Receptor-targeted nanoparticles (R-NPs) are provided for selective transport into and through targeted tissues of therapeutic, prophylactic and diagnostic agents. R-NPs can include polymeric particle, lipid particles, inorganic particles, or a combination thereof with a targeting moiety selective for binding to a receptor on the cells where the agent is to be delivered, where the receptor mediates transcytosis of the nanoparticle into and through the cells. In a preferred embodiment, the targeting moiety is the neonatal Fc receptor. Examples demonstrate Fc-targeted nanoparticles which are actively transported across the intestinal epithelium, providing a route for the oral delivery of nanoparticle encapsulated active agents including peptides such as insulin.