Patent ID: 8541503

Claim:
A method of making a polymeric nanoparticle, comprising: polymerizing at least one shell monomer and a second monomer to form a shell and an interphase region; attaching to the interphase region a core by copolymerizing at least one core monomer different than the at least one shell monomer and at least one crosslinking agent in the presence of the shell; and, crosslinking at least the core with the at least one crosslinking agent, thereby forming the polymeric nanoparticle; wherein the interphase region separates and connects the core and the shell; wherein one of the following steps is performed: a. the shell and interphase region are polymerized by adding the shell monomer, subsequently adding the initiator, and subsequently adding a simultaneous charge of the shell monomer and the second monomer; or b. the core is polymerized through incremental addition, by multiple charges or metering, of simultaneous amounts of core monomer and crosslinking agent.