New Ga-68-PhenA bisphosphonates as potential bone imaging agents

作者：Wu Zehui; Zha Zhihao; Choi Seok Rye; Plossl Karl; Zhu Lin; Kung Hank F^*

来源：Nuclear Medicine and Biology, 2016, 43(6): 360-371.

DOI：10.1016/j.nucmedbio.2016.03.002

• tumor
• gallium-68
• biodistribution
• PET imaging agents

Introduction: In vivo positron emission tomography (PET) imaging of the bone using [Ga-68]bisphosphonates may be a valuable tool for cancer diagnosis and monitoring therapeutic treatment. We have developed new [Ga-68] bisphosphonates based on the chelating group, AAZTA (6-[bis(hydroxycarbonyl-methyl)amino]-1,4-bis(hydroxycarbonyl methyl)-6-methylperhydro-1,4-diazepine).
Method: Phenoxy derivative of AAZTA (2,2'-(6-(bis(carboxymethyl)amino)-6((4-(2-carboxyethyl)phenoxy)methyl)-1,4-diazepane-1,4-diyl)diacetic acid), PhenA, 2, containing a bisphosphonate group (PhenA-BPAMD, 3, and PhenA-HBP, 4) was prepared. Labeling of these chelating agents with Ga-68 was evaluated.
Results: The ligands reacted rapidly in a sodium acetate buffer with [Ga-68]GaCl3 eluted from a commercially available Ge-68/Ga-68 generator (pH 4, >95% labeling at room temperature in 5 min) to form [Ga-68]PhenA-BPAMD, 3, and [Ga-68]PhenA-HBP, 4. The improved labeling condition negates the need for further purification. The Ga-68 bisphosphonate biodistribution and autoradiography of bone sections in normal mice after an iv injection showed excellent bone uptake.
Conclusion: New Ga-68 labeled bisphosphonates may be useful as in vivo bone imaging agents in conjunction with positron emission tomography (PET).

• 出版日期2016-6