An imaging contrast composition comprising an iodinated contrast agent and a ligand secured to the iodinated contrast agent is disclosed, the ligand comprising a reactive group capable of bonding to a capture substrate. A method of removing iodinated radiocontrast agents from a patient is disclosed, the method comprising providing an iodinated radiocontrast agent containing a reactive group; providing a capture substrate for insertion into a patient's bloodstream; administering the iodinated radiocontrast agent to the patient; conducting procedure CT scan or procedure using fluoroscopy; and sequestering the iodinated radiocontrast agent on the capture substrate.