Enzymatic Radioiodination of Insulin for Radioimmunoassay Use

Awh, Ok-Doo,Kim, Jae-Rok Korean Nuclear Society 1980 Nuclear Engineering and Technology Vol.12 No.2

Insulin was labelled with $^{125}$ I using lactoperoxidase as an oxidizing agent. The reaction product was purified via two stages: a starch gel electrophoresis(SGE) and a Sephadex gel filtration (SF). Upon comparison of the labelling yields and the bindabilities of the labelled insulin to its antibody, it has been found that the enzyme method shows higher yields (50%) and the better bindability to its antibody than the conventional chloramine-T method (35%). By checking the insulin blank labelling mixture with a SGE, a paper chromatography, and a radioautography technique, a by-product in the lactoperoxidase method has been identified. The separated fractions in SGE and SF were also analyzed and discussed.

Selection of Well Labelled Insulin Fractions for Radioimmunoassay Use

Awh, Ok-Doo,Kim, Jae-Rok Korean Nuclear Society 1980 Nuclear Engineering and Technology Vol.12 No.2

Selection methods of well labelled insulin fractions based on two different criteria were compared to establish an efficient low level RIA of insulin and to elucidate the correlation between the immunoreactivity and the charcoal-adsorptivity of the radioiodine labelled insulin. The results indicated that the selection of well labelled insulin fractions by means of a charcoal-adsorption test is inappropriate. Generally, the distribution of radioactivity antibody-bindability, and charcoal-adsorptivity of the labelled insulin was not consistent with each other. Thus. the selection should be carried out for every labelling batch to get the utmost assay reliability by antibody-bindability but not by charcoal-adsorptivity. By using the well selected labelled insulin fractions based on antibody-binding, a correct assay for a reference serum was possible, and by extending the incubation time upto 96 hrs, a sharp dose response curve could be obtained even in the range of below 5 $\mu$U/ml standard insulin doses.

Methionine 이성질체들의 99mTc 착물 제조 연구

오옥두(Ok Doo Awh),장희순(Hee Soon Chang),이동선(Dong Sun Lee) 대한핵의학회 1992 핵의학 분자영상 Vol.26 No.1

N/A Tc-99m-Methionine complexes from enantiomeric and racemic methionines were prepared controlling reaction parameters such as pH and the concentration of stannous chloride. Some radiochromatographic systems were also examined to determine the labelling yields of Tc-99m complexes. The best resolutions of Tc-99m complexes were obtained at ITLC-SA developed with acetone and paper chromatography with n-butanol saturated with 0.3N HCI. In the former system, HR-Tc-99m and Tc-99m-methionine complex remained at origin, while 99mTcO4 moved with Rf value of 1.0. In latter process, HR-Tc-99m stayed at the origin, while 99mTcO4 and Tc-99m- methionine complexes moved with Rf value of 0.5. By combining of two chromatographic systems, the contents of three Tc-99m species were calculated easily. Tc-99m Labelling from enantiomeric and racemic methionines had little differences and the optimal condition was found at pH 9.00 and the molar ratio of methionine to stannous chloride od 24:1. The yields of Tc-99m complexes from D-, L-, and DL-methionines were 87.6%, 94.1%, and 97.9%, respectively. The results indicated that methionine containing relatively hydrophobic methylthio group (-SCH3) would be labelled with Tc-99m by stannous chloride method.

Balance versus Priority Controversy in Economic Development A Re - examination

오윤복 ( Yoon Bock Awh ) 한국경제학회 1964 經濟學硏究 Vol.12 No.1

123I , 99mTc 사람 비특이 IgG 및 67Ga - Citrate의 실험동물에서 염증병소 섭취율의 비교

오옥두(Ok Doo Awh),임상무(Sang Moo Lim),이종두(Jong Doo Lee),우광선(Kwang Sun Woo),정위섭(Wee Sup Chung),서용섭(Yong Sup Seo) 대한핵의학회 1992 핵의학 분자영상 Vol.26 No.1

N/A 123I has ideal half life of 13 hours, suitable 159 keV gamma energy for imaging, and easy labeling methods. In Korea Cancer Center Hospital, 123I has been produced by MC-50 cyclotron. The purpose of this study is looking for good labeling condition of 123I and 99mTc to nonspecific human polyclonal IgG, and comparing these with 67Ga-citrate in the abscess bearing mice. Human polyclonal nonspecific IgG was labeled with 0.2 M phosphate buffer added 123I by chloramine T method. Human polyclonal nonspecific IgG was labeled with 99mTc-gluconate after activation with β-mercaptoethanol. In the abscess bearing mice, the radioactivity in the abscess was higher in 24 hours than 6 hours after injection. In the abscess, 123I nonspecific IgG had higher uptake than 99mTc-IgG or 67Ga-citrate. There was no significant difference in absecess uptake of 123I-IgG among 24, 72, 120 hours abscess age. Further clinical researches with 123I-nonspecific IgG, and other immunoscintigraphies using 123I are expected.

항체의 Cyclic DTPA를 이용한 99mTc 표지시 Polymer 형성과 체내 동태 변화

오옥두(Ok Doo Awh),임상무(Sang Moo Lim),우광선(Kwang Sun Woo),정위섭(Wee Sup Cung) 대한핵의학회 1993 핵의학 분자영상 Vol.27 No.2

N/A Technetium-99m labeling method using bifunctional chelat.ing agent cyclicDTPA has been evaluated with human polyclonal nonspecific IgG. IgG was conjugated with cyclic DTPA with various molar ratio. Reduction of Tc was done with Na,S,O, with various molar excesa Labeling efficiency and identification of polymer was confirmed with HPLC using TSK4000 SW column. Polymer was purified with 100 cm Sepharose 6LB column. Cultured 1x10' Staphylococcus aureus were injected into rat thigh 24 hours later labeled 1gG was injected, and in vivo distribution was observed 4 and 24 hours thereafter. Reduction of 99mTc was optimal with the 10000-50000 times molar excess of Na2S2O4, Polymer formation increased with increasing mloar excess of cyclic DTPA to IgG. Three step labeling-labeling DTPA conjugated IgG after reduction of 99mTc-rnade more polymer than two two step labeling-simultaneous mixing DTPA conjugated IgG, 99mTc and Na2S2O4,. Tc b]ood clearance and lower uptake in the abscess and other organa. IgG conjugated with 200 times molar excess of cyclic DTPA showed slower blood clearance with 200 times molar excess of cyclic DTPA showed slower blaod clearance than that of 200 times molar excess of cyclic DTPA showed slower blood clearance than that of 20 times molar excess. In the 99mTc labeling of IgG with cyclic DTPA for the immunoscintigraphy, obtimalllabeling condition should be chosen, and effect of the ' Tc labeled IgG polymer should be considered.

Taxol의 방사면역측정을 위한 I-125 표지화합물 합성

오옥두(Ok-Doo Awh),금준섭(Jun-Sub Kum),이양호(Yang-He Lee),박용석(Yong-Serk Park),편웅범(Woong-Beum Pyun),최창운(Chang-Hoon Choi) 대한의생명과학회 1997 Biomedical Science Letters Vol.3 No.2

Taxo은 diterpenoid구조를 가진 항암제로서, 난소암과 유방암에 탁월한 효과를 보이지만 다른 항암제와 마찬가지로 독성을 가지고 있어 약물의 체내 혈중농도를 모니터링하는 것이 필요하다. 약물의 혈중농도를 모니터링하는 방법은 HPLC법, ELISA법, RIA법 등이 있으나, RIA법이 민감도 측면에서 또한 간편하다는 점에서 장점이 있다. 본 연구에서는 I-125 표지항원을 이용한 방사면역측정법을 확립하기 위해 먼저 taxol유도체를 합성하였다. 먼저 taxol의 C-13 탄소의 곁가지에 위치한 C-2’부분의 hydroxy기를 succinic anhydride와 반응시켜 2'-hemisuccinyltaxol (Ⅰ)을 합성 (반응수율: 80%)하였다. 또한 tyramine을 ¹²?I로 표지하고 gel chromatography를 통해 정제된 [¹²?I]iodotyramine (Ⅱ) (반응수율: 58%)을 얻었다. (Ⅰ)과 (Ⅱ)를 반응시켜 2’-[¹²?I]iodotyramine-hemisuccinyltaxol (Ⅲ) (반응수율: 96%)을 얻어 ¹²?I 표지창원으로 사용하였다. Taxo에 대한 항체를 획득하기 위해서 (Ⅰ)을 BSA에 접합 반응시켜 2'-hemisuccinyltaxol-BSA접한체를 합성하였으며, 이것을 토끼에 면역주사하여 anti-taxol serum을 얻었다. 이 항체에 대한 역가 검정실험에서 1:20의 회석비에서 B/F(%)가 약 40%를 보였다. 이와 같은 결과는 2-[¹²?I]iodotyramine-hemisuccinyltaxol을 표지항원으로 한 taxol의 방사면역측정 방법으로 혈청내 taxol의 농도측정이 가능함을 제시 해 준다. Taxol, an anticancer drug that has diterpenoid conformation, has been used as an effective chemotherapeutical agent in the treatment of breast and ovarian cancers. Because of its toxicity like other anticancer drugs, monitoring the taxol level in serum is important procedure during cancer therapy. The various monitoring methods using HPLC, ELISA, and RIA have been adopted, and RIA technique is known to be superior than other methods in trems of sensitivity and convenience. In this study, in order to develope taxol RIA system using ¹²?I labelled antigen, first of all we synthesized taxol derivatives. 2'-hemisuccinyltaxol was obtained with about 80% yield by esterification of taxol at C-2' hydroxyl group on C-l3 carbon with succinic anhydride. [¹²?I] iodotyramine was prepared with 58% labelling yield by radioiodination of tyramine and purified by gel chromatography. 2'-[¹²?I]iodotyramine-hemisuccinyltaxol, ¹²?I labelled antigen for taxol RIA, was synthesized with 96% yield from conjugation of 2'-hemisuccinyltaxol and [¹²?I] iodotyramine. Anti-taxol serum was produced from the rabbit immunized with 2'-hemisuccinyltaxol-BSA synthesized by 2'-hemisuccinyltaxol and BSA. The antiserum titer was determined by RIA using 2'-[¹²?I]iodotyramine-hemisuccinyltaxol. The titer of 1:20 was obtained with about 40% of B/T. The results suggest that taxol RIA using ¹²?I labelled antigen can be applied to monitor the taxol level in serum.

뇨중 삼중수소 측정

오옥두,송명재 연세대학교 보건과학연구소 1998 보건과학논집 Vol.8 No.-

T3-BSA,T4-BSA 접합체 제조 및 생성항체의 방사면역측정적 이용 연구

오옥두,김재록 대한핵의학회 1980 핵의학 분자영상 Vol.14 No.1

1) T₃-BSA 및 T₄-BSA는 Morpho CDI를 coupling agent로 사용하여 pH 5.5에서 12시간 정도 실온 하(10∼20℃)에 반응시키는 것이 효고적이며 특히 T₄의 경우는 DMF를 충분히 가해야 침전생성을 막을 수 있다. 2) 제조한 T₃-BSA 및 T₄-BSA의 접합 mole비율은 각각 8∼9:1 및 4∼5:1이었다. 이들을 사용하여 얻은 항혈청의 RIA용 적정 희석비율은 각각 1.5×104:1 및 2×103:1이었으며 교차반응성은 T₄항체가 T3항체에 비해 7∼8배 컸다. 따라서 T₄항체가가 낮게 얻어지는 이유는 T₄-BSA의 접합비율이 낮다는 사실 이외에 T₄-BSA접합체 제조, 정제, 면역등 일련의 과정에서 T₄-BSA의 T₃- BSA로의 분해에 기인한다고본다. 3) T₃나 T₄를 ester화 하지 않은채로 만든 접합체를 써서 얻은 항혈청으로도 RIA용 적정 항혈청 희석비율율에서의 교차반응영향은 무시됨으로 T₃, T₄ RIA가 가능하였다. T₃-BSA, T₄-BSA conjugates were prepared and identified spectrophotometrically. The lambda-max on the conjugates was just coincided with that of BSA, but the molar extinction coefficients of the conjugates were generally larger than that of BSA itsalf. The molar ratios of T₃:BSA and T₄:BSA in the prepared conjugates were found to be 9:1 and 5:1, respectively. The titers of the T₃ antisera were generally higher (max. 1.5×104:1) than those of T₄ (max.2×103:1), and the average cross reactivity of the T3 antibody with T₄ was lower (0.45%) than that of T4 antibody with T₃(3∼4%). The results of the study indicate that the predominant cause of the lower titers and the lower specificity of the T₄ antisera comparing with those of T₃ is mainly due to the unstability of the T₄-BSA and consequent degradation of the conjugate to T₃-BSA during preparation, purification, and even during immunization. The lower molar ratio of T₄ to BSA in the preparation stage is also considered to be a minor factor. By measuring T₃, T₄ les in the reference control serum, it has been confirmed that the prepared antisera can sufficiently be utilized, respectively, in the established radioimmunoassay systems.

Taxol의 방사면역측정을 위한 I-125 표지화합물 합성

오옥두,최창운,금준섭,박용석,이양호,편웅범 THE KOREAN SOCIETY FOR BIOMEDICAL LABORATORY SCIEN 1997 Journal of biomedical laboratory sciences Vol.3 No.2

Taxol은 diterpenoid구조를 가진 항암제로서, 난소암과 유방암에 탁월한 효과를 보이지만 다른 항암제와 마찬가지로 독성을 가지고 있어 약물의 체내 혈중농도를 모니터링하는 것이 필요하다. 약물의 혈중농도를 모니터링하는 방법은 HPLC법, ELISA법, RIA법 등이 있으나, RIA법이 민감도 측면에서 또한 간편하다는 점에서 장점이 있다. 본 연구에서는 I-125 표지항원을 이용한 방사 면역측정법을 확립하기 위해 먼저 taxol유도체를 합성하였다. 먼저 taxol의 C-13 탄소의 곁가지에 위치한 C-2'부분의 hydroxy기를 succinic anhydride와 반응시켜 2'-hemisuccinyltaxol(Ⅰ)을 합성(반응수율:80%)하였다. 또한 tyramine을 125I로 표지하고 gel chromatography를 통해 정제된 [125I]iodotyramine(Ⅱ)(반응수율:58%)을 얻었다. (Ⅰ)과 (Ⅱ)를 반응시켜 2'-[125I]iodotyramine-hemisuccinyltaxol (Ⅲ) (반응수율:96%)을 얻어 125I 표지항원으로 사용하였다. Taxol에 대한 항체를 획득하기 위해서 (Ⅰ)을 BSA에 접합반응시켜 2'-hemisuccinyltaxol-BSA접합체를 합성하였으며, 이것을 토끼에 면역주사하여 anti-taxol serum을 얻었다. 이 항체에 대한 역가 검정실험에서 1:20의 희석비에서 B/F(%)가 약 40%를 보였다. 이와 같은 결과는 2'-[125I]iodotyramine-hemisuccinyltaxol을 표지항원으로 한 taxol의 방사면역측정 방법으로 혈청내 taxol의 농도측정이 가능함을 제시해 준다. Taxol, an anticancer drug that has diterpenoid conformation, has been used as an effctive chemotherapeutical agent in the treatment of breast and ovarian cancers. Because of its toxicity like other anticancer drugs, monitoring the taxol level in serum is important procedure during cancer therapy. The various monitoring methods using HPLC, ELISA, and RIA have been adopted, and RIA technique is known to be superior than other methods in trems of sensitivity and convenience. In this study, in order to develope taxol RIA system using 125I labelled antigen, first of all we synthesized taxol derivatives. 2'-hemisuccinyltaxol was obtained with about 80% yield by esterification of taxol at C-2' hydroxyl group on C-13 carbon with succinic anhydride. [125I]iodotyramine was prepared with 58% labelling yield by radioiodination of tyramine and purified by gel chromatography. 2'-[125I]iodotyramine-hemisuccinyltaxol, 125I labelled antigen for taxol RIA, was synthesized with 96% yield from conjugation of 2'-hemisuccinyltaxol and [125I] iodotyramine. Anti-taxol serum was produced from the rabbit immunized with 2'-hemisuccinyltaxol-BSA synthesized by 2'-hemisuccinyltaxol and BSA. The antiserum titer was determined by RIA using 2'-[125I]iodotyramine-hemisuccinyltaxol. The titer of 1:20 was obtained with about 40% of B/T. The results suggest that taxol RIA using 125I labelled antigen can be applied to monitor the taxol level in serum.