• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.87-90
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• 2003

Polyvinyl Alcohol(PVA)와 같이 분자간 결합력이 큰 극성고분자에 극성의 가소제를 도입하여 가역적 가소화기법을 이용하여 비결정영역뿐만 아니라 결정영역까지도 가소화시켜 연신성을 개선시키고자하는 연구가 일부 이루어져 왔다. 특히 요드는 극성고분자의 비결정 영역뿐만 아니라 결정영역까지 침투한다는 사실이 밝혀지면서 PVA의 요드 처리에 대한 연구가 많이 이루어져왔다[1-3]. 그러나 지금까지의 연구에서는 대부분 필름이나 섬유와 같이 성형가공된 상태에서, 즉 결정화가 이루어진 후에 요드화를 시켰기 때문에 그 응용범위나 연구에 있어서 한계를 지니고 있다고 할 수 있다. (중략)

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.348-349
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• 2003

PVA는 열가소성 고분자임에도 불구하고 융점(230~25$0^{\circ}C$)에 이어 바로 측쇄의 분해(270 $^{\circ}C$)가 시작되므로 공정상 많은 어려움을 가지고 있다. 그러나 요드와 같은 극성의 가소제를 사용하면 결정영역 까지도 가소화 시킬 수 있는 이점이 있어 PVA 유연성, 가공성 둥의 성질을 개선시킬 수 있다. [1-3] 특히 본 연구에서 성형 전 요드화된 폴리비닐알코올 필름을 제작하여 구조를 살펴본 결과, 결정성이 많이 감소하다가 요드흡착량이 150%의 경우에서는 무정형상태까지 나타났다. (중략)

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.3 no.2
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• pp.72-79
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• 2017

Arbutin is a hydroquinone derivative with a glucose moiety. As a tyrosinase inhibitor, it is widely used as a skin-whitening cosmetic agent for the treatment of cutaneous hyperpigmentary disorders, such as melasma and freckles. In the medical field, many studies have addressed the use of arbutin in various tumors, but the mechanism for tumor uptake of arbutin is still unclear. In this paper, we radiolabeled arbutin using radioiodine and studied its pharmacokinetics and tumor uptake via biodistribution experiments and single-photon emission computed tomography (SPECT) imaging. Radiolabeled $^{131}I-arbutin$ was stable for up to 24 h in PBS and serum. Biodistribution studies and SPECT imaging indicated high uptake of the compound in the bladder and kidneys shortly after injection. Twenty-four hours post-injection, significant deiodination was observed. Apart from high thyroid uptake, selective tumor uptake was clearly observed. The tumor-to-muscle and tumor-to-blood ratios were 26 and 9, respectively.

• Environmental Engineering Research
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• v.23 no.4
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• pp.345-353
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• 2018

This paper summarizes results of research on the electrochemical (EC) degradation of disinfection by-products (DBPs) and iodine-containing contrast media (ICMs), with the focus on EC reductive dehalogenation. The efficiency of EC dehalogenation of DBPs increases with the number of halogen atoms in an individual DBP species. EC reductive cleavage of bromine from parent DBPs is faster than that of chlorine. EC data and quantum chemical modeling indicate that the EC reduction of iodine-containing DBPs (I-DBPs) is characterized by the formation of active iodine that reacts with the organic substrate. The occurrence of ICMs has attracted attention due to their association with the generation of I-DBPs. Indirect EC oxidation of ICMs using anodes that produce reactive oxygen species can result in a complete degradation of these compounds yet I-DBPs are formed in the process. Reductive EC deiodination of ICMs is rapid and its overall rate is diffusion-controlled yet I-DBPs are also produced in this reaction. Further progress in practically feasible EC methods to remove DBPs, ICMs and other trace-level organic contaminants requires the development of novel electrocatalytic materials, elimination of mass transfer limitations via innovative design of 3D electrodes and EC reactors, and further progress in the understanding of intrinsic mechanisms of EC reactions of DBPs and TrOC at EC interfaces.

• 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.29 no.1
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• pp.105-109
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• 1995

L-3-[$^{123}I$]iodo-${\alpha}$-methyltyrosine([$^{123}I$] IMT) was synthesized by electrophilic radio-iodination using chloramine-T and Iodobead in phosphate buffered solution. And the biodistribution was examined in 9L glioma bearing rats. The radiosynthesis of [$^{123}I$]IMT with iodobead was simpler and higher in radiochemical yield(88%) than the method using chloramine-T(83%) as radioiodinating reagent. The highest yield was obtained from the reaction using 1 piece of Iodobead, $200{\mu}g$ ${\alpha}$-methyltyrosine in $100{\mu}l$ phosphate-buffered solution(pH 5.5) and the reaction was completed in 7min. 24 hours after the injection, the biodistribution in 9L glioma transplanted rats revealed the in vivo deiodination, the excretion via kidney, and 3 times higher uptake in the tumor than normal brain. These results suggest the promising clinical use of [$^{123}I$] IMT in the various malignancies.