Bio-affinitive, nanosized polymeric micelles with glucosamine in their corona have a specific interaction with Concanavalin A. They are prepared by a substitution reaction of p-nitrophenol groups in the poly(p-nitrophenyl acrylate) (PNPA) corona of stable micelles with glucosamine. The nanosized, stable, and reactive micelles are formed by self-assembly of the diblock copolymer, poly(p-nitrophenyl acrylate)-block-polystyrene (PNPA-b-PSt) in nitromethane, followed by a shell cross-Linking reaction. This method may be useful in the preparation of targeted drugs.