Superparamagnetic iron oxide--myoglobin as potential nanoparticle: iron oxide--myoglobin binding properties and magnetic resonance imaging marker in mouse imaging

Superparamagnetic iron oxide (Fe2O3) has emerged as a potential MRI contrast agent in whole animal imaging. We achieved initial success in binding superparamagnetic iron oxide with myoglobin antibody (SPIOM) in order to develop it as a possible MRI contrast agent. In this paper, we highlight the binding properties of iron oxide with myoglobin and their pH dependence shown by Raman spectroscopy and MRI imaging. The use of iron oxide--myoglobin superparamagnetic particles as a contrast agent was developed in order to visualize its myoglobin distribution within a mouse heart using MRI imager at 11.7 Tesla. To validate the MRI visualization, the MRI imaging of iron-oxide bound myoglobin SPIOM phantom was carried out using capillaries filled with contrast agent at pH 7 and pH 4. The MRI imaging can serve as a reference to measure the density distribution of myoglobin at different SPIOM concentrations in the mouse's body, especially its heart and blood vessels. We report the technical details of SPIOM and its possible use in MRI as a tool for visualizing mice heart and myocardium.