Centrifugal Step-Emulsification Platform for High-Throughput Emulsion Screening

A centrifugal emulsification platform enabling the parallel generation of emulsions directly in standard 96-well plates is introduced. Upon centrifugation, the dispersed phase is driven through capillaries into the continuous phase, where step emulsification yields droplets by clean pinch-off. The system achieves high reproducibility, with success rates above 90%. The platform's utility is demonstrated by screening silicone-oil/water emulsions across siloxane surfactants and NaCl gradients, and by mapping fluorinated emulsion stability as a function of salinity and the mixing ratio of two fluorinated surfactants of different chain lengths. In contrast to lab-on-a-disc systems or single-tube centrifugal devices, this approach combines minimal hardware requirements with high throughput and seamless compatibility with automated liquid-handling and imaging workflows. Its simplicity and scalability make it suited for closed-loop optimization, accelerating the discovery of sustainable non-fluorinated droplet systems and enabling systematic studies of emulsion stability across diverse formulation spaces.