In Vivo Chemistry for Pretargeted Tumor Imaging in Live Mice

Mice and men: An antibody conjugate with trans‐cyclooctene was administered to tumor‐bearing mice, and the resulting chemically tagged tumors were subsequently treated with an 111In‐labeled tetrazine probe in an inverse‐electron‐demand Diels–Alder reaction. The adduct was formed in a remarkable 52–57 % yield in vivo and used for non‐invasive pretargeted tumor imaging in mice (see picture).