Copper-free click - A promising tool for pre-targeted PET imaging

Comprehensive Cancer Imaging Centre, Department of Surgery & Cancer, Hammersmith Campus, Imperial College, London, United Kingdom.
Chemical Communications (Impact Factor: 6.83). 12/2011; 48(7):991-3. DOI: 10.1039/c1cc16220a
Source: PubMed


The copper-free click (CFC) reaction has been evaluated for its potential application to in vivo pre-targeting for PET imaging. A promising biodistribution profile is demonstrated when employing [(18)F]2-fluoroethylazide ([(18)F]1) and optimisation of the CFC reaction with a series of cyclooctynes shows that reactions proceed efficiently with tantalizing opportunities for application-specific tuning.

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Available from: Laurence Carroll
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    • "However, the need of cytotoxic copper during CuAAC has led to the necessity of alternative fast and copper-free click reaction strategies for radiofluorination and additionally enabling pretargeting approaches in living systems. Those so-called strain-promoted click reactions can be carried out between cyclooctyne derivatives and azides (strain-promoted azide-alkyne cycloaddition, SPAAC) [7] [8] [9] [10] [11] [12] [13] or tetrazines (tetrazine-trans-cyclooctyne (TTCO) ligation) [14] [15] [16] [17] as well as between norbornene derivatives and tetrazines [18]. Especially , the TTCO ligation showed promising reaction rates, which makes this click reaction concept very suitable for 18 Flabeling and also for in vivo application in living systems. "
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    • "Given their apparent high selectivity and promising rates of reaction in some cases, it is not surprising that SPAAC reactions have been considered as candidates to facilitate a pretargeting approach [130] [133] [134]. "
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    • "Copper is an essential trace element for all living organisms participating in various biological functions (Evans et al., 2012; Tisato et al., 2010) such as development, immune function, neovascularization processes, maintenance of neuroendocrine function and iron metabolism (O'Dell & Sunde, 1997). After iron and zinc, copper is the most abundant mineral in human body. "
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