Magnetic nanoparticles for direct protein sorting inside live cells

This work reports the first example of the biofunctional magnetic nanoparticles as a "magnetic dock" for directly sorting proteins inside live cells. We decorate the iron oxide nanoparticles with the ligands that bind selectively to fusion proteins consisting of the proteins of interest (POIs) and the ligand receptors. Similar to protein sorting processes on vesicles, the clusters of these functionalized magnetic nanoparticles only bind to the fusion proteins via the interaction with the receptors, but exhibit little interaction to other proteins. This work demonstrates new applications of magnetic nanoparticles and may ultimately contribute to the exploration of the functions of proteins via the selective, spatiotemporal control of the proteins by a magnetic force.