Optimization of solid-phase extraction (SPE) in the preparation of [18F]D3FSP: A new PET imaging agent for mapping Aβ plaques

Alzheimer's disease is a common neurodegenerative disease that is characterized by the presence of Aβ plaques in the brain. The FDA has approved the use of Amyvid (florbetapir f18, AV-45) as a PET imaging agent for detecting Aβ plaques in the living human brain. In an attempt to reduce N-demethylation in vivo by taking advantage of more stable C-D bonds, an analog of AV-45, [¹⁸F]D3FSP ([¹⁸F]7), was synthesized to improve image contrast for detecting and monitoring the Aβ plaques. A convenient and improved preparation of [¹⁸F]D3FSP ([¹⁸F]7) is needed for widespread clinical application. We report herein the optimization of the radiosynthesis and solid-phase extraction (SPE) procedure.