Molecular Platform for Design and Synthesis of Targeted Dual-Modality Imaging Probes

Amit Kumar, Shanrong Zhang, Guiyang Hao, Gedaa Hassan, Saleh Ramezani, Koji Sagiyama, Su Tang Lo, Masaya Takahashi, A. Dean Sherry, Orhan K. Öz, Zoltan Kovacs, Xiankai Sun

Research output: Contribution to journalArticlepeer-review

19 Scopus citations


We report a versatile dendritic structure based platform for construction of targeted dual-modality imaging probes. The platform contains multiple copies of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) branching out from a 1,4,7-triazacyclononane-N,N′,N″-triacetic acid (NOTA) core. The specific coordination chemistries of the NOTA and DOTA moieties offer specific loading of 68/67Ga3+ and Gd3+, respectively, into a common molecular scaffold. The platform also contains three amino groups which can potentiate targeted dual-modality imaging of PET/MRI or SPECT/MRI (PET: positron emission tomography; SPECT: single photon emission computed tomography; MRI: magnetic resonance imaging) when further functionalized by targeting vectors of interest. To validate this design concept, a bimetallic complex was synthesized with six peripheral Gd-DOTA units and one Ga-NOTA core at the center, whose ion T1 relaxivity per gadolinium atom was measured to be 15.99 mM-1 s-1 at 20 MHz. Further, the bimetallic agent demonstrated its anticipated in vivo stability, tissue distribution, and pharmacokinetic profile when labeled with 67Ga. When conjugated with a model targeting peptide sequence, the trivalent construct was able to visualize tumors in a mouse xenograft model by both PET and MRI via a single dose injection.

Original languageEnglish (US)
Pages (from-to)549-558
Number of pages10
JournalBioconjugate Chemistry
Issue number3
StatePublished - Mar 18 2015

ASJC Scopus subject areas

  • Biotechnology
  • Bioengineering
  • Biomedical Engineering
  • Pharmacology
  • Pharmaceutical Science
  • Organic Chemistry


Dive into the research topics of 'Molecular Platform for Design and Synthesis of Targeted Dual-Modality Imaging Probes'. Together they form a unique fingerprint.

Cite this