A method of preparing multifunctionalized nanoparticles involves using a modular system of half-linkers to attach functional moieties that serve to deliver the nanoparticles to a desired target, exert an effect at the target, or track the nanoparticles within a cell or an animal. The modular chemistry of the half-linker system permits the custom design and synthesis of functionalized nanoparticles bearing multiple groups and therefore results in precise delivery to desired cell types and intracellular locations. The functionalized nanoparticles can be used to treat or diagnose a variety of medical conditions, including neoplastic diseases, infectious diseases, and chronic diseases.
