The surface of magnetite (Fe3O4) nanoparticles prepared by a co-precipitation method was modified by the carboxylic acid group of meso-2,3-dimercaptosuccinic acid (DMSA). The egg white lysozyme was then immobilized on the carboxylic acid group-modified magnetite nanoparticles. The magnetite nanoparticles were approximately 10 nm and had a spherical morphology and uniform size distribution. The concentration of lysozyme on the modified magnetite nanoparticles was also investigated by a UV-Vis spectrometer and compared to that of magnetite nanoparticles without surface modification.

Keywords: magnetite nanoparticles; lysozyme; protein immobilization