1. Dissolve phospholipids in chloroform to 20 mM. 2. Dispense 50 μL lipid solution into glass test tubes. 3. Place tubes in a vacuum desiccator, evacuate overnight in the dark. 4. Store lipid dry films in a vacuum desiccator at room temperature, use within 1 month. 5. Mix mineral oil by gentle inversion before use. 6. Collect a lipid dry film sample from the desiccator. 7. Place 1 mL of mineral oil into a glass test tube, seal with heat-resistant film. 8. Incubate tube at 80 °C for 15 min in a dry bath incubator. 9. Dissolve the lipid dry film by vortexing for 10 s. 10. If undissolved, repeat steps 8-9. 11. Set tube in a floating rack and sonicate for 90 min at 60 °C, 60 W power. 12. Mix the lipid-oil mixture by vortexing for 10 s. 13. Cool to room temperature and incubate overnight in the dark. 14. Store the lipid-oil mixture at room temperature in the dark, use within 1 week. 15. Prepare a flow chamber using double-sided adhesive tape and coverslip. 16. Mix lipid-oil mixture by vortexing immediately before use. 17. Transfer 80 μL of the lipid-oil mixture into a microcentrifuge tube pre-equilibrated to a desired temperature. 18. Pipet 2 μL of protein solution into the lipid-oil mixture, mix by vortexing for 10-30 s to form water-in-oil droplets. 19. Perfuse the emulsion into the flow chamber, seal with Valap. 20. Observe droplets using an optical microscope.