Design of multifunctionalized γ-Fe 2 O 3 @SiO 2 core–shell nanoparticles for enzymes immobilization

Journal of Nanoparticle Research (Impact Factor: 2.28). 01/2010; 12(2):675-680. DOI: 10.1007/s11051-009-9757-0

ABSTRACT This article deals with the first covalent grafting of an enzyme on twice functionalized γ-Fe2O3@SiO2 core–shell magnetic nanoparticles. First, amino-PEG functionalized nanoparticles were synthesized in order to comply with
non-toxic platforms that would be stable in high concentration and would exhibit chemical groups to allow further coupling
with biomolecules. This approach produces a colloidal suspension of covalently grafted enzymes that remains stable for months
and mimics the enzyme–substrate interactions in solution. Secondly, nanoparticles synthesis and enzyme coupling process were
reported and the catalytic properties of bound enzymes were measured and compared with that of the free one. These new materials
appear to be useful tools for enzymatic catalysis research and may be extended to other biomolecules. Furthermore, magnetic
properties of these materials open the way to separation, purification, and transport under magnetic field.

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