Magnetic Nanoparticles as Versatile Carriers for Immobilization of Laccase

Growing utilization of enzymes in different industries for bioremediation of xenobiotics encourages the search for high benefit/cost ratio immobilization techniques. Extremely simple procedures for the rapid preparation of magnetic nanoparticle enzyme carriers have been developed and used for the immobilization of laccase as model enzyme. In this study, magnetic nanoparticles (MNP) are used in order to obtain a versatile supporting material for enzyme immobilization. MNP size and morphologies were characterized by scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDAX). The magnetically separable nanoscaled enzyme catalysts show decreased masstransfer resistance and improved operational and storage stability. It should be emphasized that the main advantage of this versatile carrier is the possibility of its recovery with effective separation (even up to 5 s) from the reaction mixture with the use of magnet. This magnetic nanobiocatalyst rapidly decolorized 41-96 % of remazol brilliant blue R (RBBR) initially at 50 ppm at 20°C and pH 7.0, when 0.2 U/ml of magnetic laccase was used. UV-Vis spectroscopy analysis confirmed the biotransformation of dyes into several degraded products. The properties of magnetic nanobiocatalysts allow for better optimization and may reduce the total costs of the decolorization of dyes.