Fabrication and characterization of glutathione-imprinted polymers on fibrous SiO₂ microspheres with high specific surface

The Glutathione (GSH)-imprinted thermosensitive SiO₂ microspheres with high specific surface have been successfully fabricated via a precipitation copolymerization, in which functional monomers N-isopropyl acrylamide and methacrylic acid polymerize on the surface of fibrous SiO₂ microspheres with N,N′-methylene bisacrylamide as cross-linking agent. Detailed characterization demonstrates that the SiO₂ microspheres not only possess fiber sphere-shaped structure with the pores radially extending outwards from the center, but also have outstanding surface area (521 m²/g) and relatively narrow pore size distribution ranging from 15 to 100 nm. Owing to this fibrous structure, the saturation adsorption capacity of the GSH-molecular imprinted polymer (MIP) microspheres reach up to 85 mg/g within 2 h, which is much higher than other the MIPs that have been reported. In addition, these microspheres also display an excellent selective adsorption of GSH (IF = 3.22). These results revealed that the fibrous SiO₂ microspheres could be expected as MIP carriers to separate and purify biomacromolecules.