Background In molecular imaging and nuclear medicine, theranostic agents that integrate radionuclide pairs are successfully being used for individualized care, which has led to rapidly growing interest in their continued development. These compounds, which are radiolabeled with one radionuclide for imaging and a chemically identical or similar radionuclide for therapy, may improve patient-specific treatment and outcomes by matching the properties of different radionuclides with a targeting vector for a particular tumor type. One proposed theranostic radionuclide is scandium-47 ( 47 Sc, T 1/2 = 3.35 days), which can be used for targeted radiotherapy and may be paired with the positron emitting radionuclides, 43 Sc ( T 1/2 = 3.89 h) and 44 Sc ( T 1/2 = 3.97 h) for imaging. The aim of this study was to investigate the photonuclear production of 47 Sc via the 48 Ti(γ,p) 47 Sc reaction using an electron linear accelerator (eLINAC), separation and purification of 47 Sc, the radiolabeling of somatostatin receptor-targeting peptide DOTATOC with 47 Sc, and in vitro receptor-mediated binding of [ 47 Sc]Sc-DOTATOC in AR42J somatostatin receptor subtype two (SSTR2) expressing rat pancreatic tumor cells. Results The rate of 47 Sc production in a stack of natural titanium foils ( n = 39) was 8 × 10 7 Bq/mA·h ( n = 3). Irradiated target foils were dissolved in 2.0 M H 2 SO 4 under reflux. After dissolution, trivalent 47 Sc ions were separated from natural Ti using AG MP-50 cation exchange resin. The recovered 47 Sc was then purified using CHELEX 100 ion exchange resin. The average decay-corrected two-step 47 Sc recovery ( n = 9) was (77 ± 7)%. A radiolabeling yield of > 99.9% of [ 47 Sc]Sc-DOTATOC (0.384 mg in 0.3 mL) was achieved using 1.7 MBq of 47 Sc. Blocking studies using Octreotide illustrated receptor-mediated uptake of [ 47 Sc]Sc-DOTATOC in AR42J cells. Conclusions 47 Sc can be produced via the 48 Ti(γ,p) 47 Sc reaction and separated from natural Ti targets with a yield and radiochemical purity suitable for radiolabeling of peptides for in vitro studies. The data in this work supports the potential use of eLINACs for studies of photonuclear production of medical radionuc...

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