• Nuclear Engineering and Technology
• /
• v.48 no.3
• /
• pp.613-623
• /
• 2016

Molybdenum-99 ($^{99}Mo$) is the most important isotope because its daughter isotope, technetium-99m ($^{99m}Tc$), has been the most widely used medical radioisotope for more than 50 years, accounting for > 80% of total nuclear diagnostics worldwide. In this review, radiochemical routes for the production of $^{99}Mo$, and the aspects for selecting a suitable process strategy are discussed from the historical viewpoint of $^{99}Mo$ technology developments. Most of the industrial-scale $^{99}Mo$ processes have been based on the fission of $^{235}U$. Recently, important issues have been raised for the conversion of fission $^{99}Mo$ targets from highly enriched uranium to low enriched uranium (LEU). The development of new LEU targets with higher density was requested to compensate for the loss of $^{99}Mo$ yield, caused by a significant reduction of $^{235}U$ enrichment, from the conversion. As the dramatic increment of intermediate level liquid waste is also expected from the conversion, an effective strategy to reduce the waste generation from the fission $^{99}Mo$ production is required. The mitigation of radioxenon emission from medical radioisotope production facilities is discussed in relation with the monitoring of nuclear explosions and comprehensive nuclear test ban. Lastly, the $^{99}Mo$ production process paired with the Korea Atomic Energy Research Institute's own LEU target is proposed as one of the most suitable processes for the LEU target.

• Advances in nano research
• /
• v.10 no.5
• /
• pp.461-470
• /
• 2021

Infection is one of the major mortality causes throughout the globe. Nuclear medicine plays an important role in diagnosis of deep infections such as osteomyelitis, arthritis infection, heart valve and heart prosthesis infections. Techniques such as labeled leukocytes are sensitive and selective for tracking the inflammations but they are not suitable for differentiating infection from inflammation. Anionic linear-globular dendrimer-G₂ was synthesized then conjugation to gemifloxacin antibiotic. The structures were identified by FT-IR, ¹H-NMR, C-NMR, LC-MS and DLS. The toxicity of gemifloxacin and dendrimer-gemifloxacin complex was compared by MTT test. Dendrimer-G₂-gemifloxacin was labeled by Technetium-99m and its in-vitro stability and radiochemical purity were investigated. In-vivo biodistribution and SPECT imaging were studied in a rabbit model. Identify and verify the structure of the each object was confirmed by FT-IR, ¹H-NMR, C-NMR and LC-MS, also, the size and charge of this compound were 128 nm and -3/68 mv respectively. MTT test showed less toxicity of the dendrimer-G₂-gemifloxacin than free gemifluxacin (P < 0.001). Radiochemical yield was > %98. Human serum stability was 84% up to 24 h. Biodistribution study at 50 min, 24 and 48 h showed that the complex is significantly absorbed by the intestine and accumulation in the lungs and affects them, finally excreted through the kidneys, biodistribution results are consistent with results from full image means of SPECT/CT technique.

• Journal of The Korean Radiological Technologist Association
• /
• v.25 no.1
• /
• pp.234-252
• /
• 1999

Purpose : Physical properties of radiophamaceuticals of technetium($^{99m}Tc$) and thallium($^{201}Tl$) have early been used for clinical diagnostics. The studies of those radiophamaceuticals have been contributed to the efficient to

• Journal of the Korean Society of Safety
• /
• v.12 no.3
• /
• pp.97-105
• /
• 1997

Mo-99(Molybdenum) is the only source of Tc-99m(Technetium) which is most frequently used in nuclear medical diagnostics and the demand is on the increase recently. Separation and refining of Mo-99 was investigated by adsorption and desorption on alumina. At pH=0.63, adsorption isotherm of Mo was fitted by Redlich ＆ Peterson equation using the adsorption experimental data. It was found that the pore diffusion model ($D_p=1.4{\times}10^{-6}cm^2/s, K_f/=0.4 cm/s$) agreed well with batch adsorption experimental data. RTDs(Residence Time Distributions ) were measured and axial dispersion coefficients were obtained in the fixed bed absorber according to the changes of the flow rate using 0.05% -NaCl. From the adsorption experimental data, it was shown that the behavior of breakthroughs depended on flow rate. Mo recovery yield was increased as adsorption flow rate was increased and desorption flow rate was decreased.

• Journal of Chest Surgery
• /
• v.28 no.4
• /
• pp.371-375
• /
• 1995

Surgical resection of lung cancer or other disease is recently required in patients with severely impaired lung function resulting from chronic obstructive pulmonary disease or disease extension. So prediction of pulmonary function after lung resection is very important in thoracic surgeon. We studied the accuracy of the prediction of postoperative pulmonary function using perfusion lung scan with 99m technetium macroaggregated albumin in 22 patients who received the pneumonectomy. The linear regression line derived from correlation between predicting[X and postoperative measured[Y values of FEV1 and FVC in patients are as follows: 1 Y[ml =0.713X + 381 in FEV1 [r=0.719 ,[P<0.01 2 Y[ml =0.645X + 556 in FVC [r=0.675 ,[P<0.01 In conclusion,the perfusion lung scan is noninvasive and very accurate for predicting postpneumonectomy pulmonary function.

• 대한핵의학회:학술대회논문집
• /
• 1999.05a
• /
• pp.189-192
• /
• 1999

$^{188}Re$ (${\beta}^-=2.2$ MeV; ${\gamma}^-$=155 keV; $T_{1/2}$=16.9 hours) is an attractive therapeutic radioisotope which is produced from decay of reactor-produced tungsten-188 parent ($T_{1/2}$=69 days). $^{188}W$ has been produced from the double neutron capture reaction of $^{186}W.\;^{188}Re$ can be easily obtained by elution of saline on alumina based $^{188}W/^{188}Re$ generator, which is commercially available. Complexes labelled with $^{188}Re$ have been developed for the radiotherapy treatment of diseases because of the desirable nuclear properties of the radioisotope and it's chemical properties similar to those of technetium, a well established diagnostic agent.

• Nuclear Engineering and Technology
• /
• v.31 no.4
• /
• pp.365-374
• /
• 1999

A nuclear design of fission moly production targets for a research reactor, HANARO was peformed. It was found that the use of MCNP-4A, ORIGEN-2 code was reliable for the analysis of production characteristics of $^{99}$ Mo in a target fuel at an irradiation holes. A parametric study was done for the optimization of target location, target dimension, target shape and fuel materials. It was shown that a fuel thickness was the most sensitive parameters and electro-deposited target gave the highest 99Mo yield ratio. A pellet target with vibro-compaction powder, however, showed the largest production capacity and better engineering feasibility even with less yield ratio. Ten kinds of optimized target design for both LEU and HEU satisfied all the given design constraints. The most favorable design was the HEU ring-shaped electro-deposited target, considered the safety limit, production yield, chemical process easiness, yield ratio, and amount of radioactive waste.

• Proceedings of the Korea Contents Association Conference
• /
• 2014.11a
• /
• pp.431-432
• /
• 2014

본 연구는 핵의학과에서 사용하는 $^{99m}Tc$에서 방출되는 광자에너지에 대하여 거리에 따른 인체에 대한 선량당량을 평가하였다. 그 결과 주사기 차폐기구 유무에 따라 선량당량이 차이를 보였으며, 심부선량은 차폐를 하지 않은 경우 평균 $216.026{\mu}Gy/h$, 1 mm 텅스텐 차폐를 하였을 경우 평균 $4.240{\mu}Gy/h$, 2 mm 텅스텐의 경우 평균 0.124 uGy/h의 선량을 보였다. 이에 따라 주사기 차폐기구를 필수적으로 사용하여야 하며 종사자 개개인의 피폭 관리에 항상 유념하여야 한다. 또한 본 연구결과를 바탕으로 종사자의 피폭 감소 방안에 대한 연구가 지속적으로 이루어 져야할 것으로 생각된다.

• Clinical and Experimental Pediatrics
• /
• v.46 no.9
• /
• pp.854-857
• /
• 2003

Purpose : It is known that single umbilical artery is frequently associated with gastrointestinal or urogenital anomaly, however, routine renal sonography has been debated in healthy neonate with isolated single umbilical artery. This study is designed to determine the usefulness of routine renal sonography in apparently healthy infants with an isolated single umbilical artery. Methods : Thirty healthy neonates with a single umbilical artery without a major anomaly from January 1995 to July 2002 were enrolled. The authors investigated the clinical background of babies and their mothers after renal sonography after 72 hours of age. When the abnormalities were found at the first renal sonography, the severity of hydronephrosis and degree of obstruction and renal function were analyzed by follow up renal sonography, voiding cystourethrography(VCUG) and technetium-99m-dimercaptosuccinic acid(DMSA) scan or technetium-99m-mercaptoacetyl-triglycerine (MAG3) scan. Results : Among the 30 healthy patients with isolated single umbilical artery, five patients(16.7%) showed abnormalities on first renal sonography with one major(3.3%) and four(13.4%) minor renal anomaly(minimal or mild hydroneohrosis). One major renal anomaly(severe hydronephrosis) showed severe decreased renal function on MAG3 scan without reflux, and the other four minor regressed spontaneously on follow up study. Conclusion : The value of routine early renal sonograpy for detecting renal anomaly in healthy infants with an isolated single umbilical artery remained unclear because most of the anomalies would regress spontaneously in the follow up study.

• Childhood Kidney Diseases
• /
• v.11 no.2
• /
• pp.220-228
• /
• 2007

Purpose : We studied the value of clinical signs, laboratory findings and $^{99m}technetium$ dime-rcaptosuccinic acid(DMSA) scan in predicting the presence of vesicoureteral reflux(VUR) in children with first febrile urinary tract infection(UTI). Methods : A retrospective analysis of 84 hospitalized children with first febrile UTI was performed. They underwent DMSA scan and voiding cystourethrography(VCUG) during the acute phase, and were divided into three groups according to the results of the VCUG: absence of VUR, mild(grade I-II) and severe VUR(grade III-V). We studied the relation of VUR to age, gender, fever duration, causative organism, white blood cell count, serum C-reactive protein and result of DMSA scan. Results : Among 84 patients, 6 had mild and 17 had severe VUR. Thirty-eight had abnormal DMSA scan. results Patients with VUR were older than those without VUR(P<0.01). There was a lower probability of infection with Escherichia coli in patients with severe VUR than in those with mild and absent VUR(P<0.01). An abnormal DMSA scan correlated with the presence and severity of VUR(P<0.05). Severe VUR was present in 10.9% of patients with normal DMSA scan. The sensitivity, specificity, positive and negative predictive values of the DMSA scan in predicting the presence of VUR were 69.6%, 63.9%, 42.1%, and 84.8%, respectively. Conclusion : An abnormal DMSA scan correlated to the presence and severity of VUR, but the sensitivity, specificity and positive predictive value of the DMSA scan were low. There-fore, patient with an abnormal DMSA scan requires a VCUG. In order to prevent missing the 10.9% of patients with severe VUR but normal DMSA scans, a VCUG should be performed in patient with normal DMSA scan.