Sensitive and quantitative pEPR detection system for SPIO nanoparticles

A new system for the quantification of super paramagnetic iron oxide nanoparticles (SPIONs) is presented. The proposed system relies on the particle electron paramagnetic resonance (pEPR) technique and utilises the linear response of the SPIONs to generate a pEPR signal under a static field. By extracting the pEPR signals, whose intensity is proportional to the SPIONs concentration, the quantitative information of the SPIONs is derived. To evaluate the system performance, sensitivity measurements have been conducted with two commercial SPIONs, FeraSpin M and Resovist, and reveal a measurement sensitivity of 300 ng.