• Journal of Radiation Protection and Research
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• v.9 no.2
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• pp.103-111
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• 1984

A convenient method of $^{99m}Tc$-methyl-ethyl-ketone (MEK) extraction technique was developed and a mobile $^{99m}Tc$-extraction generator was designed. The MEK extraction and the phase separation of $^{99m}TcO^-{_4}$ were carried out with a simple procedure in the same container. The shielding of $^{99}Mo$ radioactivity was made with one lead container. The system was simplified by shielding $^{99m}TcO_4{^-}({\gamma}_e=0.14\;MeV)$ separately. $^{99m}TcO^-{_4}\;in\;^{99m}Tc-MEK$ extract was recovered by adsorption and elution only, and therefore, the possibility of volatilization was reduced. The volume of $^{99m}TcO^{-}{_4}$-saline product was reduced to 1 ml by using a small alumina column and the column operation time was shortened. The separation time of $^{99m}Tc$ was reduced to 30 minutes, and the operation was carried out at the outside of the shielding. The system was designed to operate under the condition of bacteria-free.

• The Korean Journal of Nuclear Medicine
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• v.23 no.1
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• pp.41-48
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• 1989

$^{99m}Tc-Pertechnetate\;(TcO_4^-)$ is concentrated by the stomach after intravenous injection, allowing the detection of ectopic gastric mucosa. It has been used to develop a noninvasive test of gastric secretion. However the cellular site of concentration is still controversial, that is whether mucin-secreting epithelial cell or acid-secreting parietal cell. This study is planned to investigate the effects of cimetidine and gastric acidity on the retention of $TcO_4^-$ in the gastric wall of the rat. Also we further attempted to clarify the uptake and secreting cell of $TcO_4^-$ in the gastric mucosa. One hundred rats were divided into two groups, preliminary (40 rats) and main examination group (60 rats). Preliminary examination group was composed of fasting group (20 rats) for the detection of the time for reaching stable $TcO_4^-$ retention ratio in gastric wall and post-prandial group (20 rats) for the detection of the time for reaching the maximal gastric acidity. Main examination group was composed of fasting group (30 rats), which was subdivided into control group (10 rats), cimetidine group (10rats), $Mylanta^{(R)}$ group (10 rats) and post?prandial group (30 rats), which was subaivided into 90 min group (10 rats), 90 min cimetidine group (10 rats), and 120 min group (10 rats). Retention ratio (%) of $TcO_4$ in the gastric wall and the pH of the gastric contents were measured in the extracted stomach of the six groups. Gastric wall retention ratio of $TcO_4^-$ was calculated by the gastric wall radioactivity (cpm) divided by total gastric radioactivity (cpm) at 30 mins after intravenous injection of 0.4 mCi of $TcO_4^-$. The results were as follows: 1) The time required for reaching stable $TcO_4$ retention ratio and the lowest gastric PH were 30 min and 90 min, respectively. 2) In the fasting group, the gastric wall retention ratio of $TcO_4^-$ was significantly increased in the cimetidine group, compared with the control group (P < 0.01). However there was no significant difference between the control and $Mylanta^{(R)}$ group 3) The $TcO_4^-$ retention ratios of 90 min and 120 min groups were lower than that of the fasting control group (p < 0.05), either. After administration of cimetidine, the retention ratio was significantly increased in 90 min group (p < 0.01). 4) While $TcO_4^-$ retention ratio and gastric pH were well correlated in the post-prandial 120 min group (r=0.7112, p<0.05), in the post-prandial 90 min and 90 min cimetidine groups correlated poorly. However, there was no correlation in the three fasting groups at all. Referring the above results, we infer that $TcO_4^-$ is secreted into the gastric lumen by both parietal and non-parietal cells, with dominant non-parietal $TcO_4^-$ secretion in the fasting state and dominant parietal $TcO_4^-$ secretion in the stimulated state.

• Journal of radiological science and technology
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• v.24 no.1
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• pp.49-53
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• 2001

A number of radionuclides of interest in nuclear medicine are short lived isotopes that emit only gamma ray. The most of all Dept. of Nuclear Medicine in the hospt. are using the $^{99}Mo-^{99m}Tc$ generator for elution of the short lived isotope $^{99m}TcO_4$. A $^{99}Mo-^{99m}Tc$ generator consists of an alumina column on which $^{99}Mo$ is bound. The parent isotope($^{99}Mo$ : half life 67 hr.) decays to its daughter $^{99m}TcO_4^-$ which is a different element with a shorter half-life. $^{99}Mo$ emitted 41-keV(1.3%), 141-keV(5.6%) 181-keV(6.6%) and 366-keV(1.5%) gamma rays. But $^{99m}TcO_4$ emitted only 140-keV gamma ray. We study about the gamma ray distribution around the $^{99}Mo$ generator. And obtained the result as follows ; 1. Total counted gamma ray from generator smaller in front side than back. 2. The gamma ray emitted from $^{99}Mo$ generator without $^{99m}TcO_4$ vial increased in the back side(Mo column posited side) 3. The gamma ray only from the $^{99m}TcO_4$ vial increased in the front side. 4. Apron can protect gamma ray above 60% of total radiation from the $^{99}Mo$ generator.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.3
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• pp.177-185
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• 2006

Purpose: Purpose of this study is to synthesize $^{99m}Tc$-labeled transferrin for injection imaging and to compare it with $^{67}Ga$-titrate for the detection of infectious foci. Materials and methods: Succinimidyl 6-hydrazino-nicotinate hydrochloride-chitosan-transferrin (Transferrin) was synthesized and radiolabeled with $^{99m}Tc$. Labeling efficiencies of $^{99m}Tc$-Transferrin were determined at 10 min, 30 min, 1 hr, 2 hr, 4 hr and 8 hr. Biodistribution and imaging studies with $^{99m}Tc$-Transferrin and $^{67}Ga$-citrate were performed in a rat abscess model induced with approximately $2{\times}10^8$ colony forming unit of Staphylococcus aureus ATCC 25923. Results: Successful synthesis of Transferrin was confirmed by mass spectrometry. Labeling efficiency of $^{99m}Tc$-Transferrin was $96.2{\pm}0.7%,\;96.4{\pm}0.5%,\;96.6{\pm}1.0%,\;96.9{\pm}0.5%,\;97.0{\pm}0.7%\;and\;95.5{\pm}0.7%$ at 10 min, 30 min, 1 hr, 2 hr, 4 hr and 8 hr, respectively. The injected dose per tissue gram of $^{99m}Tc$-Transferrin was $0.18{\pm}0.01\;and\;0.18{\pm}0.01$ in the lesion and $0.05{\pm}0.01\;and\;0.04{\pm}0.01$ in the normal muscle, and lesion-to-normal muscle uptake ratio was $3.7{\pm}0.6\;and\;4.7{\pm}0.4$ at 30 min and 3 hr, respectively. On image, lesion-to-background ratio of $^{99m}Tc$-Transferrin was $2.18{\pm}0.03,\;2.56{\pm}0.11,\;3.08{\pm}0.18,\;3.77{\pm}0.17,\;4.70{\pm}0.45\;and\;5.59{\pm}0.40$ at 10 min, 30 min, 1 hr, 2 hr, 4 hr and 10 hr and those of $^{67}Ga$-citrate was $3.06{\pm}0.84,\;4.12{\pm}0.54\;and\;4.55{\pm}0.74 $ at 2 hr, 24 hr and 48 hr, respectively. Conclusion: Transferrin is successfully labeled with $^{99m}Tc$, and its labeling efficiency was higher than 95% and stable for 8 hours. $^{99m}Tc$-Transferrin scintigraphy showed higher image quality in shorter time compared to $^{67}Ga$-citrate image. $^{99m}Tc$-transferrin is supposed to be useful in the detection of the infectious foci.

• Analytical Science and Technology
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• v.11 no.5
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• pp.341-346
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• 1998

2-Pyridinecarboxaldehyde thiocarbohydrazone(PyTC) have been reacted with $Cu^{2+}$ to form $[Cu(PyTC)H_2O)]SO_4$. This complex is soluble in water and polar organic solvents. The complex has been characterized by elemental analysis, conductivity, effective magnetic moment, and spectroscopic data. From the results the complex is square planar. The colorimetric determination of Cu(II) ion by using PyTC as a ligand was studied. The solution of copper(II) with PyTC was obeyed Beer's law in concentration up to $2.9{\times}10^{-4}M$ at pH 4.

• The Korean Journal of Nuclear Medicine Technology
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• v.18 no.2
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• pp.68-72
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• 2014

Purpose The nuclear medicine examination, there is a difficulty to carry out the inspection of both on the day of residual isotope due to the half-life. In this study, by studying the mutual influence and $^{18}F$-FDG of $^{99m}TcO_4{^-}$, I would like to explain the matters to be considered in the case of performing the same day. Materials and Methods With the NEMA-1994 Phantom, and experiments were performed 3 times. Create a 1: 4 Background ratio HOT and the $^{99m}TcO_4{^-}$ The first experiment: After underwent SPECT in INFINIA (GE Healthcare, MI, USA), and were injected with $^{18}F$-FDG 37 MBq in the Background area, 13 once for 60 minutes under the same conditions was time Scan. Create a 1: 4 Background ratio HOT and the $^{18}F$-FDG second is: The Scan in PET/CT Discovery 600 (GE Healthcare, MI, USA), and 148 MBq after injection $^{99m}TcO_4{^-}$ the Background area, once for 60 minutes, 6 under the same conditions was time Scan. Create a 1: 4 Background ratio HOT and the $^{18}F$-FDG experiments las, increments of 296 MBq and 148 MBq the 1 Bed Scan after $^{99m}TcO_4{^-}$, was 1 Bed Scan under the same conditions. Non BKG area and HOT, I was measured comparing the Total Counts and SNR or CNR. Results Showed a significant difference in the ratio CNR of enforcement during SPECT $^{18}F$-FDG is, (p>0.05). The $^{99m}TcO_4{^-}$ was no significant difference between the SNR ratio of PET / CT at the time of the effective date (p<0.05). I got the results $^{99m}TcO_4{^-}$ that reduce the Total Counts of PET / CT scan. Conclusion If you make a PET / CT scan, may affect the test using the $^{99m}TcO_4{^-}$ up to 12 hours, when it is performed before the $^{99m}TcO_4{^-}$, does not affect the SNR and SUV, PET / CT scan I reduced the detection efficiency. The inspection of day, we'd like to recommend a way to complement the detection efficiency to increase the inspection time of PET / CT in move forward the inspection using the $^{99m}TcO_4{^-}$.

• The Korean Journal of Nuclear Medicine
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• v.20 no.2
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• pp.53-59
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• 1986

Radionuclide angiography of the liver and spleen with rapid bolus injection of 5 mCi of $^{99m}Tc-Sn-phytate$ was performed for evaluation of dynamic flow change of the liver in 5 normal subjects and 11 patients with diffuse hepatocellular diseases. And quantification of hepatic arterial index (HAI) was generated from those TACs of the liver and compared with HAI generated from hepatic TAC with injection of $^{99m}Tc-TcO_4^-$ as previously reported method by former investigators, 67 patients with diffuse hepatocellular diseases undergoing hepatic scintigraphy were also evaluated by 2 minutes-hepatosplenic scintiangiography with 5 mCi of $^{99m}Tc-phytate$ and followed injection of 7 mCi of $^{99m}Tc-TcO_4^-$. Those heaptic and splenic TACs were analysed and compared with HAIs of 99m Tc-phytate for evaluation of relative change (%) of count at 30 seconds and 1 minuite after peaks of rapid influx phase to the peaks (100%) in T ACs of $^{99m}Tc-phytate$ and at 1 minuite and 3 minuites after in 5 minuite-TAC of $^{99m}Tc-TcO_4^-$. Correlation between HAIs with $^{99m}Tc-phytate$ and $^{99m}Tc-TcO_4^-$ was highly significant (R=0,984, P=0), and there was most significant and useful correlation (R=0,708, p<0.0001) between HAI and splenic TAC generated by $^{99m}Tc-phytate$.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.6 no.1
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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.

• Journal of Surface Science and Engineering
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• v.56 no.1
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• pp.40-54
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• 2023

In this work, we synthesized a novel electrochemical sensing materials based on tetracarboxylic copper phthalocyanine (TcCuPtc) conjugated PANI (TcCuPtc@PANI). The synthesized materials were employed to modify the screen-printed carbon electrode (SPCE) for the selective sensing of 4-nitrophenol. The TcCuPtc was conjugated with conducting polymer of PANI through the electrostatic interaction and π-π electron conjugation, the polymer film of PANI to inhibit the leakage of TcCuPtc from the surface of the electrode. The prepared TcCuPtc@PANI were characterized and confirmed by scanning electron microscopy (SEM) with EDX, ATR-IR, UV-vis absorption spectroscopy, cyclic voltammetry, and differential pulse voltammetry techniques. The prepared TcCuPtc@PANI/SPCE showed an excellent electrocatalytic sensing of 4-NP in the linear concentrations from 3 to 500 nM with a LOD of 0.03 nM and a sensitivity of 8.8294 ㎂/nM cm^-2. However, the prepared TcCuPtc@PANI/SPCE showed selective sensing of 4-NP in the presence of other interfering species. The practical applicability of the TcCuPtc@PANI/SPCE was employed for the sensing of 4-NP in different water samples by standard addition method and showed satisfactory recovery results.

• The Korean Journal of Nuclear Medicine
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• v.33 no.1
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• pp.84-93
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• 1999

Purpose: We investigated the direct labeling method of antibody with $^{99m}Tc$ and $^{188}Re$ and examined the stability and function of these labeled compounds in in vitro and in vivo. Materials and Methods: Disulfide bond of nonspecific human IgG was reduced to -SH group by 2-mercaptoethanol. Stannous ion was used to reduce $^{99m}Tc$ and $^{188}Re$. The stability of $^{99m}Tc$-IgG and $^{188}Re$-IgG was estimated upto 24 hrs. Biodistribution was evaluated in abscess bearing rats at 4 and 24 hr post-injection of $^{99m}Tc$ or $^{188}Re$ labeled IgG. Results: The number of -SH group per reduced IgG molecule was 2.34. The labeling yield of $^{99m}Tc$-IgG and $^{188}Re$-IgG were 90% and 95%, respectively The stability of $^{99m}Tc$-IgG at 1, 4, 6 and 24 hr was 91%, 83%, 78%, 7% and that of $^{188}Re$-IgG at 1, 4, 16 and 24 hr was 94%, 80%, 47%, 42%, respectively. At 4 hr post-injection of $^{99m}Tc$-IgG, high uptake was found on kidney, blood, stomach and abscess ($9.42{\pm}0.68,\;1.43{\pm}0.24,\;0.86{\pm}0.18,\;0.72{\pm}0.10$ %ID/g, respectively). The uptakes at 24 hr were kidney, abscess,.itomach, and blood in descending order. In case of $^{188}Re$-lgG, high uptake at 4 hr post injection appeared on kidney, blood, abscess and stomach ($3.92{\pm}0.62,\;1.32{\pm}0.08,\;0.88{\pm}0.01,\;0.26{\pm}0.06$, respectively). The uptakes at 24 hr were kidney, abscess, blood and stomach in descending order. The abscess to blood uptake ratio of $^{99m}Tc$-IgG was 0.5 at 4 hr and 2.02 at 24 hr and that of $^{188}Re$-IgG was 0.67 and 1.29. Conclusion: $^{99m}Tc$-IgG and $^{188}Re$-IgG canbe labeled efficiently with direct labeling method. However, $^{99m}Tc$-IgG and $^{188}Re$-IgG, labeled with direct method, was unstable. Further study is needed to enhance the stability of the antibody labeling.