Fluorine-18 labeling methods: Features and possibilities of basic reactions

Area of Science:

• Nuclear chemistry
• Radiopharmaceutical science
• Medical imaging

Background:

• Fluorine-18 (18F) is the most utilized radionuclide in positron emission tomography (PET) due to its favorable decay properties.
• There is a continuous and growing need for improved and simplified 18F-labeling strategies to meet clinical demands.

Purpose of the Study:

• To provide a comprehensive overview of 18F-labeling methodologies.
• To highlight advancements in radiofluorination techniques for PET tracer development.
• To introduce specific applications and strategic concepts in 18F radiopharmaceutical synthesis.

Main Methods:

• Review of established and novel radiofluorination methods.
• Description of direct electrophilic and nucleophilic 18F-labeling processes.
• Discussion of indirect synthesis strategies using synthons and prosthetic groups.
• Focus on radiofluorination of arenes, particularly using iodonium leaving groups.

Main Results:

• Detailed explanation of the advantages and production routes of fluorine-18.
• Elucidation of the principles behind various 18F-labeling techniques.
• Illustrative examples of radiopharmaceutical syntheses using strategic labeling concepts.

Conclusions:

• The review covers essential aspects of 18F-labeling, from basic principles to advanced applications.
• Progress in no-carrier-added 18F-labeling procedures is emphasized.
• The presented strategies are vital for the development of new PET imaging agents.