Collagen‐Targeted MRI Contrast Agent for Molecular Imaging of Fibrosis

A cyclic peptide specific for type I collagen is derivatized with three {Gd(dtpa)} moieties to create a molecular MRI contrast agent for fibrosis imaging. In a mouse model of myocardial infarction (heart attack), collagen levels are elevated in the infarct zone. MRI after injection of the contrast agent selectively enhances and delineates the infarct zone (see preinjection and postinjection images); dtpa=diethylenetriaminepentaacetate.