Iron oxide nanoparticles demonstrate a number of unique properties, including superparamagnetism, biocompatibility, and non-toxicity, which make them an ideal candidate for a variety of applications, as described in this book. Chapter One deals with the recent advances in various synthetic procedures of iron oxide-based nanocomposites, their characterization methods, and their potential applications in energy storage devices, supercapacitors, fuel cells, and more. Chapter Two summarizes current applications of immobilized enzymes based on iron oxide magnetic nanoparticles and discusses future...