An increased uptake of vitamin B₁₂ has been observed in rapidly proliferating cells such as cancer cells. The functionalisation of vitamin B₁₂ with groups of diagnostic and/or therapeutic interes is a potential strategy to selectively deliver agents into tumor cells, to be exploited as contrast agents for MRI (Gd³⁺, ¹¹¹In³⁺) or for applications in neutron capture therapy (BNCT).

Transcobalamin Structure PNAS 2006, 103 (12), 4386		CNCbl-DTPA-Gd Chem. Eur. J. 2009, 15 (32), 7980