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A method for determining activity of 89Sr and 90Sr in a sample where 90Sr and 90Y are not in equilibrium is presented. The method consists of an experimental design and equations for accurately calculating activity of 89Sr and 90Sr based on 90Y ß particle counts and the total counts of ß particles emitted from 89Sr, 90Sr, and 90Y in a sample. The equations are derived based on chemical separation sequences, ß particle counting sequences, and the Bateman equation. The presented method allows simultaneously obtaining the activity of 89Sr and 90Sr in a non-equilibrated 90Sr/90Y system without the need of Cerenkov counting.

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89SrCl2 radiopharmaceuticals is mainly used for bone pain palliation in the cancer patients, is being produced in FBTR via 89Y(n, p)89Sr using yttria target. The irradiated yttria target is chemically processed in high pure quartz distilled nitric acid medium in hot cell facility, to avoid the corrosion of components of hotcell due to chloride ions while using HCl medium. Being ionic species, the purified 89Sr(II) cation in aqueous solution containing bulk nitrate and other trace anions, exists as SrXn species where X: F-, Cl-, Br-, NO3-, PO43- and SO42-, n: stoichiometric anion content. The aim of the manuscript is to standardise an efficient ultra-low level anion purification method (ppb range) for the conversion of SrXn to SrCl2 and estimate the residual anionic impurities as recommended by the appropriate source specifications for its medical application. Various methods were standardised for the removal of anions in the SrCl2 source produced by the above process which include evaporation, calcination, anion exchange column, cation exchange column as well as its combination with pre-concentration column of ion chromatography (IC) technique using 89Sr tracers as well as FBTR produced 89Sr solution. Assay of 89Sr and other anions including nitrate for the above study were accomplished using Cerenkov counting and ion chromatography respectively. Thus evaporation-calcination-column chromatography mode was finalised to obtain pure SrCl2 source free from nitrate and other anionic impurities. This is the first ever systematic study for the Radiochemical quality control of nca 89SrCl2 radiopharmaceutical produced in a fast reactor. This study also finds its application to any analytical lab as well as industry where there is a requirement of anion purification in the ppb level.

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We present the radioanalytical strategies used for the determination of strontium radioisotopes in routine and emergency samples. While in routine monitoring, the main goal is to achieve limits of detection as low as possible. In emergency, priority is given to the rapid procurement of data about a contamination. The parameters accuracy, precision and detection limit of the radiochemical methods are shown. We present the results obtained over the past 22 years in proficiency tests and in the analysis of reference materials.

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The production capacity of 89Sr and 90Sr in the 2 MW MSR are evaluated. The gaseous 89Kr and 90Kr are extracted from the core through the helium bubbling system, and then decay to 89Sr and 90Sr, respectively. In order to improve purity of 89Sr product, two cooling devices are adopted in the 89Sr and 90Sr production system. The annual yields of 89Sr and 90Sr are about 9000 Ci and 32 Ci, respectively, and the impurity of 89Sr product is less than 2 ppm which can meet the medical requirement.

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Bone metastasis develops in multiple malignancies with a wide range of incidence. The presence of multiple bone metastases, leading to a multitude of complications and poorer prognosis. The corresponding refractory bone pain is still a challenging issue managed through multidisciplinary approaches to enhance the quality of life. Radiopharmaceuticals are mainly used in the latest courses of the disease. Bone-pain palliation with easy-to-administer radionuclides offers advantages, including simultaneous treatment of multiple metastatic foci, the repeatability and also the combination with other therapies. Several ߯- and α-emitters as well as pharmaceuticals, from the very first [89Sr]strontium-dichloride to recently introduced [223Ra]radium-dichloride, are investigated to identify an optimum agent. In addition, the combination of bone-seeking radiopharmaceuticals with chemotherapy or radiotherapy has been employed to enhance the outcome. Radiopharmaceuticals demonstrate an acceptable response rate in pain relief. Nevertheless, survival benefits have been documented in only a limited number of studies. In this review, we provide an overview of bone-seeking radiopharmaceuticals used for bone-pain palliation, their effectiveness and toxicity, as well as the results of the combination with other therapies. Bone-pain palliation with radiopharmaceuticals has been employed for eight decades. However, there are still new aspects yet to be established.

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The accident at the Chernobyl nuclear power plant (NPP) in Ukraine on April 26, 1986 led to a considerable release of radioactive material resulting in environmental contamination over vast areas of Belarus, Ukraine and western Russian Federation. The major health effect of the Chernobyl accident was an increase in thyroid cancer incidence in people exposed as children and adolescents, so much attention was paid to the thyroid doses resulting from intakes of 131I. Because cow's milk consumption was the main source of 131I intake by people, it was important to measure the 131I activity concentrations in cow's milk to calculate, or to validate, the thyroid doses to the exposed population. Almost 11,000 measurements of total beta-activity in cow's milk were performed using a DP-100 device during the first month after the Chernobyl accident in the most contaminated regions of Belarus. Using an ecological model and calibration coefficients for the DP-100 device the activity concentration of 131I in cow's milk was derived as well as the activity concentrations of the other radiologically important radionuclides, namely 134Cs, 137Cs, 89Sr and 90Sr. The activity concentrations of other radionuclides, such as 90Y, 132Te, 132I, 133I, 136Cs, 140Ba, 140La, 141Ce and 144Ce, in cow's milk were also estimated and were shown to be of minor importance. The concentrations of 95Zr, 95Nb, 103Ru and 106Ru in cow's milk were negligible. The data obtained in this study were validated by comparing derived 131I and 137Cs concentrations in cow's milk with gamma-spectrometry measurements performed in milk produced in the same location close to the same date. The results of this study were essential to assess and validate the radiation doses received by the subjects of epidemiological studies related to the health consequences of the Chernobyl accident.

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In case of a radiological emergency situation involving e.g. fission of uranium or plutonium, analysis of radioactive strontium will be of importance. The primary radionuclides of interest are 90Sr, its progeny 90Y and 89Sr. A few days following an event, 89Sr will be the predominant radioisotope of strontium. Most methods found in the literature are valid and applicable when measuring 90Sr, but when samples contain both 89Sr/90Sr interference problematics arise. How these interferences are dealt with will have an effect on the uncertainty of the 90Sr determination. This work aims at evaluating three measurement approaches, all mentioned in the literature, with respect to the measurement uncertainty when determining 90Sr in an emergency preparedness situation and to propose a suitable measurement strategy.

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As the first sodium cooled fast reactor in China, China Experimental Fast Reactor (CEFR) has many characteristics, such as high power rating, high neutron flux and high neutron leakage as its hard spectrum. These leakage neutrons can be used to produce 89Sr by fast neutrons (n, p) reaction. By means of some special designs, including designing optimized target assembly, choosing reasonable irradiation location and appropriate irradiation cycle length, in order to improve specific activity of 89Sr. The MNCP code was used to the calculations coupled ORIGRN2 procedure. The higher activity of 89Sr can be obtained by these optimization designs, so it is feasible to produce 89Sr in the fuel region of CEFR.

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Aim: The usefulness and safety of strontium chloride (89Sr), a radiopharmaceutical agent for painful bone metastasis, varies from patient to patient, but the reasons for why the usefulness and safety vary have not been elucidated. The purpose of this study is to explore the background factors of patients who experienced pain relief or bone-marrow suppression after 89Sr was administrated. Methods: In the cases of pain relief, we divided the results from a numeric rating scale (NRS) before and after 89Sr administration into effective and ineffective groups as outcomes. In the cases of bone-marrow suppression, we analyzed neutrophil cells, blood platelets, and hemoglobin levels, respectively, before and after 89Sr administration as outcomes. Then, we performed statistical analyses on both case groups. Results: The results showed that the background factors associated with pain relief were weight, the 89Sr dosage amount, NRS, eGFR, SCr, and Ca levels before 89Sr administration and the area of bone metastasis (number of sites reached). We found that background factors associated with bone-marrow suppression have a moderate significant correlation with hemoglobin, NRS, and SCr levels before 89Sr administration after investigating factors which influence neutropenia. In the case of thrombocytopenia, there was a moderate significant correlation with platelet counts before 89Sr administration. In the case of hypochromia, there was a moderate significant correlation with hemoglobin levels before 89Sr administration. Discussion: Our study could elucidate patient background factors associated with pain relief and bone-marrow suppression after 89Sr administration.

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Two different molecular radio-theragnostic principles are applied in prostate cancer, providing a personalised management for those patients. Firstly, radiopharmaceuticals with the same or similar mechanism of action but different energy (gamma-γ, eg 99mTc-diphosphonates or positron-ß+, eg 18F-NaF emitting isotopes) can be used to identify patients with osteoblastic metastases for a treatment with bone seeking beta (ß-) or alpha (α-) emitting radionuclides to deliver targeted molecular radiotherapy. A number of such ß- emitting molecules have been used for bone palliation. More recently, an alpha emitting 223Ra-dicholoride demonstrated not only symptomatic relief but also significantly improved overall survival in castration-resistant prostate cancer with predominant bone metastases. The second principle involves utilisation of the same prostatic specific membrane antigen (PSMA) or similar compound (eg PSMA-11, PSMA-617), but different label with either ß+ (68Ga) or γ (99mTc) emitting radioisotope for imaging and subsequently ß- (177Lu) or α (225Ac) emitting radionuclide for treatment.

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Rapid methods that are used during nuclear accidents or incident situations must first be implemented and validated in radioactivity measurement laboratories, so they can be ready to provide quick answers to governments, regulatory organizations and people in such situations. As these accident situations are rare and the methods are thus not frequently used, the best way to achieve this is to use the same methods for both routine environmental monitoring and rapid or emergency situations. Before this can be done, however, an analysis of the conditions under which a rapid method could be effectively used in routine situations should be carried out. This work analyses the performance of the rapid method for the simultaneous determination of 89Sr and 90Sr in milk, published by the IAEA, and compares it with another, more conventional method used for routine environmental purposes. Through numerical calculations and considering different 89Sr and 90Sr activities, we also conducted a study to obtain the optimum values for determination parameters - such as sample mass, counting times, time lapse between measurements and background counting times - that will allow the use of the IAEA rapid method as a routine environmental one.

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This work presents an optimized method for the determination of multiple samples containing 90Sr when its daughter 90Y is measured after chemical separation and in sequence, i.e. during its decay. Consequently the measurement times will increase for each subsequent sample, since there has been a longer time for decay before measurement. Compared to a previously published approach, when 90Y is measured during its ingrowth, the gain in total analysis time (time for ingrowth+ summation of measurement times) is not that large, particularly not for low background instruments. However, results for a large part of the samples can be delivered earlier.

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Objective To compare the effect of 89Sr radionuclide therapy and radiotherapy in the treatment of metastatic cancer pain of vertebral column. Methods 80 patients with cancer pain of vertebral metastasis in the second People's hospital of Yibin from April 2015 to April 2017, were randomly divided into the control group treated by radiotherapy treatment (n=40) and the the observation group treated by 89Sr radionuclide therapy(n=40), and the effect of treatment were compared between two groups. Results In the observation group, the total effective rate of pain response in patients with metastatic cancer pain of vertebral column was 85.0％, and the control group was 82.5％. There was no significant difference between two groups. The onset time of treatment in the observation group was (6.5±1.7)d, significantly shorter than that of the control group (12.9±2.6)d, and the difference was statistically significance (P<0.05). Conclusion The application of 89Sr radionuclide therapy in the treatment of vertebral metastatic pain is equivalent to the radiotherapy in improving the pain response, but the efficacy could be achieved in a short period of time, so it is worth popularizing widely in clinical practice.

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Objective To evaluate the efficacy and safety of combined therapy with 89Sr for treating skeletal-related events of prostate cancer. Methods Databases including PubMed,MEDLINE,EMBASE,the Cochrane library,CNKI,CBM and Wanfang were systematically searched since 89Sr was first reported in 1976 to September 2015 to include the randomized controlled trials (RCTs) of the combined therapy with 89Sr for skeletal-related events of prostate cancer.The statistical analysis was performed using Review Manager Version 5.2. Results A total of 18 RCTs involving 1 280 patients were analyzed.The results of meta-analysis indicated:there were statistically significant differences in the pain relief rate [OR=4.71,95%CI(3.34, 6.62),P<0.000 1],decrement rate of bone metastasis[OR=3.63,95%CI(2.60,5.09),P<0.000 1] and improvement rate of life quality [OR=2.16,95%CI(1.16,4.02),P<0.05].Progression-free survival of patients in experimental group was significantly longer than that in control group [HR=0.84,95%CI(0.73,0.97),P=0.02].No significant difference was found in overall survival [HR=0.82,95%CI(0.65,1.02),P=0.07].There were no significant differences in the incidence of adverse events [OR=1.46,95%CI(0.98,2.17),P>0.05]. Conclusion Combined therapy with 89Sr has better efficacy and comparable safety profile compared with standard therapy.However,the quality and sample size of the included studies are limited,so more high-quality and large-sample RCTs are needed to verify the validity.

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The internal bremsstrahlung (IB) spectrum of (89)Sr, which is a unique first forbidden beta emitter, is studied in the 1-100keV photon energy regime. The IB spectrum is experimentally measured using a Si(Li) detector, which is efficient in this photon energy regime, and is compared with the IB distributions that are predicted by the Knipp, Uhlenbeck and Bloch (KUB), Nilsson, and Lewis and Ford theories. In the soft energy regime up to 15keV, the measured results are in agreement with all the aforementioned theories. However, from 16-30keV, the experimental results are in agreement with the Lewis and Ford theory, which applies to forbidden transitions, and at higher photon energies, the Nilsson theory best describes the measured results. The differences among the different theories also increase with the photon energy. The effect of the electrostatic Coulomb field on the IB process for beta emitters with different end-point energies is investigated by comparing the ratio of the IB probabilities predicted using the KUB and Nilsson theories for (35)S and (89)Sr, i.e., soft and hard beta emitters, respectively. The Coulomb effect is shown to be significant in the high photon energy regime and for beta emitters with low end-point energies.

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Objective: To evaluate and compare the safety and efficiency of the combined therapy of 89Sr plus zoledronic acid and those of 89Sr-chloride alone, in patients with painful bone metastases. Methods: A total of 87 patients with osseous metastasis were ran-domly divided into treatment groups of 89Sr-chloride alone (group A, 53 patients) and 89Sr plus zoledronic acid (group B, 34 patients). A total of 17 patients in group B received zoledronic acid 2-14 days after 89Sr therapy, and 13 other patients in the group received 89Sr 4-7 days after zoledronic-acid therapy. Pain response and KPS score were evaluated after the different treatments. Results: No obvious bone marrow suppression and liver damage were found in all cases. All patients who received both 89Sr-chloride and 89Sr plus zoledronic acid showed reduced bone pain and total discomfort, as well as improved KPS score, but the response was more pronounced in group B (P=0.047; P=0.036). No statistical differences in pain score and KPS scores were observed between the groups treated with zoledronic acid first and 89Sr therapy first (P=1.000; P=0.667). Comparison of bone pain relief and changes in the KPS score of different primary tumors after treatment with 89Sr-chloride or 89Sr plus zoledronic acid showed no statistical significance. Conclusion: Compared with 89Sr-chloride, treatment with 89Sr plus zoledronic acid was more effective in patients with painful bone metastases. The safety of these two treatments are similar.

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Measurements for determining the activity of (89)Sr and (90)Sr in reactor coolant water are associated with limitations due to interferences from radionuclides with similar chemical properties and ß(-)-energies. From a measurement bias point-of-view these interferences would result mainly in an overestimated activity concentration of (90)Sr. In order to address the interference problem, a common and well-known method was used in order to show the need for sufficient decontamination. An improvement was achieved by taking the sample through two initial strontium separations in order to increase the decontamination factor. This method determines the activity concentration of (89)Sr and (90)Sr, via its daughter nuclide (90)Y, by Cherenkov counting. This work is primarily based on theoretical calculations of strontium-, yttrium- and other potential interfering radionuclide ratios after instant fission. The work done to confirm the theoretical calculations were carried through on spiked strontium standard solutions and fresh reactor coolant water. The reactor coolant water was known to contain interferences at a composition resembling that of instant fission. The detection limit for double separation was calculated to 0.17 Bq/kg for (90)Sr and 0.38 Bq/kg for (89)Sr. When using methods that solely rely on strontium resins, this paper shows that the decontamination factor (DF) is significantly higher when using double separation than that of a single separation. The paper also shows that the DF of an initial double strontium separation is as effective when it comes to removing high ratio interferences as separations done with both Sr- and Ln-resin (EiChrom Technologies, Inc., 2003; Tovedal et al., 2009b). However, 'old' samples, where e.g. (140)Ba and (89)Sr has decayed, does not benefit from double separation. Furthermore, samples with low ratios of interfering radionuclides does not benefit from using this method either, seeing as this is a more time consuming method due to the double separations.

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The only commercial TDCR counter from Hidex Oy (Finland), comprising three photomultiplier tubes, was tested at the two National Metrology Institutes (NMIs) PTB and ENEA. To this end, the two NMIs purchased a Hidex 300 SL TDCR counter (METRO version) each and carried out various tests at their laboratories. In addition, the two institutions agreed to organize a bilateral comparison in order to acquire information on the reproducibility of the results obtained with the counters. To achieve this, PTB prepared some (89)Sr liquid scintillation samples, which were first measured in various counters at PTB and then shipped to ENEA for comparative measurements. The aim of this paper is to summarize the findings on the counter characteristics and adjustments. In addition, the results of the bilateral comparison between PTB and ENEA are presented and the results from various commercial counters using the CIEMAT/NIST efficiency tracing and the TDCR method are discussed.

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Objective To evaluate the efficacy and the toxicity of 89Strontium( 89 Sr) radionuclide therapy for the senile patients with bone metastatic cancer, and study the effects of 89 Sr on the image of bone metastasis, and to assess the utility of 89 Sr treatment for the senile patients in rehabilitation. Methods The effect on pain relief and the side effects of 27 senile patients with bone metastatic cancer were observed. The bone SPECT image was compared between those before and after the treatment, blood routine and blood biochemistry was tested. Results The total response rate was 70.4%, while the response rate of bone metastasis originated from prostatic cancer and breast cancer was 78.9%. A few metastasis sites in bone image disappeared or the concentration in the image became weak. A mild reversible harm to bone marrow function was the main side effect. 89 Sr had a little effect on blood biochemistry. Conclusion Radionuclide therapy with 89 Sr was an effective and well-tolerated method for the senile patients with bone metastatic cancer, which was a novel approach for pain-relief and rehabilitation of senile patients with bone metastatic cancer.

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Objective To evaluate the therapeutic effect and side effects of 89Sr metastron on treating multiple osseous metastasis tumor. Methods The total 83 patients had been treated by intravenously injecting 89Sr metastron at a dose of 2.22 MBq/kg. Results Among 83 cases, 31.3% of them got complete remission, 37.3% moderate remission, and 18.1% slight remission. The total effective rate was 86.7%. The side effects were mild, and only white blood cells and platelets transiently fell by 20%. Conclusion Internal radiotherapy with 89Sr metastron is the good alternative in treating multiple osseous metastasis tumor.