Representative radio–high-performance liquid chromatograms of plasma content at 8, 15, 60, and 120 min after intravenous injection of 18F-SynVesT-2 in humans, showing radiometabolite peaks with higher hydrophilicity (A), parent fraction of 18F-SynVesT-2 in plasma over time under baseline (n = 14) and blocking (n = 5) conditions (B), and concentration of 18F-SynVesT-2 (mean ± SD) in plasma over time under baseline (n = 14) and blocking conditions (n = 5) from 0 to 90 min after injection (C) and from 0 to 15 min after injection (D). HPLC = high-performance liquid chromatography.