NanoArmoring of Enzymes by Polymer-Functionalized Iron Oxide Nanoparticles

Polymer-armored enzymes loaded onto magnetic nanoparticles, as efficient nanobioreactors with enhanced properties, are described in this chapter. Polymers are useful macromolecules carrying a large number of surface charges and repeating units of desired chemical functional groups for linking enzymes onto them. Magnetic micro/nanoparticles have been widely used as enzyme carriers with the incorporation of suitable polymer layers. Synthesized iron oxide magnetic nanoparticles have been used to immobilize a peroxide-catalyzing enzyme-like heme protein: myoglobin using covalent and noncovalent strategies. The stability, scalability, and kinetics of the conjugate were studied in detail using spectroscopic and electrochemical analysis. Compared to the free myoglobin in solution, myoglobin conjugated to magnetic nanoparticles demonstrated high catalytic stability and easy recovery from the reaction medium for further use. Due to the large surface area offered by the magnetic nanoparticles, a large amount of myoglobin could be loaded with a small amount of magnetic nanoparticles. Selected examples of polymer-enzyme and polymer-magnetic nanoparticle-enzyme conjugates developed by us and others are presented in this chapter, and representative methods for making cost-effective scalable and reusable enzymatic reactors have been described.