Preparation and Kinetic Study of CoFe2O4@silica@ROL Nanobiocatalyst

Magnetic nanoparticles such as CoFe2O4, with their special properties such as higherspecific surface area for loading of a large amount of an enzyme, nontoxicity andbiocompatibility, and ease of separation from a reaction mixture applying a magnetic field areattractive substrate to immobilize lipase enzymes as extremely valuable biocatalysts for manypractical/industrial applications. Lipases have been used in pharmaceutical industry andproduction of fine chemicals and even biofuel. Employing lipases requires a full recycling ofthese enzymes to optimize economic benefits and minimize waste disposal for industrialpurposes which could be accomplished using magnetic nanoparticles as immobilizationsubstrates. Therefore, the aim of this work was to prepare silica coated magnetic substrates toimmobilize Rhizopus oryzae lipase (ROL) and study the kinetic parameters of this novel nanobiocatalyst. At first, CoFe2O4 nanoparticles were synthesized using a co-precipitation methodfollowed by coating with silica. Afterwards, the nanoparticles were functionalized with aminegroups. Lipase was then directly immobilized onto the modified nanoparticles through a covalentinteraction. Enzyme activity was assessed by measuring catalytic hydrolysis of p-nitrophenylbutyrate. The catalytic constant, kcat, and the catalytic efficiency, kcat/Km, increased 1.05 and0.854 times, respectively, after immobilization.

کلیدواژه ها:

Lipase ، CoFe2O4 Nanoparticle ، Nano Biocatalyst