Narrow-dispersed P(MMA-GMA-DVB) (PMGD) microspheres with different amout of DVB from 20 to 50 weight percentages were prepared by soap-free emulsion polymerization and polysuccinimide (PSI) was prepared by polycondensation of L-aspartic acid (L-ASP) using phosphoric acid as a catalyst in sulfolane/mesitylene solvent. Then, PSI was attached to the surface of PMGD microspheres containing different amount of DVB in N,N-dimethylformamide solvent. The elemental analysis results showed that the largest amount of PSI was attached to the surface of P(MMA-GMA-DVB) microspheres when the weight content of DVB was 40%. Then the remains of active rings of the PSI on the surface of microspheres were opened by ethanediamine, at last, fluorescent microspheres were achieved by reacting with fluorescein isothiocyanate (FITC).

Key words: soap-free emulsion polymerization, polysuccinimide, fluorescent microsphere