Separation of 44Sc from Natural Calcium Carbonate Targets for Synthesis of 44Sc-DOTATATE

Abstract

The rapid increase in applications of scandium isotopes in nuclear medicine requires new efficient production routes for these radioisotopes. Recently, irradiations of calcium in cyclotrons by α, deuteron, and proton beams have been used. Therefore, effective post-irradiation separation and preconcentration of the radioactive scandium from the calcium matrix are important to obtain the pure final product in a relatively small volume. Nobias resin was used as a sorbent for effective separation of 44Sc from calcium targets. Separation was performed at pH 3 using a column containing 10 mg of resin. Scandium was eluted with 100 μL of 2 mol L−1 HCl. Particular attention was paid to the reduction of calcium concentration, presence of metallic impurities, robustness and simple automation. 44Sc was separated with 94.9 ± 2.8% yield, with results in the range of 91.7–99.0%. Purity of the eluate was confirmed with ICP-OES determination of metallic impurities and >99% chelation efficiency with DOTATATE, followed by >36 h radiochemical stability of the complex. A wide range of optimal conditions and robustness to target variability and suspended matter facilitates the proposed method in automatic systems for scandium isotope separation and synthesis of scandium-labeled radiopharmaceuticals.

Separation of 44Sc from 44Ti in the Context of A Generator System for Radiopharmaceutical Purposes with the Example of [44Sc]Sc-PSMA-617 and [44Sc]Sc-PSMA-I&T Synthesis

“…Considering the published results on the successful extraction of n.c.a. scandium radionuclides ( 43,44,47 Sc) using chelating resins Chelex 100 [13,[29][30][31] and NOBIAS Chelate-PA1 [32], as well as our results on the efficient isolation of medical radionuclides from oxalate solutions with Chelex 100 (e.g., 89 Zr [33]), this type of resin has also been tested for the recovery of scandium-44 from the generator eluate.…”

Development of an Automatic Column Chromatography Separation Device for Metal Isotope Analysis Based on Droplet Counting

“…Several automated chromatography separation systems have been developed to reduce the personnel workload. − In fact, automated methods have long been successfully established and adopted in fields of traditional stable isotope analysis. − In recent years, the development and adoption of similar methods for radiogenic and non-traditional stable isotopes have also been developed, − where the eluent is controlled by a peristaltic pump or syringe pump. Among these pump-based systems, the commercialized fully automated ion exchange chromatography system prepFAST-MC (ESI, Omaha, NE, USA) has received increasing interest.…”

Selective separation of no carrier added Sc-47 from reactor irradiated Ca using zirconium vanadate gel for nuclear medical applications

“…Despite the physical and nuclear properties of 47 Sc, which refers to its potential to be used as a theragnostic agent, there are different factors that hindered the production of 47 Sc, such as the high cost of the enriched target [7]. Several separation methods have been performed on the irradiated natural calcium target to achieve a high separation yield for 47 Sc with high radiochemical, radionuclidic and chemical purity based on solvent extraction such as tributyl phosphate [11] and ion exchange technique using different exchangers [12][13][14][15][16][17][18][19][20][21][22]. Synthetic inorganic ion exchangers are still more widely used due to their substantial advantages over organic resins [23,24].…”