Immobilization of Laccase on Functionalized Magnetic Nanoparticle: Enhanced Stability and Optimal pH for Catalytic Applications

Immobilization techniques are effective strategy to solve the problems associated with free enzymes in terms of improving the efficiency and stability of catalytic enzymes and increasing their separation and reusability in industrial applications. Magnetic nanoparticles are widely used in biomedical applications for the adsorption and separation of bioactive molecules and targeted drug delivery. Laccases are polycopper oxidases that degrade a wide range of phenolic and non-phenolic compounds and environmental pollutants. For this purpose, magnetic nanoparticles were synthesized using FeCl۲, FeCl۳ and ۳۰% NaOH, then coated with PVA and carboxyl-functionalized by succinic anhydride. The laccase enzyme was immobilized using NHS/EDC as a cross-linker and its efficiency was evaluated. The activities of free and immobilized enzymes were investigated between pH ۲.۲ and ۸. The findings showed that the immobilization efficiency of laccase was ۷۸% with an optimum pH of ۳ for both free and immobilized enzymes. The nanoparticles produced by immobilizing laccase retained their magnetic properties. Laccase was successfully immobilized on magnetic nanoparticles by covalent anchoring. The pH dependence of the immobilized laccase activities indicated that the enzyme became more stable after immobilization compared to the free form. The stabilized enzyme can be used to increase the efficiency of the industrial process.

کلیدواژه ها:

Immobilization ، Laccase ، Magnetic nanoparticle ، Polyvinyl alcohol