fluorescently labeled. 5) High-performing populations can be sorted using FACS with scatter and/or fluorescence readouts. 6) Sorted particles can be broken down mechanically or by adding chemical reagents that degrade the PicoShell’s solid matrix, allowing associated cells to be released. 7) Released cells remain viable and can be recultured for further analysis and/or sorting.