18F-fluoroparaaminobenzoic acid

18F-fluoroparaaminobenzoic acid (18F-PABA, also known as 2-[18F]fluoro-4-aminobenzoic acid or 18F-FPABA) is a fluorine-18 labeled small molecule radiotracer developed for positron emission tomography (PET) imaging of bacterial and fungal infections. It is a radiofluorinated analog of para-aminobenzoic acid (PABA), an essential precursor in the de novo folate biosynthesis pathway of prokaryotes and lower eukaryotes. 18F-PABA is selectively taken up by microorganisms and incorporated into folate via the enzyme dihydropteroate synthase (DHPS), which is absent in mammalian cells. This mechanism allows 18F-PABA to specifically accumulate in both Gram-positive and Gram-negative bacteria, as well as yeasts, enabling the noninvasive differentiation of active infections from sterile inflammation or cancer. Originally developed by researchers at Stony Brook University and Johns Hopkins University, 18F-PABA has also been evaluated and automated for clinical-scale synthesis by the University of Navarra and is being developed in collaboration with Chronus Pharmaceuticals.

Other names

18F-FPABA18F-PABA2-[18F]F-p-aminobenzoic acid2-[18F]fluoro-4-aminobenzoic acid2-[18F]fluoro-p-aminobenzoic acid2-[18F]fluoro-para-aminobenzoic acid[18F]F-PABA[18F]FPABA