Pretargeting Model

For the proof of concept of pretargeting in vivo a model described by Yazdani et al. was applied [20], based on TCO-modified alendronate for bone targeting. For preparation of TCO–alendronate, briefly, 20 mg sodium alendronate trihydrate (Sigma Aldrich) was dissolved in 400 µL 0.1N sodium-bicarbonate solution pH 8.5. Then 0.6 mL TCO–NHS ester (Click chemistry tools, Scottsdale, AZ, USA), 20 mg/mL in DMSO, were slowly added to the solution and stirred overnight in the dark, followed by freeze drying. As a control the same preparation was prepared, replacing TCO–NHS solution by the same volume of DMSO. For injection in mice the residue was dissolved in water and adjusted to pH 7 (30 mM).
