Magnetic Particle Spectroscopy: A Short Review of Applications Using Magnetic Nanoparticles

Magnetic particle spectroscopy (MPS), also called magnetization response spectroscopy (MRS), is a versatile measurement tool derived from magnetic particle imaging (MPI). It can be interpreted as a zero-dimensional MPI scanner. MPS was primarily designed for characterizing superparamagnetic iron oxide nanoparticles (SPIONs) regarding their applicability for MPI. In recent years, it has evolved into an independent, versatile, highly sensitive, inexpensive platform for biological and biomedical assays, cell labeling and tracking, and blood analysis. MPS has also developed into an auxiliary tool for magnetic imaging and hyperthermia by providing high spatial and temporal mappings of temperature and viscosity. Furthermore, other MPS-based applications are being explored such as magnetic fingerprints for target tracking and identification. There are a variety of MPS-based applications being reported and demonstrated by many groups. In this short review, we highlight some of the representative applications based on the MPS platform, thereby providing a roadmap of this technology and our insights for researchers in this area.