Subjects: Chemistry >> Nuclear Chemistry submitted time 2024-05-02
Abstract： Abstract Background：Human epidermal growth factor receptor 2 (HER2) is widely present in many malignant tumors.It is associated with poor prognosis. Particularly in breast cancer, however, there is heterogeneity in HER2 expression.Currently immunohistochemistry and fluorescence
are used for assessing HER2 status. However they have so much significant limitations.HER2 receptor imaging has significant advantages. It is a potential option for detecting HER2-positive lesions of Radiolabeled mimetic peptides.Purpose：To prepare a 18F labeled human epidermal growth factor receptor2(HER2) peptide B2-S22-AFA(18F-NFP-TP1296),and evaluate its biodistribution and microPET characteristics.Methods:The tracer conjugate was labeled with 18F in one step.18F-NFP-TP1296 was performed in vitro studies and MicroPET imaging in the SKBR-3 breast cancer model.Rusults:18F-NFP-TP1296 was synthesized in about 30 min with the non-decay corrected yields more than 10%, and radiochemical purity more than 95%.MicroPET imaging revealed that the SKBR-3 xenografts were visualized and the tumor uptakes were 5.63±0.14%ID/g、6.26±0.27%ID/g and 5.83±0.44%ID/g at 30min、60min and 120min.The corresponding tumor-to-blood and tumor-to-muscle ratios were 3.21±0.32、4.08±0.73 and 1.69±0.18 respectively, and 1.55±0.11%ID/g、1.84±0.12%ID/g and 3.10±0.30%ID/g at 30、60 and 120min. The lung metastasis tumor uptakes were 2.2%ID/g、2.5%ID/g and 2.1%ID/g at 30、60 and 120min.Conclusion：18F-NFP-TP1296 can be successfully labeled by one-step method.The 18F-NFP-TP1296 probe owns the advantages of favorable imaging properties, convenient preparation, excellent stability, safety, rapid clearance in the blood, which support its application for further research.
Subjects: Chemistry >> Nuclear Chemistry submitted time 2024-04-09
Abstract： In the process of accelerated development of nuclear medicine department in recent years, the construction of decay tanks and the storage time of radioactive wastewater containing I-131 have become issues of great concern for environmental regulatory agencies and hospitals. Basic Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources (GB 18871), Radiation Protection and Safety Requirements for Nuclear Medicine (HJ 1188), and Reply to Consultation on Several Clauses of the Nuclear Medicine Standard have stipulated the compliant discharge methods for radioactive wastewater containing I-131 from hospitals. This paper presents a theoretical calculation formula for the total activity of iodine-131 when a delay tank in a hospital is full. It demonstrates that among the three compliant disperse methods for radioactive wastewater containing iodine-131 in the decay tank, the method specified in GB 18871 is advantageous for the operation of the nuclear medicine department in the hospital. The paper also introduces the RJ equation group, which addresses the calculation of minimum decay time and volume of the decay tank. The actual measured data from four hospitals demonstrates that when the temporary storage period for radioactive wastewater containing iodine-131 reaches the minimum time calculated by the RJ equations, the total discharge activity of iodine-131 complies with the national environmental protection standards.These findings provide clear and specific guidance for the construction of decay tanks in nuclear medicine departments and for the supervision and inspection conducted by regulatory authorities.
Subjects: Chemistry >> Nuclear Chemistry submitted time 2023-06-13
Abstract： Objective: We herein fabricated a branched structure containing AO groups on polypropylene/polyethylene spun-laced nonwoven (PP/PE SNW) fibers using grafting polymerization induced by radiation (RIGP) to improve AO utilization. Methods: The chemical structures, thermal properties, and surface morphologies of the raw and treated PP/PE SNW fibers were studied. The adsorption properties were investigated using batch adsorption experiments in simulated seawater with an initial uranium concentration of 500 μg·L-1 (pH 4, 25℃). Results: The maximum adsorption capacity of the adsorbent material was 137.3 mg·g-1 within 24 h; moreover, the uranyl removal reached 96% within 240 min. Limitations: Only simulated seawater adsorption experiments have been conducted, and real seawater adsorption experiments are yet to be conducted. Conclusions: The adsorbent had an AO utilization rate of 1/3.5 and was stable over a pH range of 4–10, with good selectivity and reusability, demonstrating its potential for seawater uranium extraction.
Subjects: Chemistry >> Nuclear Chemistry submitted time 2023-06-06
Zhang, Hang
Ao, Yin-Yong
Wang, Yue
Zhao, Shang-Jie
Sun, Jia-Yang
Zhai, Mao-Lin
Li, Jiu-Qiang
Peng, Jing
Li, Hui-Bo
Abstract： N,N,N’,N’-Tetraoctyl diglycolamide (TODGA) is one of the most promising extractants tailored for high-level liquid radioactive waste treatment during nuclear fuel reprocessing. The γ-radiolysis of TODGA (0.2 mol/L) in n-dodecane (nDD) solution with and without pre-equilibrated 3.0 mol/L HNO3 was investigated using HPLC and UPLC-QTOF-MS and compared with the γ-radiolysis of neat TODGA in this study. With increased absorbed doses, the concentration of TODGA decreased exponentially for the studied systems. Moreover, pre-equilibration with HNO3 (3.0 mol/L) slightly influenced the γ-radiolysis of TODGA in nDD. Seven radiolytic products generated from the rupture of the C – C, C – O, and C – N bonds in TODGA were identified in the studied extraction system. The influence of γ-radiation on TODGA/nDD for the extraction of Eu(III) was evaluated using the first combination of extraction experiments and density functional theory (DFT) calculations, in which the complexations of Eu(III) with TODGA and its radiolytic products were systematically compared. Based on the radiolysis kinetic model of TODGA, the slope curve of the distribution ratio of Eu(III) (DEu ) and the absorbed dose, and fluorescence titration analysis, the empirical equation of the absorbed dose and DEu was obtained successfully. Below 300 kGy, the experimental DEu agreed well with the obtained empirical equation for TODGA/nDD. Conversely, at a high absorbed dose, the experimental DEu was higher than the theoretical DEu based on the empirical equation because the radiolytic products of TODGA with similar coordination structures still possessed partial complexation toward Eu(III), which was confirmed by DFT calculations. This work provides a method to predict the extraction distribution ratio of an irradiated extractant system and to understand the complex extraction process.
Subjects: Chemistry >> Nuclear Chemistry submitted time 2023-05-31
Abstract： The rapid development of advanced techniques for selective and efficient U(VI) extraction from aqueous solutions is essential for addressing U(VI) environmental pollution and energy issues. Here, we share recent progress in U(VI) extraction from aqueous solutions, especially the most frequently applied techniques such as adsorption, catalysis (photocatalysis, piezocatalysis, and electrocatalysis), chemical deposition, and reduction by zero-valent metal particles. We attempt toelucidate the strategies and various mechanisms that contribute to the enhancement of selective U(VI) extraction. At the end of our review, we highlight the outlook, challenges, and prospects for the development of this field.
Hits
Hits
Downloads
Comment
YES