“…1, the most useful synthetic approach would allow control over the ONP: (1) size, (2) hardness (i.e., exibility), (3) solubility, (4) external functionality, (5) internal functionality, and (6) density/porosity, as well as being (7) scalable and (8) producing ONPs of low toxicity and high biocompatibility for bio-applications and low environmental impact. Finally, having a single reactive functional group on the ONP surface is very useful for controlled nanoscale assembly 8 and two orthogonally reactive functional groups 9 would provide access to an even broader set of applications. Obtaining ONPs with a limited number of reactive groups is a particular challenge because nanoparticles are invariably prepared with a large number of identical groups on their surface.…”