Abstract
Biocompatible magnetic nanosensors have been designed to detect molecular interactions in biological media. Upon target binding, these nanosensors cause changes in the spin-spin relaxation times of neighboring water molecules, which can be detected by magnetic resonance (NMR/MRI) techniques. These magnetic nanosensors have been designed to detect specific mRNA, proteins, enzymatic activity, and pathogens (e.g., virus) with sensitivity in the low femtomole range (0.5-30 fmol).