489427-26-1Relevant articles and documents
Radiopharmaceutical compositions
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, (2020/09/13)
The present invention relates to 99mTc-maraciclatide radiopharmaceutical compositions, which are stabilised with a radioprotectant. Also described are kits for the preparation of the radiopharmaceutical compositions, as well methods of preparin
Synthesis and in vitro and in vivo evaluation of SiFA-tagged bombesin and RGD peptides as tumor imaging probes for positron emission tomography
Lindner, Simon,Michler, Christina,Leidner, Stephanie,Rensch, Christian,W?ngler, Carmen,Schirrmacher, Ralf,Bartenstein, Peter,W?ngler, Bj?rn
, p. 738 - 749 (2014/05/06)
Gastrin-releasing-peptide (GRP)-receptors and ?± v?3-integrins are widely discussed as potential target structures for oncological imaging with positron emission tomography (PET). Favored by the overexpression of receptors on the surface of tumor cells good imaging characteristics can be achieved with highly specific radiolabeled receptor ligands. PEGylated bombesin (PESIN) derivatives as specific GRP receptor ligands and RGD (one-letter codes for arginine-glycine-aspartic acid) peptides as specific ?±v?3 binders were synthesized and tagged with a silicon-fluorine-acceptor (SiFA) moiety. The SiFA synthon allows for a fast and highly efficient isotopic exchange reaction at room temperature giving the [18F]fluoride labeled peptides in up to 62% radiochemical yields (d.c.) and a‰¥ 99% radiochemical purity in a total synthesis time of less than 20 min. Using nanomolar quantities of precursor high specific activities of up to 60 GBq ?mol-1 were obtained. To compensate the high lipophilicity of the SiFA moiety various hydrophilic structure modifications were introduced leading to significantly reduced logD values. Competitive displacement experiments with the PESIN derivatives showed a 32 to 6 nM affinity to the GRP receptor on PC3 cells, and with the RGD peptides a 7 to 3 ?M affinity to the ?± v?3 integrins on U87MG cells. All derivatives proved to be stable in human plasma over at least 120 min. Small animal PET measurements and biodistribution studies revealed an enhanced and specific accumulation of the RGD peptide 18F-SiFA-LysMe3-?- carboxy-d-Glu-RGD (17) in the tumor tissue of U87MG tumor-bearing mice of 5.3% ID/g whereas the PESIN derivatives showed a high liver uptake and only a low accumulation in the tumor tissue of PC3 xenografts. Stability studies with compound 17 provided further information on its metabolism in vivo. These results altogether demonstrate that the reduction of the overall lipophilicity of SiFA tagged RGD peptides is a promising approach for the generation of novel potent 18F-labeled imaging agents.
OPTICAL IMAGING
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Page/Page column 33, (2008/06/13)
This invention relates to a method for imaging of wet age-related macular degeneration (AMD) using a contrast agent comprising a vector attached to an optical imaging reporter, wherein the vector has affinity for receptors associated with angiogenesis. Th
IMAGING AGENTS WITH IMPROVED PHARMACOKINETIC PROFILES
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Page/Page column 14, (2010/02/15)
The invention relates to compounds suitable for use in an imaging agent said imaging agent showing an improved pharmacokinetic profile.