Phosphonated near-infrared fluorophores for biomedical imaging of bone


H. Hyun, H. Wada, K. Bao, J. Gravier, Y. Yadav, M. Laramie, M. Henary, J. V. Frangioni, and H. S. Choi. 2014. “Phosphonated near-infrared fluorophores for biomedical imaging of bone.” Angewandte Chemie, 53, Pp. 10668-72.


The conventional method for creating targeted contrast agents is to conjugate separate targeting and fluorophore domains. A new strategy is based on the incorporation of targeting moieties into the non-delocalized structure of pentamethine and heptamethine indocyanines. Using the known affinity of phosphonates for bone minerals in a model system, two families of bifunctional molecules that target bone without requiring a traditional bisphosphonate are synthesized. With peak fluorescence emissions at approximately 700 or 800 nm, these molecules can be used for fluorescence-assisted resection and exploration (FLARE) dual-channel imaging. Longitudinal FLARE studies in mice demonstrate that phosphonated near-infrared fluorophores remain stable in bone for over five weeks, and histological analysis confirms their incorporation into the bone matrix. Taken together, a new strategy for creating ultra-compact, targeted near-infrared fluorophores for various bioimaging applications is described.


Hyun, HoonWada, HideyukiBao, KaiGravier, JulienYadav, YogeshLaramie, MattHenary, MagedFrangioni, John VChoi, Hak SooGermanyInternational ed. in EnglishAngew Chem Int Ed Engl. 2014 Sep 26;53(40):10668-72. doi: 10.1002/anie.201404930. Epub 2014 Aug 19.