Reactive oxygen species (ROS), including hydroxyl radicals, superoxide anions, and hydrogen peroxide, are produced within the mitochondria and various other electron transfer regions within cells. The overproduction of ROS has been linked to a wide range of health disorders such as cancer, heart disease, neurological disorders, and aging. Reliable sensors for non-invasive in vivo imaging of ROS not only provide an opportunity to monitor oxidative stress in vivo but can also facilitate the development of better treatment options. MRI is commonly used to non-invasively visualize internal tissues and organs. Biochemical processes can be monitored by MRI when a chemically responsive contrast agent is administered. Here, we have prepared a Mn(II) complex with the redox-active ligand 1,8-bis(2,5-dihydroxybenzyl)-1,4,8,11-tetraazacyclotetradecane (H4qp4) and characterized it as a redox-responsive MRI contrast agent. The Mn(II) compound reacts directly with H2O2 to yield a Mn(II) species with a 60% greater T1-related relaxivity (r1). The inclusion of a macrocycle in the ligand framework thermodynamically and kinetically stabilizes both the reduced and oxidized forms of the complex.

Synthesis and characterization of a more stable and more responsive MRI contrast agent sensor for hydrogen peroxide

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.