Packard cobra 2 auto gamma counter

A full biodistribution was routinely conducted (blood, heart muscle, liver, kidneys, lungs, small intestine, brain, bladder, muscle, spleen, stomach, bone, tumor, and pancreas) after the last scan on day 8 (192 h). Organs were cleaned from blood, weighed and the activity determined using a γ-counter (Packard Cobra II auto-gamma counter, Perkin Elmer, Waltham, MA, USA). The calibration factor for 37 kBq of ⁶⁷Ga was 1 524 228 cpm (instrument specific). High activity organs (blood, liver) were measured in an Atomlab 500 dose calibrator (Biodex, Shirley, NY, US) if the activity exceeded 37 kBq. Total organ weights were used for the calculations of injected dose per organ (% ID per g organ) except for blood, liver, muscle, bone and pancreas, where average literature values were used.^{43–45 (link)}

After the last scan at day 6 (144 h), blood samples were collected by cardiac puncture, and a complete biodistribution assessment was conducted by collecting heart, liver, kidneys, lungs, lymph nodes (LNs), small intestine, bladder, muscle, site of injection, spleen, stomach, bone, trachea, and pancreas. The organs were cleaned from blood and weighed, and the radioactivity was measured using a gamma counter (Packard Cobra II autogamma counter, Perkin Elmer, Waltham, MA, USA). The calibration factor for ¹¹¹In was 163631 cpm and ⁶⁷Ga was 78395 cpm (instrument-specific). The total weight of the organs was used to calculate the administered dose per organ (%AD/organ).