Recent Advances in ¹¹C-Labeling With [¹¹C]CO₂ for PET Imaging

Area of Science:

• Radiochemistry
• Nuclear Medicine
• Organic Synthesis

Background:

• Carbon-11 (¹¹C)-labeled radiotracers are essential for positron emission tomography (PET) imaging.
• Cyclotron-produced [¹¹C]CO₂ is a key precursor, but its reactivity and short half-life limit its synthetic applications.

Purpose of the Study:

• To review recent advancements in [¹¹C]CO₂ fixation chemistry.
• To evaluate the expanded utility of [¹¹C]CO₂ in synthesizing diverse radiolabeled compounds.
• To assess the potential for clinical translation of these new PET imaging agents.

Main Methods:

• Summary of nonphotocatalytic and photocatalytic methods for [¹¹C]CO₂ fixation.
• Analysis of substrate scope, radiochemical yield, and molar activity for various synthetic strategies.
• Evaluation of the clinical translation potential of newly developed PET agents.

Main Results:

• Significant progress in [¹¹C]CO₂ fixation chemistry has been achieved.
• New methods enable the synthesis of structurally diverse compounds like carboxylic acids, carbonates, carbamates, amides, and ureas.
• Advances enhance the synthetic versatility and expand the scope of PET imaging agent development.

Conclusions:

• Recent developments in [¹¹C]CO₂ chemistry have overcome previous limitations.
• These advancements facilitate the creation of a wider range of ¹¹C-labeled molecules for PET.
• The improved synthetic strategies pave the way for novel, clinically relevant PET imaging agents.