Production and modeling of radioactive gold nanoparticles in Tehran research reactor

Production and characterization of 111Ag radioisotope for medical use in a TRIGA Mark II nuclear research reactor

Radio Pharmaceutical Therapy (RPT) comes forth as a promising technique to treat a wide range of tumors while ensuring low collateral damage to nearby healthy tissues. This kind of cancer therapy exploits the radiation following the decay of a specific radionuclide to deliver a lethal dose to tumor tissues. In the framework of the ISOLPHARM project of INFN, ¹¹¹Ag was recently proposed as a promising core of a therapeutic radiopharmaceutical. In this paper, the production of ¹¹¹Ag via neutron activation of ¹¹⁰Pd-enriched samples inside a TRIGA Mark II nuclear research reactor is studied. The radioisotope production is modeled using two different Monte Carlo codes (MCNPX and PHITS) and a stand-alone inventory calculation code FISPACT-II, with different cross section data libraries. The whole process is simulated starting from an MCNP6-based reactor model producing the neutron spectrum and flux in the selected irradiation facility. Moreover, a cost-effective, robust and easy-to-use spectroscopic system, based on a Lanthanum Bromo-Chloride (LBC) inorganic scintillator, is designed and characterized, with the aim of using it, in the future, for the quality control of the ISOLPHARM irradiated targets at the SPES facility of the Legnaro National Laboratories of INFN. ^natPd and ¹¹⁰Pd-enriched samples are irradiated in the reactor main irradiation facility and spectroscopically characterized using the LBC-based setup and a multiple-fit analysis procedure. Experimental results are compared with theoretical predictions of the developed models, showing that inaccuracies in the available cross section libraries prevent an accurate reproduction of the generated radioisotope activities. Nevertheless, models are normalized to our experimental data allowing for a reliable planning of the ¹¹¹Ag production in a TRIGA Mark II reactor.

Study of the 199Au nanoparticles production parameters via irradiation of platinum target by using thermal neutrons

In this study, the production parameters of ¹⁹⁹Au nanoparticles (¹⁹⁹AuNPs) have been investigated by a two-part study. The first part is about investigating the indirect method of producing non-carrier-added (NCA) ¹⁹⁹Au radionuclide. MCNPX-2.6, TALYS-1.9, and ALICE/ASH-0.1 codes were applied as the theoretical approach to simulate the core of Tehran research reactor (TRR) for determining the activity of ¹⁹⁹Au, specifying the production yield of ¹⁹⁹Au, and calculating the excitation function of P198t(n,γ)P199t→A199u reaction. As the corresponding experimental approach, two 11 mg and 15.5 mg samples of enriched ¹⁹⁸Pt metal powder were irradiated by thermal neutrons for 21 h and 10 min. The liquid-liquid extraction (LLX) technique has been used with a different solvent for each sample. LLX using ethyl acetate and LLX using Di-(2-Ethylhexyl) phosphoric acid (HDEHP) were applied for the 15.5 mg and the 11 mg samples respectively. The chemical yield of ¹⁹⁹Au was calculated more than %99 for the 15.5 mg sample, and more than %80 for the 11 mg sample. The second part is about synthesizing ¹⁹⁹AuNPs in an average size of 50 nm by using Turkevich method.

Radioactive gold nanocluster (198-AuNCs) showed inhibitory effects on cancer cells lines

Cancer is a global epidemic disease responsible for over ten millions death worldwide. The early diagnosis and the precise treatment with reduced adverse reactions are the main goal worldwide. In this study, we produced, characterized and evaluated (in vitro) in three different cancer cell lines (protaste, breast and melanoma) a radioactive gold nanocluster (R-AuNC) (¹⁹⁸Au25(Capt)18). The pharmacokinetics as the influence in the ABC transporter (MRP1 Efflux Transporter Protein) was also evaluated. The results showed that R-AuNC (¹⁹⁸Au25(Capt)18) are capable to kill the cancer cells lines of protaste, breast and melanoma. The pharmacokinetics showed a fast clearance and great volume of distribution, confirming the use of R-AuNC as nanomedicine for cancer treatment. Finally, the ABC transporter assay corroborated that the R-AuNC (¹⁹⁸Au25(Capt)18) has no risk of being pumped out of cells by this efflux transporter. The results validate the use of gold nanoparticles as therapeutic nanomedicine for cancer treatment.

Radiolabeled Gold Nanoparticles for Imaging and Therapy of Cancer

In the Last decades, nanotechnology has provided novel and alternative methodologies and tools in the field of medical oncology, in order to tackle the issues regarding the control and treatment of cancer in modern society. In particular, the use of gold nanoparticles (AuNPs) in radiopharmaceutical development has provided various nanometric platforms for the delivery of medically relevant radioisotopes for SPECT/PET diagnosis and/or radionuclide therapy. In this review, we intend to provide insight on the methodologies used to obtain and characterize radiolabeled AuNPs while reporting relevant examples of AuNPs developed during the last decade for applications in nuclear imaging and/or radionuclide therapy, and highlighting the most significant preclinical studies and results.

Production assessment of non-carrier-added 199Au by (n,γ) reaction

Gold-199 is a promising theranostic radionuclide for targeted radioimmunotherapy as well as for scintigraphy and dosimetry. ¹⁹⁹Au can be produced in two methods in the direct and indirect routes of the reactor production via ¹⁹⁷Au(n,γ)¹⁹⁸Au(n,γ)¹⁹⁹Au as the direct or ¹⁹⁸Pt(n,γ)¹⁹⁹Pt→¹⁹⁹Au as the indirect method. This investigation described the development of a method for the reactor production of no-carrier-added (NCA) ¹⁹⁹Au through neutron activation of natural Pt in Tehran Research Reactor (TRR) at a thermal neutron flux of 3.5 × 10¹³ n cm^-2 s^-1. Also, in this paper, the activity of ¹⁹⁹Au has been estimated using the MCNPX code. In this case, first, the reactor core is simulated. Then the calculated results are compared with the corresponding experimental values. Moreover, two different chemical separation methods are investigated experimentally in details.

Assessment and estimation of 65Zn production yield via neutron induced reaction on natZnO and natZnONPs

Zinc-65 has been of great interest in medical, biomedical, agricultural, and industrial applications due to its suitable half-life and decay properties. The ⁶⁵Zn was produced via neutron irradiation on natural zinc oxide and natural zinc oxide nanoparticles targets in Tehran Research Reactor (TRR) at a thermal neutron flux of 4.5 × 10¹³ n cm^-2 s^-1 for 30 min. The excitation function of ⁶⁴Zn(n,γ)⁶⁵Zn reaction was calculated via the TALYS-1.8 code. The MCNPX code was used to calculate the thermal neutron distribution. The ⁶⁵Zn theoretical production yield was estimated using calculated cross sections and the calculated thermal neutron distribution. The obtained experimental data and simulated value of production yield for ⁶⁵Zn were in reasonable agreement.

64Cu, a powerful positron emitter for immunoimaging and theranostic: Production via natZnO and natZnO-NPs

⁶⁴Cu is one of the most beneficial radionuclide that can be used as a theranostic agent in Positron Emission Tomography (PET) imaging. In this current work, ⁶⁴Cu was produced with zinc oxide nanoparticles (^natZnONPs) and zinc oxide powder (^natZnO) via the ⁶⁴Zn(n,p)⁶⁴Cu reaction in Tehran Research Reactor (TRR) and the activity values were compared with each other. The theoretical activity of ⁶⁴Cu also was calculated with MCNPX-2.6 and the cross sections of this reaction were calculated by using TALYS-1.8, EMPIRE-3.2.2 and ALICE/ASH nuclear codes and were compared with experimental values. Transmission Electronic Microscopy (TEM), Scanning Electronic Microscopy (SEM) and X-Ray Diffraction (XRD) analysis were used for samples characterizations. From these results, it's concluded that ⁶⁴Cu activity value with nanoscale target was achieved more than the bulk state target and had a good adaptation with the MCNPX result.

Experimental study and simulation of 63Zn production via proton induce reaction

The ⁶³Zn was produced by16.8 MeV proton irradiation of natural copper. Thick target yield for ⁶³Zn in the energy range of 16.8 →12.2 MeV was 2.47 ± 0.12 GBq/μA.h. Reasonable agreement between achieved experimental data and theoretical value of thick target yield for ⁶³Zn was observed. A simple separation procedure of ⁶³Zn from copper target was developed using cation exchange chromatography. About 88 ± 5% of the loaded activity was recovered. The performance of FLUKA to reproduce experimental data of thick target yield of ⁶³Zn is validated. The achieved results from this code were compared with the corresponding experimental data. This comparison demonstrated that FLUKA provides a suitable tool for the simulation of radionuclide production using proton irradiation.

Assessment and estimation of 67Cu production yield via deuteron induced reactions on natZn and 70Zn

⁶⁷Cu radioisotope is a beta particle-emitting nuclide used in radioimmunotherapy (RIT) as well as for imaging, tracer kinetic studies and dosimetry. ⁶⁷Cu can be produced by bombarding ^natZn with deuterons. In this study, the physical yields of ⁶⁷Cu via ^natZn(d,x)⁶⁷Cu reaction channel as well as via subreactions of ⁶⁸Zn(d,2pn)⁶⁷Cu, ⁶⁷Zn(d,2p)⁶⁷Cu, ⁷⁰Zn(d,2p3n)⁶⁷Cu, ⁶⁸Zn(d,x)⁶⁷Ni(T_1/2=21s)→⁶⁷Cu and ⁷⁰Zn(d,x)⁶⁷Ni(T_1/2=21s)→⁶⁷Cu in the ^natZn target have been calculated by using the MCNPX-2.6, TALYS-1.8 and SRIM codes. Also, the total cross sections for production of ⁶⁷Cu from ^natZn(d,x)⁶⁷Cu reaction channel in the energy range of 15-45MeV have been estimated by TALYS code. The best reaction to produce ⁶⁷Cu radionuclide in a carrier free form was chosen with deuteron energy around 30MeV on ⁷⁰Zn thick target. Good agreement between the calculated results and the experimental values shows that the employed methods can be used for prediction and production estimation in cyclotron.