Nanomaterials possess enormous potential for biomedical applications, while some of the most promising nanomaterials currently under investigation demonstrate prolonged tissue retention and contain heavy metals. This article investigates the pharmacokinetics of magnetic nanoparticles (MNPs) to help identify promising candidates with optimal pharmacokinetics and clearance from the body for biomedical use and synthesize nanomaterials ideal for biomedical use. The term 'magnetic nanoparticles' (MNPs) refers to nanoparticles with ferromagnetism. Such nanoparticles have special characteristics, and many in the field of biological field have undertaken research involving, e.g., immobilized enzymes and proteins, biological cells, macromolecular separation, drug carriers, and targeted, immune, biological sensors.