Peroxidase Sensitive Amplifiable Probe for Molecular Magnetic Resonance Imaging of Pulmonary Inflammation.

An amplifiable magnetic resonance imaging (MRI) probe that combines the stability of the macrocyclic Gd-DOTAGA core with a peroxidase-reactive 5-hydroxytryptamide (5-HT) moiety is reported. The incubation of the complex under enzymatic oxidative conditions led to a 1.7-fold increase in r1 at 1.4 T that was attributed to an oligomerization of the probe upon oxidation. This probe, Gd-5-HT-DOTAGA, provided specific detection of lung inflammation by MRI in bleomycin-injured mice.