• Bulletin of the Korean Chemical Society
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• v.35 no.7
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• pp.2172-2174
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• 2014

• Proceedings of the Materials Research Society of Korea Conference
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• 2002.11a
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• pp.125-125
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• 2002

• Journal of the Korean Chemical Society
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• v.9 no.2
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• pp.110-112
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• 1965

The surface tension of liquid iodine was measured by differential capillary rise method at various temperatures above the melting point. A paraffin bath with mercury regulator was used to maintain constant temperature. The height of the meniscus of liquid iodine in the capillary tube was measured by a travelling microscope. The measured values of surface tensions at $125.0^{\circ},135.0^{\circ}, 145.0^{\circ}$ and $155.0^{\circ}$ were 36.88, 35.87, 34.83 and 34.04 dyne/cm, respectively. Calculated Eotvos constant from the surface tension, data. experimentally obtained, were consistent through the temperature range.

• Journal of Radiation Protection and Research
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• v.29 no.3
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• pp.173-177
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• 2004

The Chinese cabbage, being one of the principal foodstuffs in Asian countries, is tested for iodine exposure. As a radioactive source, iodine-125 of which the radiological half life is 60 days was used to measure the concentration change. Experiments were carried out four times with different times of exposure. The iodine source was prepared by the chemical reaction of NaI in order to avoid producing relatively large iodine which might be generated In the case of crystal evaporation. The deposition velocity was obtained from the integrated air concentration and surface concentration of the Chinese cabbage. The environmental half life was also calculated.

• Nuclear Engineering and Technology
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• v.55 no.12
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• pp.4659-4663
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• 2023

The use of iodine S values derived using the International Commission Radiological Protection (ICRP) phantoms may introduce significant bias in internal dosimetry for Koreans due to anatomical variability. In the current study, we produced an extensive dataset of Korean S values for selected five iodine radioisotopes (I-125, I-129, I131, I-133, and I-134) for use in radiation protection. To calculate S values, we implemented Monte Carlo simulations using the Mesh-type Reference Korean Phantoms (MRKPs), developed in a high-quality/fidelity mesh format. Noticeable differences were observed in S value comparisons between the Korean and ICRP reference phantoms with ratios (Korean/ICRP) widely ranging from 0.16 to 6.2. The majority of S value ratios were lower than the unity in Korean phantoms (interquartile range = 0.47-1.28; mean = 0.96; median = 0.69). The S values provided in the current study will be extensively utilized in iodine internal dosimetry for Koreans.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.4 no.2
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• pp.90-94
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• 2018

The potential health risk from inhalational exposure of diesel exhaust particulates (DEP) has gained considerable scientific interests. However, the long-term in vivo behavior of DEP have not been clearly understood due to the difficulty of accurate analysis of these substances in a living subject. We herein demonstrate a detail protocol for the preparation of radiolabeled DEP using a radioactive-iodine-tagged pyrene analog. The purified $^{125}I$-labeled pyrene ($[^{125}I]1$) was obtained with a good radiochemical yield ($32{\pm}4%$, n=3) and high radiochemical purity (>99%) from the stannylated precursor 2. Next, the purified $[^{125}I]1$ was successfully assembled into the DEP suspension in an efficient manner. The radiolabeled DEP was highly stable in a mouse serum for 7 days without significant deiodination or dissociation of $[^{125}I]1$. These results clearly indicate that the present radiolabeling method will be useful for biodistribution study of carbonaceous particulates in vivo.

• The Korean Journal of Nuclear Medicine
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• v.12 no.1
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• pp.37-40
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• 1978

Labelling auflatoxines, the potential carcinogenic compounds, by radioactive iodine has been studied. The auflatoxine-$B_1$, which is known to be the most abundant components of auflatoxines in the nature, was labelled by radioactive iodine-125 through an acid catalyst chloroamine-T procedure. The radiochemical yield was amounted to 63.6%. The chemical structure of the labelled product was proved to be 6-iodo 5-methoxy coumarine structure of auflatoxine-$B_1$ molecule by means of I.R. and N.M.R. spectroscopy. The labelled product was orally administered in a test animal (Rat) and examined the accumnulation of radioactivity in the body at the definite time interval. The accumnulation of the radioactivity was pronounced at the blood and the liver. There was no indication of the decomposition of auflatoxine-$B_1-^{125}I$ in the organs of the test animal.

• Nuclear Engineering and Technology
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• v.13 no.3
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• pp.145-152
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• 1981

Even though a lately reported method of high temperature exchange labelling of o-iodo-hippuric acid (Hippuran) in the absence of oxidizing agent was considered to be an attractive one, the exchange mechanism was somewhat unclear. In this study iodine isotope exchanges between o-iodohippuric acid (OIH) and radioiodide ($^{125}$ $I^{ }$) or between OIH and molecular radioiodine ($^{125}$ $I_2$) were carried out at two different temperatures. Rate constants and activation parameters were measured by applying a radio-paper chromatography technique. Since o-iodobenzoic acid is known as a by-product in the exchange labelling of OIH, data were also obtained for the OIB-iodide systems for comparison. The rate constant was increased in the order of OIB...$^{125}$ $I^{[-10]}$ >OIB...$^{125}$ $I_2$>OIH..$^{125}$ $I^{[-10]}$ >OIH...$^{125}$ $I_2$ and the activation parameters for OIH were generally larger than those for OIB :$\Delta$H$\neq$$_{OIH}$>$\Delta$H$\neq$$_{OIB}$, $\Delta$S$\neq$$_{OIH}$>$\Delta$S$\neq$$_{OIB}$. These results suggest that the mechanism of the high temperature exchange is predominantly nucleophilic even though some electrophilic character can also be involved depending upon reaction conditions. Such a fact may well be caused by a feasible formation of hydrogen bonding type transition state due probably to the ortho substituent effect of-CONHC $H_2$COOH. Thus, the high temperature exchange method is estimated to be quite effective for labelling Hippuran especially at a small research center where reducing agent-free $^{131}$ I is unavailable.ailable..

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.3 no.1
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• pp.44-51
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• 2017

Herein we report an efficient radiolabeling method based on a rapid condensation reaction between N-terminal cysteine and 2-cyanobenzothiazole (CBT). Radioiodination of 2-cyano-6-hydroxybenzothiazole 2 was carried out using chloramine-T to give $^{125}I$-labeled CBT ([$^{125}I$]1) with a high radiochemical yield ($90{\pm}6%$ isolated yield, n=3) and radiochemical purity (>99%). To evaluate the radiolabeling efficiency of $^{125}I$-labeled CBT, model compounds, L-cysteine and N-terminal cysteine conjugated cRGD peptide were reacted with [$^{125}I$]1 under mild conditions. The radiolabeling reactions rapidly provided the $^{125}I$-labeled products [$^{125}I$]5 and [$^{125}I$]6 with excellent radiochemical yields and radiochemical purity. Therefore, we demonstrate that [$^{125}I$]1 will be a useful prosthetic group for radioactive iodine labeling of N-terminal cysteine bearing biomolecules.

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2649-2655
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• 2010

$PKC{\delta}$-catalytic V5 Heptapeptide (FEQFLDI, FP7) interacts with heat shock protein 27 (HSP27) and inhibits HSP27-mediated resistance to cell death against various stimuli including radiation therapy. Here, we prepared radio-iodinated heptapeptide and further investigated its uptake properties in HSP27 expression cells. Peptide sequence of FP7 and a negative control peptide (WSLLEKR, QP7) was modified by substituting their C-terminus residue to tyrosine (FP6Y and QP6Y) to label radio-iodine. Iodinated peptides were confirmed by LC mass analysis with cold iodine reaction mixture. Accumulation of [$^{125}I$]iodo-FP6Y and [$^{125}I$]iodo-QP6Y in NCI-H1299 cell line, with higher level of HSP27, and NCI-H460 cell line, with lower level of HSP27, was measured by NaI(Tl) scintillation counter. The modification of substituting C-terminus residue of FP7 to tyrosine (FP6Y) did not affect its interaction with HSP27. Accumulation of [$^{125}I$]iodo-FP6Y in NCI-H1299 cells was 3 fold higher than in NCI-H460 cells. The novel radio-iodinated FP6Y would be used as a tracer for targeting HSP27 protein.