• International Journal of Oral Biology
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• 제42권4호
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• pp.197-201
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• 2017

A novel method for the detection of hydrogen peroxide in aqueous solution was developed via reaction between $H_2O_2$, trivalent titanium ion ($Ti^{3+}$) and 4-(2-thiazolylazo) resorcinol (TAR), resulting in a ternary complex with a maximum UV absorbance at 530 nm. The CE detection of $H_2O_2$ was fast, sensitive and cost-effective without pretreatment procedures. $H_2O_2$ was detected within 15 min at 1 to $100{\mu}M$ range with the lowest detection limit at $1.0{\mu}M$. Under the optimized CE conditions, the concentration of $H_2O_2$ in coffee or tea extract was quantitatively determined. Our results show that CE detection of the ternary complex of $H_2O_2-Ti^{3+}$-TAR has potential applications for the detection of $H_2O_2$ in aqueous sources.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2016년도 춘계학술논문요약집
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• pp.203-204
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• 2016

• 분석과학
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• 제14권1호
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• pp.59-63
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• 2001

철-디피리딜-메페남산 삼원착물을 이온교환체로, NPOE(o-nitrophenyl octyl ether)를 가소게, PVC[poly(vinyl chloride)]를 지지체로 사용한 메페남산 이온선택성막 전극을 제작하였다. 디피리딜 화합물은 2,2'-디피리딜, 4,4'-디피리딜 그리고 4,4'-디페닐-2,2'-디피리딜을 이용하였다. 이들 막전극은 pH 8.9의 붕산완충액 중에서 $10^{-5}{\sim}10^{-3}mol/L$ 농도의 메페남산에 대하여 감응전위가 -55.98, -49.47 그리고 -59.35mV/decade를 각각 나타내는 직선성이었다. 방향족 및 지방족 카복실산염의 존재는 전극의 감응에 지장을 주지 않았다.

• 응용화학
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• 제15권1호
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• pp.25-28
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• 2011

A highly sensitive spectrofluorimetric method was developed for the determination of levodopa based on the formation of a ternary complex with Eu³⁺ in the presence of ethylenediaminetetraacetic acid. It was found that this complex manifests intense fluorescence at 591 and 613 nm with excitation at 372 nm and maximum intensity was obtained at 613 nm. Under the optimum conditions, the enhanced fluorescence intensity was proportional to the concentration of levodopa over the range of 3×10^-9-2.5×10^-7 mol L^-1 with limit of detection (LOD) of 4.37×10^-10 mol L^-1. The method offers higher sensitivity and selectivity which could be effectively applied for the determination of levodopa in pharmaceutical and biological samples.

• 분석과학
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• 제9권2호
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• pp.139-144
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• 1996

발색제로 eriochrome cyanine R(ECR)을 사용하여 여러 가지 계면활성제에서 스칸듐을 분광광도법으로 정량하는 방법과 그 착물의 조성을 연구하였다. Sc(III)-ECR 착물의 흡광도와 최대 흡수 파장은 cetyltrimethylammonium bromide (CTMAB)에서 크게 변하지만, sodium dodecyl sulfate(SDS)나 Triton X-100의 계면활성제에서는 변화가 없다. $1{\times}10^{-7}{\sim}3.0{\times}10^{-6}M$ Sc(III) 을 ECR 로 정량할 때는 pH 6.5 에서 $1{\times}10^{-3}M$ ECR 5ml와 $2{\times}10^{-4}M$ CTMAB 10ml가 필요했다. Sc(III)-ECR-CTMAB, 삼성분 착물의 몰흡광계수는 610nm에서 $5.6{\times}10^5mol^{-1}cm^{-1}L$이며 검출한계는 $1.0{\times}10^{-7}M$이었다. Sc(III)-ECR-CTMAB 삼성분 착물의 조성은 1:3:1 이었다.

• 대한화학회지
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• 제49권2호
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• pp.145-149
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• 2005

• Journal of Microbiology and Biotechnology
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• 제17권2호
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• pp.369-372
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• 2007

O-Methyltransferases (OMTs), one of the ubiquitous enzymes in plants, bacteria, and humans, catalyze a methyl-transfer reaction using S-adenosylmethionine and a wide range of phenolics as a methyl donor and acceptor, respectively. Substrates for most bacterial OMTs have largely remained elusive, but recent investigation using BcOMT2, an OMT from Bacillus cereus, suggested that ortho-dihydroxyflavonoids could serve as substrates. To elucidate the functional and structural features of BcOMT2, we expressed, and purified BcOMT2, and crystallized an apoenzyme and its ternary complex in the presence of a flavonoid and S-adenosylhomocysteine. Each crystal diffracted to $1.8{\AA}$ with its space group of C2 and $P2_{1}2_{1}2_{1}$, respectively. Structural analysis of apo-BcOMT2 and its ternary complex will provide the structural basis of methyl transfer onto (iso)flavonoids in a regiospecific manner.

• 분석과학
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• 제16권4호
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• pp.333-338
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• 2003

Inclusion selectivity of a three-dimensional piperazine-ligated cyanocadmate host complex, $[Cd_x(CN)_{2x}\{HN(CH_2CH_2)_2NH\}_y]{\cdot}zG$, has been investigated for benzene (B), toluene (T), ethylbenzene (E), o- (O), m- (M), and p-xylene (P) isomers as the aromatic guest molecules. From the binary, ternary and quarternary guest mixtures of E and xylene isomer (X), the order of inclusion selectivity in the host complex is O>E>P>M. From the binary to quinary BTX mixtures, the order of preference in the complex is seen to be B>T>O${\gg}$P>M.

• 분석과학
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• 제7권3호
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• pp.277-284
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• 1994

Xylenol orange(XO)와 희토류 원소들간에 이루어진 착물에 cetylpyridium chloride (CPC), dodecyltrimethylammonium bromide(DTMAB), cetyltrimetylammonium bromide(CTMAB), Triton X-100 등의 계면활성제를 가했을 대의 흡광도 변화로부터 이들 원소를 정량하는 방법과 조성비를 연구하였다. 양이온성 계면활성제인 CTMAB가 있을 때 XO와 희토류 원소들간의 착물의 흡광도가 다른 계면활성제에서보다 더 컸다. 따라서 희토류 정량에는 이를 선택하였다. REE-XO-CTMAB 삼성분 착물은 618nm에서 최대 흡광도를 갖고 0~0.5ppm 범위에서 Beer 법칙에 따르고 몰흡광계수는 $1.5{\times}10^5mol^{-1}cm^{-1}l$이다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2001년도 추계학술대회 및 정기총회
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• pp.99-99
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• 2001

The acid-labile subunit (ALS) associates with insulin-like growth factor (IGF)-I or -II and IGF binding protein-3 (IGFBP-3) to form a 150-kD complex in the circulation. This complex is thought to regulate the serum IGFs by restricting them in the vascular system and promotes their endocrine actions. Little is known about how ALS binds to IGFBP3, which connects the IGFs to ALS. Xenopus oocyte was utilized to study the function of ALS in assembling IGFs into the ternary complexes. Xenopus oocyte was shown to correctly translate in vitro transcribed mRNAs of ALS and IGFBP3. IGFBP3 and ALS mRNAs were injected in mixture and their products were immunoprecipitated by antisera against ALS and IGFBP3. Contrary to the traditional reports that ALS interacts only with IGF-bound IGFBP3, this study shows that ALS is capable of forming a binary complex with IGFBP3 in the absence of IGF. When cross-linked by disuccinimidyl substrate, band representing ALS-IGFBP3 complex was evident on the PAGE. IGFBP3 movement was monitored according to the distribution between the hemispheres. Following a localized translation in the vegetal hemisphere, IGFBP3 was shown to remain in the vegetal half in the presence of ALS. Different from wild type IGFBP3, however, mutant IGFBP3 freely diffused into the animal half despite the presence of ALS. Taken together, this study suggests that ALS may play an important role in sequestering IGFBP3 polypeptides via the intermolecular aggregation. Studies using this heterologous model will lead to a better understanding of the IGFBP3 and ALS assembling into the ternary structure and circulating IGF system.