Acrylamide (AAm)-methacrylic acid (MAc)-methylenebisacrylamide (MBAAm) terpolymer microspheres and AAm-MAc-MBAAm-nitrophenyl acrylate (NPA) quaterpolymer microspheres with high monodispersity were prepared by precipitation polymerization in alcohol. The former were modified into composite microspheres containing hydrophobic domains or magnetite nanospheres. The active ester in the quaterpolymer microspheres was allowed to undergo hydrolysis or aminolysis to prepare novel microspheres such as highly negative, amphoteric, hydrophobic or bioconjugate microspheres.