Synthesis and Characterization of Ordered and Disordered Mesoporous Alumina as High-Performance Molybdenum-99 Adsorbents

Molybdenum-99 (99Mo) is the parent radioisotope of technetium-99m (99mTc),an essential medical radioisotope for diagnostic agents in nuclear medicine.In 99Mo/99mTc generator, a chromatography column system with 99Mo adsorbent as afiller is usually used to produce 99mTc in hospitals. However, it is still challenging to find high-performance adsorbentsfor Mo adsorption.We have synthesized both ordered and disordered mesoporous alumina and compared their performance as 99Mo adsorbents. These materials were prepared via a soft-templated method using a triblock copolymer as the template, followed by air calcination at 400°C.The amount of nitric acid (HNO3) and the drying time were adjusted systematically to synthesize the ordered mesoporous alumina. The obtained ordered and disordered mesoporous alumina were characterized by low-and wide-angle X-ray diffractions (XRD), nitrogen adsorption-desorption, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The 99Mo adsorption capacities of these materials were evaluated by using the batch method. The experimental results show that the ordered mesoporous alumina hasa higher 99Mo adsorption capacity of 72.06 mg(Mo)g-1 than the disordered mesoporous alumina (50.12 mg(Mo)g-1). The results indicate the excellent potential of ordered mesoporous alumina as an adsorbent for the 99Mo/99mTc generator column

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

Molybdenum produced from fission of U-235 is the most desirable precursor for 99Mo/99mTc generator system as it is non-carrier added and has high specific activity. However, in the last decade there has been short supply of 99Mo due to several constrains. Therefore, there have been many works performed for development of 99Mo/99mTc generator system using 99Mo which is not produced from either LEU or HEU. This report deals with development of 99Mo/99mTc generator system where zirconium-based material (ZBM) is used as adsorbent of neutron-activated 99Mo. The system was prepared by firstly irradiating natural Mo in the G. A. Siwabessy reactor to produce neutron-activated 99Mo. 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 99Mo 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 99Mo breakthrough. The columns were then eluted daily with saline solution for up to one week. The yield of 99mTc was found to be between 53.7 – 74% (n= 5). All 99mTc eluates were clear solutions with pH of 5. Breakthrough of 99Mo in 99mTc eluates was found to be 0.031 ± 0.019 μCi 99Mo/ mCi 99mTc (n= 5) which was less than the maximum activity of 99Mo allowed in 99mTc solution (< 1 µCi 99Mo/mCi 99mTc). Aluminum breakthrough in 99mTc eluates was found to be less than 10 ppm. The radiochemical purity of 99mTc in form of Na99mTcO4 was > 99%. Radiolabeling of this 99mTc towards methylene diphosphonate (MDP) kit gave a radiolabelling efficiency of 99%. In summary, a new 99Mo/99mTc generator system that used neutron-activated 99Mo and ZBM as its adsorbent has been successfully prepared. The 99mTc produced from this new 99Mo/99mTc generator system attained the quality of 99mTc required for medical purposes.Received: 23 Februari 2016; Revised: 13 July 2016; Accepted: 17 July 201

Preparation and Characterization of Zirconia Nanomaterial as a Molybdenum-99 Adsorbent

The present study deals with the synthesis and characterization of ZrO2 nanomaterial which can be used as an adsorbent for Molybdenum-99 (99Mo). The adsorbent can potentially be utilized as the material for 99Mo/99mTc generator column. Using the sol-gel method, monoclinic nanocrystalline zirconia was synthesized from zirconium oxychloride in isopropyl alcohol reacted with ammonium hydroxide solution in isopropyl alcohol resulting in a white gel. The gel was subsequently refluxed for 12 hours at ~95°C and pH at ~4 and then dried at 100°C. The drying gel was then calcined at 600°C for two hours. Meanwhile the orthorhombic nanocrystalline zirconia was obtained by reacting zirconium oxychloride solution with 2.5 M ammonium hydroxide solution which resulted in a white gel. The gel was then refluxed for 24 hours at ~95°C and pH at ~11 and then dried at 100°C. The drying gel was then calcined at 600°C for two hours. These materials were characterized using FT-IR spectroscopy, X-ray diffraction (XRD), and Transmission Electron Microscope (TEM). The Scherrer method is used for determination of crystallite size. The FT-IR spectra for both materials show absorption peak at 450-500 cm-1 which are attributed to Zr-O bond. The XRD pattern of monoclinic nanocrystalline form shows crystalline peaks at 2θ regions of 28.37°, 31.65°, 34°, 36°, and 50.3° with average crystallite size of 2.68 nm. Meanwhile, the XRD pattern of orthorhombic nanocrystalline form shows crystalline peaks at 2θ regions of 30°, 35°, 50°, and 60° with average crystallite size of 0.98 nm. The TEM micrograph indicates that the zirconia nanomaterials prepared were quite uniform in size and shape.Received: 12 November 2015; Revised: 9 September 2016; Accepted: 20 September 201

Synthesis of Nano-α-Al2O3 for 99Mo Adsorbent

The fission-product 99Mo, having a high specific activity, is commonly used in alumina-based 99Mo/99mTc generator. Due to the limitation on the use of fission-product 99Mo, an alternative route for 99Mo production, namely activation of natural molybdenum using thermal neutron, has been explored. Unfortunately, this neutron-activated 99Mo has a low specific activity. Therefore, 99Mo/99mTc generator based on neutron-activated 99Mo requires a column with higher capacity absorbent. Thus, in this study, the nanomaterial of alumina (nano-a-Al2O3) was synthesized which was expected to have a higher 99Mo adsorption capacity, so that nano-a-Al2O3 could be potentially used as a matrix of column for 99Mo/99mTc generator based on neutron-activated 99Mo. Nano-a-Al2O3 was synthesized by using sol-gel method and characterized using FTIR spectroscopy, X-ray diffraction (XRD), and transmission electron microscopy (TEM). In addition, the Scherrer method was used to determine the size of the crystals. To determine the 99Mo adsorption capacity of the synthesized nanoalumina, the nano-a-alumina was soaked in nitric acid solution for one hour at room temperature followed by removing the filtrate. Then, the nano-a-alumina was soaked in 99Mo solution (Na299MoO4) at certain conditions. The FTIR spectra for nano-a-alumina showed adsorption peak at 450-500 cm-1 which indicated the presence of Al-O bond. The XRD patterns of nanoalumina crystals showed peaks at 2θ region of 25.8°, 35.9°, 38°, 52.8°, and 57.7°, indicating that the synthesized alumina had an α-phase with an average crystal size of ~5.5 nm. The average 99Mo adsorption capacity of the synthesized alumina was 47.55 ± 12.3 mg Mo/g nano-a-Al2O3

Preparation and Characterization of Zirconia Nanomaterial as a Molybdenum-99 Adsorbent

The present study deals with the synthesis and characterization of ZrO2 nanomaterial which can be used as an adsorbent for Molybdenum-99 (99Mo). The adsorbent can potentially be utilized as the material for 99Mo/99mTc generator column. Using the sol-gel method, monoclinic nanocrystalline zirconia was synthesized from zirconium oxychloride in isopropyl alcohol reacted with ammonium hydroxide solution in isopropyl alcohol resulting in a white gel. The gel was subsequently refluxed for 12 hours at ~95°C and pH at ~4 and then dried at 100°C. The drying gel was then calcined at 600°C for two hours. Meanwhile the orthorhombic nanocrystalline zirconia was obtained by reacting zirconium oxychloride solution with 2.5 M ammonium hydroxide solution which resulted in a white gel. The gel was then refluxed for 24 hours at ~95°C and pH at ~11 and then dried at 100°C. The drying gel was then calcined at 600°C for two hours. These materials were characterized using FT-IR spectroscopy, X-ray diffraction (XRD), and Transmission Electron Microscope (TEM). The Scherrer method is used for determination of crystallite size. The FT-IR spectra for both materials show absorption peak at 450-500 cm-1 which are attributed to Zr-O bond. The XRD pattern of monoclinic nanocrystalline form shows crystalline peaks at 2θ regions of 28.37°, 31.65°, 34°, 36°, and 50.3° with average crystallite size of 2.68 nm. Meanwhile, the XRD pattern of orthorhombic nanocrystalline form shows crystalline peaks at 2θ regions of 30°, 35°, 50°, and 60° with average crystallite size of 0.98 nm. The TEM micrograph indicates that the zirconia nanomaterials prepared were quite uniform in size and shape.Received: 12 November 2015; Revised: 9 September 2016; Accepted: 20 September 201

Molybdenum-99 (99Mo) Adsorption Profile of Zirconia-Based Materials for 99Mo/99mTc Generator Application

Technetium-99m (99mTc) plays a major role in diagnostic nuclear medicine and has not yet been replaced with any other radionuclides. It is available through the 99Mo/99mTc generator. The use of low-specific-activity 99Mo for 99Mo/99mTc generator application requires high adsorptive capacity sorbents. This study focused on the determination of 99Mo adsorption capacity of several zirconia materials, namely monoclinic nanozirconia, orthorhombic nanozirconia, sulfated zirconia,   and phosphated zirconia. These materials were synthesized by using the sol-gel method and characterized using FT-IR spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM-EDS). The determination of 99Mo adsorption capacity of these materials was carried out by soaking the materials in a Na299MoO4 solution with pH of 3 and 7, at temperatures ranging from room temperature to 90 °C, for 1 and 3 hours. The results indicated that monoclinic nanozirconia has a 99Mo adsorption capacity of 76.9 mg Mo/g, whereas orthorhombic nanozirconia, sulfated zirconia, and phosphated zirconia have 99Mo adsorption capacities of 150.1 mg Mo/g, 15.58 mg Mo/g, and 12.74 mg Mo/g, respectively. It appears that orthorhombic nanozirconia has the highest 99Mo adsorption capacity among the synthesized materials and can be applied as a candidate material for the 99Mo/99mTc generator

The Use of Sodium Hypochlorite Solution for (n,γ)99Mo/99mTc Generator Based on Zirconium-Based Material (ZBM)

The many problems in preparing fission product 99Mo led into this work to develop 99Mo/99mTc generator using neutron-irradiated natural MoO3 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 99mTc in performance of (n,γ)99Mo/99mTc generators based on the ZBM. The synthesized ZBM was coated with tetraethyl orthosilicate for improving the hardness of the material. The adsorption of [99Mo]molybdate into ZBM was carried out by reacting ZBM into [99Mo]molybdate solution at 90°C to form ZBM-[99Mo] molybdate. ZBM-[99Mo]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 99Mo adsorption capacity of 167.5 ± 3.4 mgMo/g ZBM, as well as in a yield eluate of 99mTc of up to 70%, and the find that the optimum NaOCl concentration was 3%. The use of sodium hypochlorite solution affected 99Mo breakthrough. The higher sodium hypochlorite concentration used, the more 99Mo breaktrough exist on 99mTc eluate.Received: 22 October 2014; Revised: 21 April 2015; Accepted: 21 May 201

Sintesis Poli N-Isopropilakrilamida (PNIPA)/Polityrosin (PTYR) Interpenetrating Polymer Networks (IPNs) Bertanda Iodium-125

Saat ini perkembangan polimer telah semakin maju, berbagai aplikasi polimer telah dikembangkan baik di sektor energi, pangan maupun kesehatan. PNIPA/PTYR IPNs bertanda iodium-125 dapat dimanfaatkan sebagai sumber terapi kanker. PNIPA/PTYR merupakan polimer peka temperatur. Tujuan dari penelitian ini adalah sintesis PNIPA/PTYR IPNs bertanda iodium-125. Polityrosin ditandai dengan iodium-125 kemudian secara simultan direaksikan dengan monomer N-isopropilakrilamida melalui polimerisasi radikal bebas dengan inisiator amonium persulfat (APS) dan tetrametiletilenediamin (TEMED) untuk memperoleh PNIPA/PTYR IPNs bertanda iodium-125. Kemurnian radiokimia PNIPA/PTYR IPNs bertanda iodium-125 diukur dengan krom atografi lapis tipis (KLT) dengan fasa gerak 2 propanol: 1 butanol: 0,2 M NH4OH. Selain Itu, stabilitas PNIPA/PTYR IPNs bertanda iodium-125 diuji pada media air. PNIPA/PTYR IPNs telah berhasil ditandai dengan iodium-125 dengan rendemen penandaan sebesar 37,6 ± 4,2 % (n = 3). Hasil pengamatan visual, ditunjukkan bahwa polimer mengalami Perubahan sifat pada temperatur 32 oC sampai dengan 34°C. Hasil H-NMR hanya menunjukkan spektrum dari polimer PNIPA. Berdasarkan pemeriksaan KLT, kemurnian radiokimia PNIPA/PTYR IPNs bertanda iodium-125 adalah 95,93%. Pengujian stabilitas polimer bertanda iodum-125 pada media air pada T = 37°C selama 2 minggu menunjukkan bahwa iodium-125 yang masih tertahan pada polimer adalah 71,3 ± 6,2 %