Fluorine-18: A radionuclide with diverse range of radiochemistry and synthesis strategies for target based PET diagnosis

Fluorine-18 is one of the most widely used radionuclides for the production of radiopharmaceuticals for positron emission tomography (PET). The radiolabeling methods like nucleophilic, electrophilic, Cu mediated mechanisms or prosthetic groups are widely using to achieve high regioselective radiochemical yields. It acts as a powerful tool to identify new drug targets through cellular uptake, pharmacokinetic (ADME) and pharmacodynamic parameters of the 18F labeled tracer or drug. These PET tracers have been developed based on the receptors expressed in a disease condition. A number of 18F radiotracers have been developed against the Tropomyosin Receptor Kinases (Trks), Carbonic anhydrases (CAs), Epidermal Growth Factor Receptors (EGFR), Poly ADP ribose polymerase (PARP) etc. for the diagnosis in cancer therapy. The current research also focused on the development of novel 18F radiotracers for neurological conditions for deciphering underlying physiology in diseases like Alzheimer, and Parkinson. Therefore, in this review we have focused on 18F labeling methods, and radiotracers developed against common cancers and neurological conditions. [Display omitted] •18F radiotracer is an ideal PET imaging agent due to its optimal half-life of 110 min.•The most common radiolabelling path is either nucleophilic or electrophilic radiofluorination.•Automated methods of radiolabelling have been developed using cGMP guidelines for clinical use.•Many tracers have been developed to image various receptors, uptakes, and pathways in the body.