Laser-Manufactured Magnetic Microchips for Exosome Isolation and Patterning

We report the development of a laser-based micromagnet patterning process and magnetic microchip architecture enabled by this process which facilitates isolation of exosomes via pattering of magnetic composite. The laser-based manufacturing process supports raw material to device manufacturing in <30 minutes and enables patterning with microscale lateral resolution (<50 μm), high throughput (400 mm/s), and over large areas (>in
²
), without lithographic processing. Using finite element analysis (FEA), we have further optimized individual micromagnet unit cells, resulting in a geometry that was implemented within exosome capture studies. The magnetic microchip architecture introduced herein, consisting of fluid-invasive micromagnets, enables the generation of high magnetic gradient fields throughout the fluid medium rather than confined to the channel walls within standard microfabricated magnets, showing >80% capture efficiency from simulation and on micromagnet exosome patterning.