Zirconium-based Material Research Articles

Characterization of Zirconium-Based Material (ZBM) Synthesized by Gradual Drying for Molybdenum-99 (99Mo) Adsorbent

Technetium-99m (99mTc), the daughter radionuclide of Molybdenum-99 (99Mo), is the most widely used radionuclide in the world and predicted to face a shortage in the future. A Zirconium-based material(ZBM) is an alternative solution to overcome this problem due to its high adsorption capacity toward 99Mo, and ability to release 99mTc. The performance of the ZBM is influenced by its material properties, especially the surface area and pore diameter. This study aims to characterize and evaluate the ZBM developed by new synthesis method. The ZBM was synthesized using zirconium(IV) chloride, 2-propanol, water and tetrahydrofuran. The drying process after synthesis was conducted by gradual heating. The resulting material was analysed by XRD, SEM, and BET method. The 99Mo adsorption and 99mTc releasing capacity was also evaluated. The analysis result shows that the ZBM is an amorphous material, while its surface area, pore volume, and pore diameter was 45.8 m2/g, 0.19 cm3/g, and 16.29 nm, respectively. The 99Mo adsorption, and 99mTc releasing capacity of the ZBM was 181.58 mg Mo/g ZBM, and 91.81%, respectively.

Influence of GA Siwabessy Reactor Irradiation Period on The Molybdenum-99 (99Mo) Production by Neutron Activation of Natural Molybdenum to Produce Technetium-99m (99mTc)

Production of 99Mo by neutron activation of natural Mo in multipurpose reactor GA Siwabessy is an alternative solution to overcome the 99Mo shortage, particularly in Indonesia. The aim of this study is to evaluate the influence of the irradiation period of the reactor on the quality of the produced 99Mo and 99mTc. A natural molybdenum was packed in quartz ampule and aluminium capsule, irradiated in the research reactor for around 100 hours. The 99Mo - 99mTc separation was conducted in Center for Radioisotope and Radiopharmaceutical Technology using zirconium-based material (ZBM). The observed parameters are 99Mo activity, 99mTc yield percentage, adsorption capacity ZBM and 99mTc quality. Both the obtained 99Mo activity and 99mTc yield percentage were influenced by the irradiation period. On the other hand, neither the adsorption capacity of ZBM nor quality parameters of 99mTc were influenced by the irradiation period.

Influence Of Drying Time And Temperature On Zirconium-Based Material (ZBM) Properties For 99Mo/99mTc Generator Development

Zirconium-based material (ZBM) has an important role in producing Technetium-99m (99mTc) due to its high adsorption capacity to Molybdenum-99 (99Mo). The adsorption capacity of the ZBM depends on the specific surface area which is influenced by several parameters in the synthesis process. This study aims to investigate the influence of drying time and temperature on the structure and specific surface area of the ZBM. Synthesis of the ZBM was carried out using zirconium chloride, 2-propanol, water and tetrahydrofuran at 75 °C, 90 °C and 120 °C and for 3 hr, 5 hr and 7 hr, respectively. Functional group and specific surface area of the ZBM was analyzed by FTIR and BET method, respectively. At the variation of drying time, the functional group pattern showed by FTIR spectra was not significantly different. The O-H group of the ZBM increased as the drying temperature decreases. At 75 and 90°C, the specific surface area increased as the function of time was increased but was decreased at 120°C. The highest surface area of the synthesized ZBM had a poor performance as a 99Mo/99mTc generator material, whereas the eluate met the required standard.

Development of <sup>99</sup>Mo/<sup>99m</sup>Tc Generator System for Production of Medical Radionuclide <sup>99m</sup>Tc using a Neutron-activated <sup>99</sup>Mo and Zirconium Based Material (ZBM) as its Adsorbent

Molybdenum produced from fission of U-235 is the most desirable precursor for 99 Mo/ 99m Tc generator system as it is non-carrier added and has high specific activity. However, in the last decade there has been short supply of 99 Mo due to several constrains. Therefore, there have been many works performed for development of 99 Mo/ 99m Tc generator system using 99 Mo which is not produced from either LEU or HEU. This report deals with development of 99 Mo/ 99m Tc generator system where zirconium-based material (ZBM) is used as adsorbent of neutron-activated 99 Mo. The system was prepared by firstly irradiating natural Mo in the G. A. Siwabessy reactor to produce neutron-activated 99 Mo. The target was dissolved in NaOH 4N and then neutralized with 12 M HCl. The 99Mo solution was then mixed with a certain amount of ZBM followed by heating at 90°C for three hours to allow the 99Mo adsorbed on ZBM. The 99Mo-ZBM (9.36 GBq of 99 Mo was Mo/ 4.2 g ZBM) was packed on a fritz-glass column. This column was then fitted serially with an alumina column for trapping 99 Mo breakthrough. The columns were then eluted daily with saline solution for up to one week. The yield of 99m Tc was found to be between 53.7 – 74% (n= 5). All 99m Tc eluates were clear solutions with pH of 5. Breakthrough of 99 Mo in 99m Tc eluates was found to be 0.031 ± 0.019 μCi 99 Mo/ mCi 99m Tc (n= 5) which was less than the maximum activity of 99 Mo allowed in 99m Tc solution (< 1 µCi 99 Mo/mCi 99m Tc). Aluminum breakthrough in 99m Tc eluates was found to be less than 10 ppm. The radiochemical purity of 99m Tc in form of Na 99m TcO 4 was > 99%. Radiolabeling of this 99m Tc towards methylene diphosphonate (MDP) kit gave a radiolabelling efficiency of 99%. In summary, a new 99 Mo/ 99m Tc generator system that used neutron-activated 99 Mo and ZBM as its adsorbent has been successfully prepared. The 99m Tc produced from this new 99 Mo/ 99m Tc generator system attained the quality of 99m Tc required for medical purposes. Received: 23 Februari 2016; Revised: 13 July 2016; Accepted: 17 July 2016

The Use of Sodium Hypochlorite Solution for (n,γ)<sup>99</sup>Mo/<sup>99m</sup>Tc Generator Based on Zirconium-Based Material (ZBM)

The many problems in preparing fission product 99 Mo led into this work to develop 99 Mo/ 99m Tc generator using neutron-irradiated natural MoO 3 targets and, more specifically, to develop a zirconium-based material (ZBM) for chromatography columns that have an adsorption capacity of more than 100 mg Mo/g ZBM. This paper reports our recent experiments in the use of sodium hypochlorite solution of various concentrations to improve the yield of 99m Tc in performance of (n,γ) 99 Mo/ 99m Tc generators based on the ZBM. The synthesized ZBM was coated with tetraethyl orthosilicate for improving the hardness of the material. The adsorption of [ 99 Mo]molybdate into ZBM was carried out by reacting ZBM into [ 99 Mo]molybdate solution at 90 ° C to form ZBM-[ 99 Mo] molybdate. ZBM-[ 99 Mo]molybdate was then packed into generator column, then eluted with 10 × 1 mL of saline followed by 1 × 5 mL of NaOCl solution. The NaOCl solution concentrations used were 0.5%; 1%; 3%; and 5% for each column, respectively. This study resulted in a ZBM which has a 99 Mo adsorption capacity of 167.5 ± 3.4 mgMo/g ZBM, as well as in a yield eluate of 99m Tc of up to 70%, and the find that the optimum NaOCl concentration was 3%. The use of sodium hypochlorite solution affected 99 Mo breakthrough. The higher sodium hypochlorite concentration used, the more 99 Mo breaktrough exist on 99m Tc eluate. Received: 22 October 2014; Revised: 21 April 2015; Accepted: 21 May 2015

Mechanism of 99Mo adsorption and 99mTc elution from zirconium-based material in 99Mo/ 99mTc generator column using neutron-irradiated natural molybdenum

The 99Mo adsorption and 99mTc elution mechanism were investigated using SEM–EDS to analyze the elemental composition of the adsorbent surfaces. From the changes of element composition, it was found that molybdate ions were adsorbed into the adsorbent by ion exchange with Cl− ion in the material. It was also revealed that 99mTc can be eluted in high oxidation state since the 99mTc in lower oxidation state easily made coordination bonds with other elements in the adsorbent.