Novel Magnetically Separable Mesoporous Fe2O3@SBA-15 Nanocomposite with Fully Open Mesochannels for Protein Immobilization

Magnetically separable Fe2O3@SBA-15 nanocomposite with fully open mesochannels and bifunctional surface properties was prepared by selective deposition of iron oxide nanoparticles in the micropores of mesoporous SBA-15 silica with hydrophobic mesopore surface. The iron oxide nanoparticles embedded in the micropores were estimated to be composed of 67% alpha-Fe2O3 and 33% gamma-Fe2O3, and the nanocomposite was found to exhibit superparamagnetic properties. With the bifunctional surface properties, the Fe2O3@SBA-15 nanocomposite showed enhanced adsorption capacity for cytochrome c and a maximum saturated uptake at neutral solution pH.