Gadolinium-based substances are materials that contain the chemical element gadolinium, which is a rare earth metal. These compounds are often used in medical imaging, particularly in magnetic resonance imaging (MRI), where they serve as contrast agents. Gadolinium helps enhance the clarity of images, allowing doctors to better visualize internal structures and diagnose conditions. In addition to medical applications, gadolinium-based materials are also utilized in various industrial processes and research. They can be found in electronics, nuclear reactors, and even in some types of magnets. Their unique properties make them valuable in both scientific and practical applications.