Particles comprising bilirubin derivative and metal

A bilirubin chelate complex comprising:

• a plurality of bilirubins each conjugated with a hydrophilic molecule;
• and
• a metal nanoparticle attached by coordinate bonds to at least one of a carboxyl group, a lactam group, or a pyrrole ring of the bilirubin,
• wherein the bilirubin chelate complex has a shell-core shape comprising a shell formed by the plurality of bilirubins, and the hydrophilic molecule conjugated with each of the plurality of bilirubins extends from the shell,
• wherein the metal nanoparticle comprises a superparamagnetic iron oxide nanoparticle (SPION) or a gold nanoparticle;
• and
• wherein the metal nanoparticle is enclosed within the core, and the metal nanoparticle enclosed within the core is in the form of a single metal particle.

A bilirubin chelate complex comprising:

• a plurality of bilirubins each conjugated with a hydrophilic molecule;
• and
• a metal nanoparticle attached by coordinate bonds to at least one of a carboxyl group, a lactam group, or pyrrole ring of the bilirubin,
• wherein the bilirubin chelate complex has a shell-core shape comprising a shell formed by the plurality of bilirubins, and the hydrophilic molecule conjugated with each of the plurality of bilirubins extends from the shell,
• wherein the metal nanoparticle comprises a superparamagnetic iron oxide nanoparticle (SPION) or a gold nanoparticle;
• and
• wherein the metal nanoparticle is enclosed within the core, and the metal nanoparticle enclosed within the core is in the form of clustered metal particles.