Abstract
Sustainable generation of biofuels is gaining substantial attraction as an alternative for substitution of petrochemical-derived products, which allows to mitigate common problems caused by the overuse of fossil fuels, such as global warming and climate change. The integration of nanotechnology and biotechnology brings a bright future in the energy sector. By the application of nanobiocatalysis, it is possible to support efficient reactions with high stability, improving the overall fuel yields. Enzymatic biocatalysis is a highly efficient and widely employed procedure in biotechnological applications due to the biodegradable nature of enzymes. However, lack of stability, high cost of operability, hard recovery and non-reusable ability are among the most critical and challenging aspects, which can be solved by the immobilization of enzymes in nanostructured materials, leading towards the development of a nanobiocatalyst. As one of the most promising nanostructured materials as versatile carriers for enzyme immobilization, magnetic nanoparticles (MNPs) have gained special attention due to its important characteristics, including high specific area, elevated enzyme loading ability, controllable particle size, modifiable surface, and most importantly, easily, and rapid separation from solutions by applying and external magnetic field. It has been reported that surface coating or modification of MNPs with a variety of complex materials, such as polymers, silica, metallic-organic frameworks (MOFs), and carbon-based materials, might allow to improve some properties and provide potential industrial exploitability. Thus, the different steps to be considered at the time to design a proper magnetic nanobiocatalyst are reviewed, including routes of synthesis, surface modification and immobilization techniques. Moreover, this work will present the role of MNPs for enhancing biofuels production, such as biodiesel, bioethanol, biohydrogen and biogas; and how nanobiocatalysts may allow improving the performance of these bioprocesses.