• 핵의학기술
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• 제18권2호
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• pp.68-72
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• 2014

핵의학 검사는 반감기로 인한 동위원소의 잔류로 당일에 두 가지 검사를 시행하는데 어려움이 있다. 본 연구는 $^{18}F$-FDG와 $^{99m}TcO_4{^-}$의 상호 영향을 연구함으로써 당일 검사를 진행할 경우 고려될 사항에 대해 알아보고자 한다. NEMA-1994 Phantom을 이용하여 세 번의 실험을 진행했다. 첫 실험은 $^{99m}TcO_4{^-}$을 HOT과 BKG 비 4:1로 만들어 GE사의 INFINIA 장비로 SPECT를 시행하였고, BKG 영역에 $^{18}F$-FDG 37 MBq을 주입 후 동일 조건으로 60분에 1회씩 13회 Scan 했다. 두 번째는 $^{18}F$-FDG를 HOT과 BKG 비 4:1 로 만들어 GE사의 PET/CT Discovery 600 에서 Scan 하였고, BKG 영역에 $^{99m}TcO_4{^-}$을 148 MBq 주입 후 동일 조건으로 60분에 1회씩 6회 Scan 했다. 마지막 실험은 $^{18}F$-FDG를 HOT과 BKG 비 4 : 1로 만들고 1 Bed Scan 후 $^{99m}TcO_4{^-}$을 148 MBq 및 296 MBq씩 증가 시키며 같은 조건으로 1 Bed Scan했다. HOT과 BKG 영역의 비, CNR 혹은 SNR 그리고 총 획득 계수를 측정 후 비교 했다. $^{18}F$-FDG는 SPECT 시행 시 비율 및 CNR에 유의한 차이를 보였다(p>0.05). $^{99m}TcO_4{^-}$는 PET/CT 시행 시 비율 및 SNR이 유의한 차이를 보이지 않았다(p<0.05). $^{99m}TcO_4{^-}$이 PET/CT 검사의 Total Counts를 감소시킨다는 결과를 획득했다. PET/CT 검사를 한 경우 12시간 까지도 $^{99m}TcO_4{^-}$을 이용한 검사에 영향을 미칠 수 있으며, $^{99m}TcO_4{^-}$를 먼저 시행한 경우에는 PET/CT 검사에 SUV 및 SNR에 영향은 없지만 검출 효율을 감소시켰다. 당일 검사 시에는 $^{99m}TcO_4{^-}$을 이용한 검사를 먼저 진행하고 PET/CT의 검사 시간을 늘려 검출 효율을 보완하는 방법을 권장하고자 한다.

• 대한방사성의약품학회지
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• 제6권1호
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• pp.3-9
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• 2020

Tetraiodothyroacetic acid (tetrac) is a derivative of thyroid hormone T₄ and causes anti-angiogenesis by blocking T₄ binding to integrin α_vβ₃. In this study, we synthesized [^99mTc]Tc-Cys-Asp-Gly(CDG)-tetrac and evaluated it in vitro as a tumor angiogenesis imaging ligand. The CDG was conjugated to tetrac as a chelator for technetium-99m labeling. The cold vial containing CDG-tetrac, sodium glucoheptonate, and reducing agent was completed under nitrogen-filled atmospheric glove bag. [^99mTc]Tc-CDG-tetrac was synthesized in quantitative yield by heating the cold vial with [^99mTc]TcO₄^- at 100℃ for 30 min. In vitro serum stability of [^99mTc]Tc-CDG-tetrac was measured by incubating the radioligand in 50% fetal bovine serum at 37℃ and analyzing the incubation mixture by radio-TLC, which showed high stability over 6 h (≥ 98%). Cell binding study was carried out by incubating [^99mTc]Tc-CDG-tetrac with human umbilical vein endothelial (HUVE) cells at 37℃ for 6 h. The cell binding of the radioligand increased from 100% at 0.5 h to 293.7% at 6 h in a time-dependent manner. For blocking study, the cells were incubated with the radioligand in the presence of either tetrac (20 μM) or cRGDyK (20 μM) at 37℃ for 4 h. The results demonstrated that the cell binding of the radioligand was inhibited by tetrac (19.1%) or cRGDyK (35.6%), indicating specific binding of the radioligand to integrin α_vβ₃. Thus, this study suggests that [^99mTc]Tc-CDG-tetrac may be a potential radioligand for tumor angiogenesis imaging.

• 한국콘텐츠학회논문지
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• 제20권10호
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• pp.395-400
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• 2020

2019년 10월부터 2020년 1월까지 대구P병원 핵의학과에서 SPECT 검사를 위한 입원환자 중 3-way 주사재료를 장착하고, ^99mTc 표지화합물을 투여하였던 주사기 120EA를 대상으로 하였다. 플라스틱 주사기 사용시 희석 횟수에 따른 평균 투여율은 ^99mTc-ECD가 90.87±11.08로 가장 높았으며, ^99mTc-DMSA가 75.28±7.43으로 가장 낮았다. 놈젝주사기 사용 시 희석횟수에 따른 평균 투여율은 ^99mTcO4가 93.58±7.96으로 가장 높았으며, ^99mTc-DMSA가 91.60±6.07로 가장 낮았다. ^99mTc-DMSA의 플라스틱 주사기와 놈젝주사기의 차이가 나는지 독립표본 t-검정 결과, 유의확률은 0.007로서 플라스틱 주사기와 놈젝 주사기의 평균은 다르므로 통계적으로 매우 유의하게 나타났다(p<0.01). 특히 신장검사에 사용하는 ^99mTc-DMSA는 소아 환자에게 주로 사용되는 방사성의약품으로 정확한 투여량이 중요하여 일반 플라스틱 주사기보다 놈젝 주사기의 사용이 필요하다고 판단된다.

• 치과방사선
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• 제20권1호
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• pp.53-62
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• 1990

This experiment was performed to clarify the effects of /sup 60/Co gamma irradiation on secretory function, amylase activity and contents of nucleic acids of parotid gland in rat. Experimental animals were divided into 6th hours, 3rd, 7th, 14th and 28th days after irradiation and control. The experimental animals are singly irradiated with 20Gy (2,000rad) through protective lead block. Secretory function of parotid gland was evaluted by uptake and clearance of /sup 99m/TcO₄. /sup 99m/TcO₄. 0.2μ ci/gm, was injected into peritonium in uptake groups. Rats were sacrified with cervical dislocation after 30 minutes and gland was excised. In the clearance group. pilocarpine nitrate (8㎎/㎏) was intraperitoneally injected at 30 minutes after /sup 99m/TcO₄ injection and rats were sacrified 30 minutes after pilocarpine injection. Radioactivity of excised parotid gland was measured by using of gamma counter and stimulation-secretion coefficients, uptake radioactivity divided by clearance radioactivity, was calculated. Amylase activity and contents of DNA and RNA were determined by spectrophotometry. The results obtained were as follows: 1. In the uptake test, the radioactivity of /sup 99m/TcO₄ per unit weight increase in experimental group except 6th hours group, compared with control groups and showed a peak at 3rd days after irradiation. 2. In the clearance test, the radioactivity of /sup 99m/cO₄per unit weight rose to a peak at 3rd days after irradiation and gradually recovered thereafter. 3. Stimulation-secretion coefficient of parotid gland decreased at 6th hours, 3rd and 7th days after irradiation, and gradually increased. 4. Amylase activity of parotid gland decreased in 3rd and 7th days group, and especially lowest in 3rd days after irradiation. 5. The contents of DNA showed no definite difference in all the experimental groups, but RNA was seemed to decrease with time after irradiation.

• Nuclear Engineering and Technology
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• 제4권4호
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• pp.327-330
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• 1972

낮은 방사능의 $^{99m}$ Mo으로부터 methyl ethyl ketone으로 추출하여 제조된 Na $^{99m}$ TcO$_4$를 가지고 폐검진에 사용되고 있는 $^{99m}$ Tc Ferric Hydroxide Macroaggregates를 제조하였으며 여러 pH 범위에서 입자의 크기와 수가 변하는 모양을 검토하였고 pH 6-7에서 평균입자의 크기가 scanning에 가장 적당한 20~60$\mu$이었다. 토끼와 인체에 주사하여 좋은 곁과를 얻었다.

• Toxicological Research
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• 제28권4호
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• pp.235-240
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• 2012

$^{99m}Tc$ tricarbonyl glycine monomers, trimers, and pentamers were synthesized and evaluated for their radiolabeling and in vivo distribution characteristics. We synthesized a $^{99m}Tc$-tricarbonyl precursor with a low oxidation state (I). $^{99m}Tc(CO)_3(H_2O)_3^+$ was then made to react with monomeric and oligomeric glycine for the development of bifunctional chelating sequences for biomolecules. Labeling yields of $^{99m}Tc$-tricarbonyl glycine monomers and oligomers were checked by high-performance liquid chromatography. The labeling yields of $^{99m}Tc$-tricarbonyl glycine and glycine oligomers were more than 95%. We evaluated the characteristics of $^{99m}Tc$-tricarbonyl glycine oligomers by carrying out a lipophilicity test and an imaging study. The octanol-water partition coefficient of $^{99m}Tc$ tricarbonyl glycine oligomers indicated hydrophilic properties. Single-photon emission computed tomography imaging of $^{99m}Tc$-tricarbonyl glycine oligomers showed rapid renal excretion through the kidneys with a low uptake in the liver, especially of $^{99m}Tc$ tricarbonyl triglycine. Furthermore, we verified that the addition of triglycine to prototype biomolecules (AGRGDS and RRPYIL) results in the improvement of radiolabeling yield. From these results, we conclude that triglycine has good characteristics for use as a bifunctional chelating sequence for a $^{99m}Tc$-tricarbonyl-based biomolecular imaging probe.

• 대한핵의학회지
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• 제27권2호
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• pp.270-276
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• 1993

$Technetium-^{99m}$ labeling method using bifunctional chelating agent cyclic DTPA has been evaluated with human polyclonal nonspecific IgG. IgG was conjugated with cyclic DTPA with various molar ratio. Reduction of $^{99m}Tc$ was done with $Na_2S_2O_4$ with various molar excess. Labeling efficiency and identification of polymer was confirmed with HPLC using TSK4000 SW column. Polymer was purified with 100 cm Sepharose 6LB column. Cultured $1{\times}10^9$ Staphylococcus aureus were injected into rat thigh 24 hours later labeled IgG was injected, and in vivo distribution was observed 4 and 24 hours thereafter. Reduction of $^{99m}Tc$ was optimal with the 10000-50000 times molar excess of $Na_2S_2O_4$. Polymer formation increased with increasing mloar excess of cyclic DTPA to IgG. Three step labeling-labeling DTPA conjugated IgG after reduction of $^{99m}Tc$-made more polymer than two two step labeling-simultaneous mixing DTPA conjugated IgG, $^{99m}Tc$ and $Na_2S_2O_4$. $^{99m}Tc$ blood clearance and lower uptake in the abscess and other organs. IgG conjugated with 200 times molar excess of cyclic DTPA showed slower blood clearance with 200 times molar excess of cyclic DTPA showed slower blood clearance than that of 200 times molar excess of cyclic DTPA showed slower blood clearance than that of 20 times molar excess. In the $^{99m}Tc$ labeling of IgG with cyclic DTPA for the immunoscintigraphy, obtimal labeling condition should be chosen, and effect of the $^{99m}Tc$ labeled IgG polymer should be considered.

• 대한수의학회지
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• 제44권1호
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• pp.15-21
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• 2004

This paper describes the development of $^{99m}Tc$ tricarbonyl cysteine as potential renal function diagnostic radiopharmaceutical and evaluation of its biological characteristics using experimental animals. l-Cysteine was labeled efficiently with $^{99m}Tc$ tricarbonyl precursor $([^{99m}Tc(CO)_3(H_2O)_3)]^{+})$ under 30 min heating at ${75^{\circ}C}$. Labeling yield and stability were analyzed by high performance liquid chromatography (HPLC). The biodistribution property of $^{99m}Tc$ tricarbonyl cysteine in mice and its dynamic imaging profiles in rabbits were carried out. To investigate the excretion mechanism of $^{99m}Tc$ tricarbonyl cysteine, tubular transport inhibition test with probenecid was adopted. $^{99m}Tc$ tricarbonyl cysteine was obtained with a high labeling yield under the moderate condition. The results of biodistribution experiments of $^{99m}Tc$ tricarbonyl cysteine in ICR mice at 3 and 90 min provided that $^{99m}Tc$ tricarbonyl cysteine was very highly accumulated in the kidney and bladder, thereby almost 99% of $^{99m}Tc$ tricarbonyl cysteine was excreted within 90 min post injection. The same results were confirmed by the whole body dynamic images for 30 minutes and static images in rabbits at given time intervals after injection. Renogram of $^{99m}Tc$ tricarbonyl cysteine in rabbits showed that its $T_{max}$ and $T_{1/2}$ of $^{99m}Tc$ tricarbonyl cysteine were $2.33{\pm}0.56$ and $4.30{\pm}0.79$ min, respectively. The $T_{max}$ of $^{99m}Tc$ tricarbonyl cysteine with probenecid pretreatment was $2.30{\pm}0.17$ min, whereas $T_{1/2}$ of that with probenecid pretreatment was $17.0{\pm}32.47$ min. $T_{1/2}$ of $^{99m}Tc$ tricarbonyl cysteine with probenecid pretreatment was significantly different, as compared to the result without probenecid (p<0.0001). The results showed that the excretion of $^{99m}Tc$ tricarbonyl cysteine was extremely affected by probenecid. Therefore, $^{99m}Tc$ tricarbonyl cysteine was rapidly excreted from the kidney principally by the tubular secretion.

• Bulletin of the Korean Chemical Society
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• 제27권8호
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• pp.1189-1193
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• 2006

In order to develop radiopharmaceuticals for targeting a serotonin receptor such as $5-HT_{1A}$, histidine-$C_n$-arylpiperazines (AP) (C = alkyl, n = 2, 3, 4) were prepared in five steps with yields of 25%, 37% and 51%, respectively, and radiolabeled with the $[^{99m}Tc(CO)_3(H_2O)+3]^+$. The $^{99m}Tc(CO)_3$-Histidine-Cn-APs were prepared with a high yield (>99%) and characterized as a tridentate complex with a neutral charge to pass through the blood-brain barrier (BBB). The rhenium complexes with $Re(CO)_3$ were also synthesised and comparative experiments were achieved to evaluate the nature of the $^{99m}Tc$ complexes.

• 대한방사성의약품학회지
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• 제6권2호
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• pp.75-91
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• 2020

[^99mTc]Tc-Hexamethylpropylene amine oxime (HMPAO) is currently used as a regional cerebral blood flow imaging agent for single photon emission computed tomography (SPECT). The HMPAO ligand exists in two isomeric forms: d,l and meso showing different properties in vivo. Later studies indicated that brain uptake patterns of ^99mTc-complexes formed from separated enantiomers differed. Separation of enantiomers is difficult by fractional crystallizations method. Usually, the substance is obtained in low chemical yield in a time-consuming procedure. Furthermore, the final product still contains some impurity. So we have developed new efficient route for synthesis of R,R- and S,S-HMPAO enantiomeric compounds in 6-steps. Nucleophilic substitution (S_N2) reactions of 2,2-dimethylpropane-1,3-diamine either with S- (1a) or R-methyl2-chloropropanoate (1b) were performed to produce compounds R,R- (2a) or S,S-isomer (2b) derivatives protected with benzylchloroformate (Cbz), respectively. And then Weinreb amide and methylation reaction using Grignard reagent, oxime formation with ketone group and deprotectiion of Cbz group by hydrogenolysis gave S,S- (7a) or R,R-HMPAO (7b), respectively. Entaniomeric compounds were synthesied with high yield and purity without any undesired product. The 7a or 7b kits containing 10 ㎍ SnCl₂-2H₂O were labeled with ^99mTc with high radiolabeling yield (90%).