Synthesis and Characterization of Functionalized Magnetic Microspheres for Biomedical Applications

This study employs an innovative two-step method: first, polystyrene-methyl methacrylate copolymer microspheres (P(St-MMA)) are prepared via a dispersion polymerization process, followed by the introduction of a coprecipitation reaction to synthesize magnetic microspheres with varying magnetic content. These microspheres are then reacted with sodium hydroxide to yield carboxyl-functionalized products (P(St-MMA-COOH)). Characterization revealed that the molecular structure of the microspheres aligns with expectations, exhibiting a regular spherical shape, good monodispersity, a narrow particle size distribution, a large specific surface area, uniform element distribution, high thermal stability, high saturation magnetic induction intensity, and excellent physical stability. When utilized in fully automated chemiluminescent immunoassays to evaluate the detection and purification efficiency of Interleukin-6(IL-6), the results indicated that the coefficient of variation (CV) for all three magnetic content microspheres was <5%, confirming their excellent stability, good batch-to-batch reproducibility, and high uniformity of key parameters, thereby ensuring experimental reliability. These microspheres combine excellent biocompatibility, controllable separation capabilities, and flexible modification potential. This provides a new idea for chemiluminescent immunoassays.