Abstract: Described herein are compositions having a nanoparticle that is conjugated to at least one bone targeting moiety, wherein the bone targeting moiety is bonded to the nanoparticle by a linker, wherein the nanoparticle contains iron, and wherein the compositions are neutral or pharmaceutically acceptable salts or esters. Also described herein are methods of making these compositions. In one aspect, the nanoparticles serve as contrast agents for magnetic resonance imaging of bone metabolism. The compounds, compositions, and methods described herein can be used in a number of therapeutic applications including diagnosing or monitoring fracture and/or the progress of conditions associated with bone loss, which include, but are not limited to, osteoporosis, Paget's disease, osteolytic tumors, rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, osteoarthritis, osteopenia, and hypercalcemia.

Abstract: Described herein is insulin, an insulin-like growth factor, parathyroid hormone, a fragment of parathyroid hormone, or a parathyroid hormone related protein that includes at least one bone targeting moiety, wherein the bone targeting moiety is covalently bonded to the peptide. Also described herein are the methods of making these compositions that prevent or treat conditions associated with bone loss and preventing bone fractures, and/or the inability to initiate de novo bone turnover and stimulate bone fracture repair.

Abstract: Described herein are compositions having a nanoparticle that is conjugated to at least one bone targeting moiety, wherein the bone targeting moiety is bonded to the nanoparticle by a linker, wherein the nanoparticle contains iron, and wherein the compositions are neutral or pharmaceutically acceptable salts or esters. Also described herein are methods of making these compositions. In one aspect, the nanoparticles serve as contrast agents for magnetic resonance imaging of bone metabolism. The compounds, compositions, and methods described herein can be used in a number of therapeutic applications including diagnosing or monitoring fracture and/or the progress of conditions associated with bone loss, which include, but are not limited to, osteoporosis, Paget's disease, osteolytic tumors, rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, osteoarthritis, osteopenia, and hypercalcemia.

Abstract: Described herein is insulin, an insulin-like growth factor, parathyroid hormone, a fragment of parathyroid hormone, or a parathyroid hormone related protein that includes at least one bone targeting moiety, wherein the bone targeting moiety is covalently bonded to the peptide. Also described herein are the methods of making these compositions that prevent or treat conditions associated with bone loss and preventing bone fractures, and/or the inability to initiate de novo bone turnover and stimulate bone fracture repair.