Magnetic Microtweezers: A Tool for High‐Throughput Bioseparation in Sub‐Nanoliter Droplets

Droplet microfluidics has revolutionized the field of single-cell analysis. Production micro-droplets at high throughput allows for rapid isolation single cells within micro-compartments, which are then subjected to different analytical processes. However, certain operations, such as physical separation from droplets, remain difficult implement and level but would be highly valuable currently expanding multiomics techniques, where several biomolecular modalities involved. This work presents a method based on microfabricated NiFe structures, magnetic microtweezers, trap extract particles continuous stream sub-nanoliter enable cell-based droplets. Using model, simulations, experiments, comprehensive description complex particle extraction process is provided. After optimization, microtweezers provided unprecedented performance, allowing loads (10-20 ng) 500 pL with capture rate close 100% 20 Hz. To evaluate applicability analysis, mRNA performed. It demonstrated around 72% specific recovery droplets containing purified nucleic acids, 43% cells. Overall, this approach enables efficient that compatible existing high-throughput droplet-based workflows.