Evaluation of cyclotron production parameters for ⁴⁴Sc using Monte Carlo simulation

Area of Science:

• Nuclear Medicine
• Radiochemistry
• Medical Physics

Background:

• Scandium-44 (⁴⁴Sc) is a promising positron-emitting nuclide for theranostics, enabling co-labeling with therapeutic agents like ⁴⁷Sc and ¹⁷⁷Lu.
• Optimizing ⁴⁴Sc production is crucial for its clinical application in nuclear medicine.
• Monte Carlo simulations are essential for predicting nuclear reaction outcomes and optimizing experimental parameters.

Purpose of the Study:

• To optimize the production of scandium-44 (⁴⁴Sc) for theranostic applications.
• To simulate nuclear reaction processes and identify optimal experimental parameters for ⁴⁴Sc production.
• To investigate the impact of target thickness, proton energy, irradiation time, and cooling time on ⁴⁴Sc yield and purity.

Main Methods:

• Utilized the TALYS-2.0 program package to calculate nuclear reaction cross-sections.
• Employed the SRIM program to evaluate the stopping power of CaCO₃ targets for protons.
• Simulated nuclide production in a cyclotron using FLUKA to analyze experimental parameter influences.

Main Results:

• Thinner or thicker targets, compared to medium thickness, favor higher radionuclide purity of ⁴⁴Sc.
• Incident proton energies between 13-14 MeV yield higher ⁴⁴Sc activity.
• Optimal irradiation (8-12 hours) and cooling times (1-2 hours) enhance ⁴⁴Sc activity, purity, and reduce impurities like ¹³N and ¹⁸F.

Conclusions:

• The study successfully identified key parameters for optimizing ⁴⁴Sc production via simulation.
• Simulation results provide a reliable guide for experimentalists to achieve high-purity ⁴⁴Sc for theranostics.
• Calculations were validated against previous experimental data, confirming the accuracy of the simulation approach.