A method of forming polymeric microspheres for biomedical applications includes forming polymeric microspheres by an emulsion/aggregation process from a precursor monomer species, and treating the polymeric microspheres to attach a biomedical functional material to the polymeric microspheres, where the polymeric microspheres have an average particle diameter of from about 1 to about 15 microns with a narrow particle geometric size distribution. The biomedical functional material may be, for example, a radioactive material, a radioactive precursor material, a bioactive agent, or a ligand.