• 대한핵의학회지
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• 제1권1호
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• pp.83-87
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• 1967

$^{131}I$ 및 $^{125}I$를 함유(含有)하는 Hippuran, L-Thyroxine, Triiodothyronine, Rose Bengal, RISA, MAA, Triolein, Oleic acid 및 주사용(注射用) 옥소액(沃素液_의 합성방식(合成方式)과 $^{203}Hg$을 함유(含有)하는 Neohydrine의 합성방식(合成方式)을 각각(各各) 연구(硏究)하여 표지수율(標識收率) $100{\sim}60%$의 좋은 결과(結果)를 얻었다. 합성방식(合成方式)에서는 교환법(交換法), 옥화법(沃化法)을 사용(使用)하였고 특(特)히 Chloramin-T를 이용(利用)한 저온(低溫) 옥화반응(沃化反應)을 이용(利用)하였다. 합성품(合成品)의 제제법(製劑法) 및 pyrogen free 시험결과(試驗結果)를 기술(記述)하였으며 당연구소(當硏究所)에서의 제품분배(製品分配) 상황(狀況)을 보고(報告)하였다.

• Nuclear Engineering and Technology
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• 제12권2호
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• pp.81-87
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• 1980

락토퍼옥시데이즈(lactoperoxidase, LPO)를 사용하여 인슈린을 $^{125}$/I로 표지반응 시켰다. 반응생성물은 전분젤 전기영동(SGE) 과 세파덱스 젤여과(SF) 둥 두단계를 거쳐 정제하였다. 표지수율 과표지생성물의 항체에 대한 결합능으로 보아 종래의 클로라민-T법 (표지수율 약 35%)보다 효소법 (표지수율 약 50%)이 우수하였다. 인슈린의 첨가없이 LPO법으로 표지반응을 진행시킨 다음 SGE, 종이 크로마토그래피, 방사선사진술 등을 적용하여 LPO법에서의 부산물을 확인할 수 있었다. SGE와 SF에서의 분리 분별 부분에 관해서도 분석, 토의하였다.

• 대한핵의학회지
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• 제18권1호
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• pp.55-62
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• 1984

For an effective solid-phase labelling of protein with $^{125}I$, studies on the immobilization of lactoperoxidase(LPO) on the inner wall of polystyrene tubes were carried out. Labelling of bovine serum albumin(BSA) and insulin was also practiced using the LPO immobilized tubes. The immobilized enzyme of about $2.5{\mu}g/tube$ was sufficient for small scale labelling since the results of radio-paper chromatography of the labelling mixture of insulin indicated that the yields were sufficiently high(80%) even in the reactions conducted at room temperature for 60 sec. The results of the Sephadex column chromatography indicated that the labelled products were not contaminated with $LPO-^{125}I$, and the radiochemical purity of the products was more than 90%. In considering the general trend that the $^{125}I$ labelled protein obtained by using LPO maintains its intactness better than those obtained by using chloramine-T, together with the tendency of yield enhancing with increase of reactants-concentration, the LPO immobilized tube method is estimated to be one of the simple methods of labelling. The product might be applicable without further purification.

• Journal of Microbiology and Biotechnology
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• 제8권6호
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• pp.581-587
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• 1998

Essential amino acids involved in the catalytic role of the extracellular cytosine deaminase from Chromobacterium violaceum YK 391 were determined by chemical modification studies. The enzyme activity required the reduced form of Fe (II) ion, since the enzyme was inhibited by ο-phenanthroline. The enzyme activity was completely inhibited by the chemical modifiers, such as p-chloromercuribenzoate (p-CMB), p-hydroxymercuribenzoate, and chloramine-T at 1 mM each. The enzyme activity was also markedly inhibited by pyridoxal-5'-phosphate, diethyl pyrocarbonate, and phenylmethylsulfonyl fluroride at 1 mM each. The inactivation of the enzyme activity with p-CMB was reversed by a high concentration of cytosine. Furthermore, the inactivation of the enzyme activity with p-CMB was also reactivated by 1 mM dithiothreitol, 1 mM 2-mercaptoethanol, 1 mM cysteine-HCI, 10% ethyl alcohol, and 10% methyl alcohol. These results suggested that cysteine and methionine residues might be located in or near the active site of the enzyme, while lysine, histidine, and serine residues might be indirectly involved in the enzyme activity.

• 대한화학회지
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• 제11권2호
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• pp.51-55
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• 1967

放射性 沃化反應 中 分解하기 쉬운 化合物의 沃化反應으로 有用한 低溫沃化反應에 關하여 硏究하였다. Chloroamine-T를 利用한 沃化反應은 低溫에서 높은 收率로 放射性 沃化反應을 進行시킬 수 있었으며, 活性化된 芳香核이 있는 또는 이에 類似한 아미노酸, 蛋白質化合物, 各 種 Phenol類의 沃化가 不可能하였으나 二重結合化合物 및 一般化合物엔 큰 效果가 없었다. 反應收率은 $100{\sim}60%$이었으며, 各 化合物의 試藥에 對한 反應度는 親電子反應에 對한 芳香核의 反應度와 比例하는 것이었다. 反應操作을 記述하였으며 反應過程을 考察하였다.

• Bulletin of the Korean Chemical Society
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• 제33권11호
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• pp.3544-3550
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• 2012

Cetrizine dihydrochloride (CTZH) is widely used as an anti-allergic drug. Sodium N-bromo-p-toluenesulfonamide or bromamine-T (BAT) is the bromine analogue of chloramine-T (CAT) and is found to be a better oxidizing agent than CAT. In the present research, the kinetics of oxidation of CTZH with BAT in acid and alkaline media was studied at 313 K. The experimental rate laws obtained are: -d[BAT]/dt=$k[BAT][CTZH]^{0.80}[H^+]^{-0.48}$ in acid medium and -d[BAT]/dt=$k[BAT][CTZH]^{0.48}[OH^-]^{0.52}[PTS]^{-0.40}$ in alkaline medium where PTS is p-toluenesulfonamide. Activation parameters and reaction constants were evaluated. The solvent isotope effect was studied using $D_2O$. The dielectric effect is positive. The stoichiometry of the reaction was found to be 1:1 and the oxidation products were identified as 4-chlorobenzophenone and (2-piperazin-1-yl-ethoxy)-acetic acid in both media. The rate of oxidation of CTZH is faster in acid medium. Suitable mechanisms and related rate laws have been worked out.

• Clinical and Experimental Reproductive Medicine
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• 제13권1호
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• pp.29-38
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• 1986

In order to study the mechanism of follicular atresia, follicles were classified into the normal groups and the atretic ones, according to the criteria with or without corpus luteum, size of follicles, vascularization, status of granulose cells and the hypertrophy of theca layers in the porcine ovary. To estimate the binding capacity of human chorionic gonadotropin (hCG) receptor on the granulosa cells during atresia, hCG were iodinated by the chloramine-T method and then purified through the column chromatography. The concentration" of hCG receptor in each group were measured by the hCG receptor binding assay. Binding capacity in large normal follicles were 1.16%, but atretic ones were 0.45%. But in medium and small follicles (below 6mm in diameter), the binding capacity in normal follicles were 0.09%, but atretic ones were 0.05%, which was lower than those of large follicles. The present ( ) that the concentrations of hCG receptors on granulosa cells is decreased when the follicles become atretic and be used as a sort of creteria for the identification of follicles atresia.

• 대한핵의학회지
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• 제11권1호
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• pp.9-15
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• 1977

난포 자극 홀몬(hFSH)을 클로라민 티를 사용하여 방사성 요오드로 표지하였으며 평균표지수율은 대략 65%이었다. 표지홀몬을 방사면역측정용으로 사용하기 위하여 전분젤 전기영동과 젤 여과법으로 분리정제하고 그 분리정제효과를 분석한 결과 젤 여과법이 분리시간, 간편성, 항체와의 결합력등으로 보아 우수함을 알 수 있었다. 한편 유리 표지홀몬과 항체와 결합한 표지홀몬의 비율을 결정하기 위하여 이중 항체법을 크로마토 전기영동법과 비교하여 본 결과 이중항체법에 의해서만 효과적 비율결정이 가능하였다.

• 대한방사성의약품학회지
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• 제4권2호
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• pp.85-89
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• 2018

We demonstrate a detail protocol for the radiosynthesis of an $^{125}I$-labeled MSTP prosthetic group and its application to the efficient radiolabeling of human serum albumin (HSA). Radioiodination of the precursor (2) was carried out by using $[^{125}I]$NaI and chloramine T as an oxidant at room temperature for 15 min. After HPLC purification of the crude product, the purified $^{125}I$-labeled MSTP ($[^{125}I]1$) was obtained with high radiochemical yield ($73{\pm}5%$, n = 3) and excellent radiochemical purity (>99%). Site-specific reaction between ($[^{125}I]1$) and HSA gave the $^{125}I$-labeled human serum albumin ($[^{125}I]3$) with more than 99% of radiochemical yield as determined by radio-thin-layer chromatography (radio-TLC). These results clearly demonstrate that the present radiolabeling method will be useful for the efficient and convenient radiolabeling of thiol-bearing biomolecules.

• 대한방사성의약품학회지
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• 제7권2호
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• pp.113-118
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• 2021

Chitosan is a polysaccharide derived from chitin by deacetylation. Chitosan is non-toxic, biodegradable, and biocompatible, so that it can be used in wide variety of medical applications such as wound healing and antimicrobial biomaterials. It also used as dermal fillers due to its ability to inject with liquid formulations. For investigation on in vivo distribution of these chitosans, Bolton-Hunter-conjugated chitosan (Chitosan-BH) was synthesized by the reaction between the primary amino group of chitosan and N-hydroxysuccinimide ester group of Bolton-Hunter reagent. Then Chitosan-BH was radiolabeled with ¹²⁵I (Chitosan-BH-¹²⁵I) using a Chloramine-T method. The effects of each radiolabeling step on the radiolabeling yield of the final product were tested. The results showed that purification step had significant effects on the radiolabeling yield of the final product. Finally, SPECT/CT images were obtained to evaluate in vivo uptake of the radiolabeled chitosan (Chitosan-BH-¹²⁵I) in several organs. The highest uptake was found in the site of injection at 21 days post-injection. The results of this study suggest that chitosan is expected to be useful for biomaterials of dermal fillers.