In Vivo PET/CT Imaging of Radiolabeled Peptides

For imaging studies, [⁶⁴Cu]1 and [⁶⁴Cu]2 (7.77–8.88 MBq) in PBS (100 μL, pH 7.2) were injected i.v. via a catheter into the tail vein of mice (n = 3/radiolabeled peptide) anesthetized with 2–3% isoflurane in medical grade oxygen. Animals were imaged in a prone position two at a time side by side. PET/CT scans were acquired using Inveon scanners (Inveon DPET scanner and Inveon SPECT/CT scanner, Siemens Medical Solutions, Knoxville, TN, USA; PET scans: a static 15 min scan at 4 h p.i., static 30 min scans at 24 and 48 h p.i., and a static 1 h scan at 72 h p.i.) and analyzed as previously described using the Inveon Research Workplace software (Siemens) [42 (link),44 (link)].