ABSTRACT
The four main enzyme immobilization methods including adsorption or carrier binding, entrapment, covalent binding or cross-linking and membrane confinement have been used successfully in the last two decades. The enzyme immobilization methods take advantage of functional groups present in the side chain of amino acid. These amino acids bind with a carrier through various types of interactions including the weak bonds (ionic interaction, hydrogen bonds and Van der Waal forces) and covalent bonding. The nanomaterials-based immobilization have multiple advantages as compared to conventional immobilization techniques, such as easy synthesis in high solid loading, control over synthesis of particle size and homogeneity. Nanofibers have been used previously as enzyme carriers for the production of biofuels and bio products. The distinctive properties such as interconnectivity, porosity and easy separation of nanofibers make them good hosts for enzyme immobilization. Ethanol production was found to be increased when silica nanoparticles were used for physical adsorption of cellulose.
