High-Speed Sorting of Sub-20 nm Chiral Particles via Toroidal-Enhanced Separated Potential Wells

Enantioselective sorting at the nanoscale is highly significant in fields such as medical research, material science, and drug development. However, previous studies mainly focus on static chiral particle separation, hindering practical applications. Here, we utilize the synergy between enantioselective potential wells and flow fields to sort nanoparticle enantiomers at a high velocity of 800 μm/s. An enhanced chiral field induced by the mirror-enhanced toroidal dipole is employed to amplify the chiral gradient force, creating separated potential wells for opposite chirality. By regulating the synergy of chiral gradient force and fluidic drag force, we achieve sorting of 20 and 200 nm chiral particles with separation distances larger than 32 and 48 μm in a sorting area of 70.96 × 70.96 μm², respectively. Furthermore, efficient static separation of 20 nm chiral particles is also demonstrated with their separated potential wells. Our work holds tremendous potential in biotechnology, nanotechnology, and pharmacology.