2.6. Biodistribution Studies

Biodistribution studies were performed after intravenous (i.v.) injection of the mice with [¹⁶¹Tb]Tb-DOTATOC or [¹⁷⁷Lu]Lu-DOTATOC (5 MBq; 1 nmol in 100 µL/mouse) diluted in PBS containing 0.05% bovine serum albumin. [¹⁶¹Tb]Tb-DOTA-LM3 or [¹⁷⁷Lu]Lu-DOTA-LM3 were used under the same conditions. The mice were sacrificed at 2 h and 24 h post injection (p.i.). Selected tissues and organs (blood, heart, lung, spleen, kidneys, adrenals, stomach, pancreas, intestines, liver, femoral muscle, femur, and tumor) were collected, weighed, and the accumulated activity was counted in a γ-counter. The decay-corrected data were listed as the percentage of the injected activity per gram of tissue mass (% IA/g).