• BMB Reports
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• 제29권1호
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• pp.81-87
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• 1996

The relationship of S-thiolation and oxidation of glycogen phosphorylase b and peroxidation of phosphatidyl choline liposome by xanthine oxidase (XOD), 2,2'-azobis(2-amidinopropane) hydrochloride (AAPH), and 2,2'-azobis(dimethylvaleronitrile) (AMVN)-generated free radicals was investigated, Glycogen phosphorylase b was S-thiolated in the presence of glutathione and oxidized in the absence of it by XOD, AAPH and AMVN. In XOD-initiated reaction, the rates of S-thiolation and oxidation of phosphorylase were very similar and addition of liposome to the reaction mixture showed little inhibition of the modifications. In AAPH-initiated reaction, the rate of oxidation was higher than that of S-thiolation and addition of liposome increased oxidation of the protein but had no effect on S-thiolation. In AMVN-initiated reaction, S-thiolation was higher than oxidation and addition of liposome increased S-thiolation remarkably but showed no effect on oxidation. The effect of liposome on modifications of protein in AAPH and AMVN reaction seemed to be caused by certain reactive degradation products or intermediates of liposome by free radical attack. Peroxidation of liposome was not observed in XOD-initiated reaction. Liposome was gradually peroxidized by AAPH reaction. The peroxidation was inhibited by addition of GSH and phosphorylase. Peroxidation of liposome by AMVN was extreamly fast, and was not affected by GSH and phosphorylase.

• 한국식품위생안전성학회지
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• 제13권3호
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• pp.206-212
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• 1998

Salmonella spp.의 신속한 검출을 위하여 엷은 박막형태의 수정결정을 사용하는 압전류적(piesoelectric) 항체센서 시스템을 개발하고 증류수, 완충용액, 식염용액 등의 여러 매질 중에서 보여주는 진동 특성을 검토하였다. Salmonella spp. 균 구조항원(Common structural antigen)에 대한 항체를 수정결정에 PEI pre-coating, BSA 가교화, 3-APTES silanizaition, protein A와 DTBP thiolation의 5가지 방법에 의해 고정화한 후 항체 센서의 안정성을 살펴보았다. Salmonella 균을 주입하였을 때 Salmonella 균과 수정 결정에 고정화한 항체와의 결함반응에 의해 수정결정의 질량증가와 이에 따른 진동수 감소가 나타났다. 고정화방법 중 protein A와 DTBP를 이용하여 고정화하는 방법이 센서반응을 가장 안정적이고 재현성 있게 나타내줌을 알 수 있었다. $7.45{\times}10^{7}\;CFU/ml$의 Salmonella 균을 반응 cell 내에 주입하였을 때 protein A를 이용한 고정화의 경우 80Hz, DTBP를 이용한 고정화의 경우 283 Hz의 진동수 감소가 나타났으며, 압전류적 항체센서를 이용할 경우 40분 이내에 Salmonella spp.의 검출이 가능하였다.

• Bulletin of the Korean Chemical Society
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• 제32권2호
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• pp.722-724
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• 2011

• 생체재료학회지
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• 제22권4호
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• pp.249-258
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• 2018

Background: Mucoadhesive polymers, which may increase the contact time between the polymer and the tissue, have been widely investigated for pharmaceutical formulations. In this study, we developed a new polysaccharide-based mucoadhesive polymer with thermogelling properties. Methods: Hexanoyl glycol chitosan (HGC), a new thermogelling polymer, was synthesized by the chemical modification of glycol chitosan using hexanoic anhydride. The HGC was further modified to include thiol groups to improve the mucoadhesive property of thermogelling HGC. The degree of thiolation of the thiolated HGCs (SH-HGCs) was controlled in the range of 5-10% by adjusting the feed molar ratio. The structure of the chemically modified polymers was characterized by $^1H$ NMR and ATR-FTIR. The sol-gel transition, mucoadhesiveness, and biocompatibility of the polymers were determined by a tube inverting method, rheological measurements, and in vitro cytotoxicity tests, respectively. Results: The aqueous solution (4 wt%) of HGC with approximately 33% substitution showed a sol-gel transition temperature of approximately $41^{\circ}C$. SH-HGCs demonstrated lower sol-gel transition temperatures ($34{\pm}1$ and $31{\pm}1^{\circ}C$) compared to that of HGC due to the introduction of thiol groups. Rheological studies of aqueous mixture solutions of SH-HGCs and mucin showed that SH-HGCs had stronger mucoadhesiveness than HGC due to the interaction between the thiol groups of SH-HGCs and mucin. Additionally, we confirmed that the thermogelling properties might improve the mucoadhesive force of polymers. Several in vitro cytotoxicity tests showed that SH-HGCs showed little toxicity at concentrations of 0.1-1.0 wt%, indicating good biocompatibility of the polymers. Conclusions: The resultant thiolated hexanoyl glycol chitosans may play a crucial role in mucoadhesive applications in biomedical areas.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.701-702
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• 2000

대장균에 대한 항체를 수정결정상의 금전극에 고정화하여 압전류적 항체센서 시스템을 제작하고 그 특성을 평가하였다. 그 결과, 정상상태의 센서반응을 얻는데 소요되는 시간이 20분 이내로 단축되었으며 항원 ${\cdot}$ 항체결합에 의한 진동수변화도 대단히 안정적으로 나타났다.

• 약학회지
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• 제58권6호
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• pp.371-377
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• 2014

A new series of 3-alkylthio-6-allylthio-4(or 5)-methylpyridazines (6a-e)-(7a-e) was synthesized from citraconic anhydride (1) for development of candidates possessing anticancer activity. The process involves the formation of pyridazine ring, dichlorination, monoallythiolation, and further another alkylthiolation. Compounds 6a-e, and 7a-e were prepared from 6-allylthio-3-chloro-4-methylpyridazine (4) or 6-allylthio-3-chloro-5-methylpyridazine (5) via nucleophilic substitution reaction with alkylthiol anion as nucleophile. Intermediates 4, and 5 could be converted to target pyridazines 6a-e, and 7a-e using 1~1.5 equivalent of alkylthiol at reflux temperature in methanol in the presence of sodium hydroxide. The structures of the synthetic compounds were characterized using NMR, IR, and GC-MS analyses.

• 약학회지
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• 제58권1호
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• pp.28-32
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• 2014

A new series of 3-allylthio-6-alkylthiopyridazines (3)~(12) was synthesized from dichloropyridazine (1) for development of candidates to retain anticancer activity of human breast cancer. The process involves allythiolation and alkylthiolation from 3,6-dichloropyridazine. 6-Substituted allylthiopyridazines (3)~(12) were prepared from 3-allylthiopyridazinyl chloride (2) via nucleophilic substitution with alkylthiol anion as nucleophile. 3-Allylthiopyridazinyl chloride (2) could be converted to pyridazines (3)~(11) using 1 equivalent of alkyl mercaptan at reflux temperature in methanol. 3,6-Diallylthiopyridazine (12) was synthesized from 3,6-dichloropyridazine (1) using allyl mercaptan (4 equivalent) and sodium hydroxide in methanol. Synthetic compounds were fully identified using NMR, IR, GC-MS data.

• 공업화학
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• 제30권3호
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• pp.379-383
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• 2019

The capability of detecting amyloid beta 42 ($A{\beta}42$), a biomarker of Alzheimer's disease, using a thiolated protein A-functionalized bimetallic surface plasmon resonance (SPR) chip was investigated. An optimized configuration of a bimetallic chip containing gold and silver was obtained through calculations in the intensity measurement mode. The surface of the SPR bimetallic chip was functionalized with thiolated protein A for the immobilization of $A{\beta}42$ antibody. The response of the thiolated protein A-functionalized bimetallic chip to $A{\beta}42$ in the concentration range of 50 to 1,000 pg/mL was linear. Compared to protein A without thiolation, the thiolated protein A resulted in greater sensitivity. Therefore, the thiolated protein A-functionalized bimetallic SPR chip can be used to detect very low concentrations of the biomarker for Alzheimer's disease.

• 폴리머
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• 제27권4호
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• pp.330-339
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• 2003

폴리(스티렌-co-디비닐벤젠) 수지 페닐고리의 클로로메틸화를 통해 메틸렌티올기를 도입한 수지 (I), 폴리(스티렌-co-메틸 메타아크릴레이트-co-디비닐벤젠) 공중합체의 페닐고리와 에스터기에 클로로메틸화 반응을 거쳐 각각 메틸렌티올기를 도입하여 중금속 이온들과의 배위결합에 필요한공간개념을 배려한 수지(II) 및 폴리(스티렌-co-디비닐벤젠) 수지의 페닐고리를 클로로설폰화한 후, 소디움하이드로술파이드로 티오설폰산화한 수지 (III) 등 3가지 종류의 티올계 구상형 수지들을 합성하였다. 이어, 이들 킬레이트 수지들에 대한 중금속 이온의 흡착경향을 평가한 결과, 티올기 함유 I형 킬레이트 수지는 Hg$^{2＋}$에 대해서만 선택적 흡착성을 보였고, 티올기 함유 II형 킬레이트 수지는 Hg$^{2＋}$에 대한 흡착성능이 보다 향상되었으며, Cu$^{2＋}$, Pb$^{2＋}$, C$d^{2＋}$ 및 Cr$^{3+}$ 등의 몇몇 중금속 이온들에 대해서도 약간의 흡착능을 보였다. 다른 한편으로, 친수성의 티오설폰산기 함유 III형 킬레이트 수지는 효율적 흡착체로서 Hg$^{2＋}$, Cu$^{2＋}$, Ni$^{2＋}$, Co$^{2＋}$ 및 Cr$^{3+}$ 등의 중금속 이온들은 물론, 특히 C$d^{2＋}$ 및 Pb$^{2＋}$에 높은 흡착능을 보였다.

• Journal of Biosystems Engineering
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• 제28권2호
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• pp.167-172
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• 2003

This study was performed to fabricate a batch-type SPR biosensing system using a thiolated E. coli antibody coupling, and to explore the feasibility of real-time detection of E. coii in a stagnant sample solution. In advance. “O” and “K” antigenic serotype E. coli antibodies were thiolated with sulfo-LC-SPDP and dithiothreitol, and immobilized by chemisorption in the gold surface of compact SPR sensors. When the SPR biosensor immobilized with E. coli antibody monitored a E. coli solution, it took 3 to 5 min to stabilize. The SPR biosensing system developed in this study was able to detect E. coli in the range above 10$^4$ CFU/mL at the 0.05 significant level. Also, the SPR biosensor had possibility to significantly detect E. coli in the range of 10$^2$ to 10$^4$ CFU/mL in E. coli solutions. Meanwhile, when the SPR biosensor immobilized with 5. coli antibody was cleaned with NaOH solutions, its ability to detect E. coli largely decreased due to wash-out of the immobilized antibody. In order to reuse the SPR sensor, it should be antibody-immobilized newly.