• 분석과학
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• 제14권2호
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• pp.123-130
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• 2001

Perfluorinated sulfonated polymer-ethylenediamine(Nafion-en)이 화학수식된 유리탄소전극을 사용하여 Cd(II) 이온의 정량에 대해 연구하였다. Cd(II) 이온의 착화제인 ethylenediamine(en)을 nafion에 고정시켜 유리탄소전극 표면에 수식하면 이 수식전극의 en은 Cd(II) 이온과 $[Cd(en)_2]^{2+}$의 착물을 형성한다. Nafion-en이 화학수식된 유리탄소전극에서 시차펄스전압전류법에 의한 Cd(II) 이온의 환원봉우리전위는 $-0.780({\pm}0.005)V$(vs. Ag/AgCl), 측정범위는 $5.0{\times}10^{-7}-2.0{\times}10^{-5}M$, 검출한계(3s)는 $2.20{\times}10^{-7}M$이었다. Nafion-en이 화학수식된 유리탄소전극의 검출한계가 수식되지 않은 유리탄소전극에 비해 약 14배 정도 향상되었다.

• BMB Reports
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• 제56권3호
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• pp.140-144
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• 2023

While CD8⁺ cytotoxic T cells have long been considered the primary effector in controlling tumors, the involvement of CD4⁺ "helper" T cells in anti-tumor immunity has been underappreciated. The investigations of intra-tumoral T cells, fueled by the recent advances in genomic technologies, have led to a rethinking of the indirect role of CD4⁺ T cells that have traditionally been described as a "helper". Accumulating evidence from preclinical and clinical studies indicates that CD4⁺ T cells can acquire intrinsic cytotoxic properties and directly kill various types of tumor cells in a major histocompatibility complex class II (MHC-II)-dependent manner, as opposed to the indirect "helper" function, thus underscoring a potentially critical contribution of CD4⁺ cytotoxic T cells to immune responses against a wide range of tumor types. Here, we discuss the biological properties of anti-tumor CD4⁺ T cells with cytotoxic capability and highlight the emerging observations suggesting their more significant role in anti-tumor immunity than previously appreciated.

• Journal of Pharmaceutical Investigation
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• 제27권3호
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• pp.165-171
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• 1997

Ibuprofen, a nonsteroidal antiinflammatory, analgesic and antipyretic drug, has several limitations in clinical application because of low solubility in water and gastrointestinal irritation. Effect of ibuprofen/$2-Hydroxypropyl-{\beta}-cyclodextrin\;(HP{\beta}CD)$ inclusion compound on release of suppository was investigated. Complex formation was confirmed by $^{1}H-\;and\;^{13}C-NMR$ spectroscopy. The release of ibuprofen from suppository base in vitro was significantly increased by the complexation with $HP{\beta}CD$. The release of ibuprofen from hydrophilic base was faster than that from hydrophobic base. In vivo studies, the release rate of ibuprofen from suppository was accelerated after rectal administration in complex form. This results suggested that ibuprofen/$HP{\beta}CD$ complex can be practically used for suppository to have faster effect of ibuprofen with reduced side effect.

• 대한화학회지
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• 제63권1호
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• pp.29-36
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• 2019

A potentially tetradentate Schiff base ligand, 2-((2-((pyridin-2-ylmethylene)amino)ethyl)amino)ethan-1-ol (PMAE), and its cadmium(II) complex, [$Cd(PMAE)I_2$] (1), were prepared and characterized by elemental analysis, FT-IR, Raman, $^1H$ and $^{13}C$ NMR spectroscopies and single-crystal X-ray diffraction. In the crystal structure of 1, the cadmium atom has a slightly distorted square-pyramidal geometry and a $CdN_3I_2$ environment in which the PMAE acts as an $N_3$-donor. In the crystal packing of the complex, the alcohol and amine groups of the coordinated ligands participate in hydrogen bonding with iodide ions and form $R^2{_2}(14)$ and $R^2{_2}(8)$ hydrogen bond motifs, respectively. In addition to the hydrogen bonds, the crystal network is stabilized by ${\pi}-{\pi}$ stacking interactions between pyridine rings. The thermodynamic stability of the isolated ligand and its cadmium complex along with their charge distribution patterns were studied by DFT and NBO analysis.

• 대한화학회지
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• 제57권6호
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• pp.712-720
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• 2013

Microwave assisted syntheses of Zn(II), Cd(II) and Hg(II) complexes with 3-aminopyridine (3AP) and nitrite ($NO_2{^-}$) ions have been reported. The metal complexes were characterized by elemental analyses, molar conductance, IR, Far-IR, electronic, NMR ($^1H$, $^{13}C$), thermal and electron impact mass spectral studies. The spectroscopic studies reveal the composition, the nature of nitrite ligand in the complexes, electronic transitions, chemical environments of C and H atoms thermal degradation of the complexes. On the basis of characterization data, distorted tetrahedral geometry is suggested for Zn(II), Cd(II) and Hg(II) complexes. The organic ligand (3AP) and their metal complexes were screened against gram negative pathogenic bacteria and fungi in vitro. The results are compared with our previous report J. Korean Chem. Soc. 2013, 57, 341 on 4-aminopyridine and nitrite ion complexes of the same metal ions.

• 대한화학회지
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• 제62권3호
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• pp.177-180
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• 2018

• Bulletin of the Korean Chemical Society
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• 제26권11호
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• pp.1728-1734
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• 2005

The interactions of Cu(II)-meso-Tetrakis(n-N-methylpyridiniumyl)porphyrin (n = 2,3,4), respectively referred to as o-, m- and p-CuTMPyP, and DNA, poly$[d(A-T)_2]$ and poly$[d(G-C)_2]$ were investigated by circular and linear dichroism (CD and LD). In the o-CuTMPyP case, in which the rotation of the pyridinium ring is prevented, the shape of the CD spectrum when associated to DNA and poly$[d(A-T)_2]$ resembles and is characterized by a positive band at a low drug to DNA concentration ratio (R ratio) and is bisignate at a high R ratio. The former CD spectrum shape has been attributed to porphyrin that is bound monomerically outside of DNA while the latter can be attributed to those that are stacked. When o-CuTMPyP is bound to poly$[d(G-C)_2]$, the excitonic CD appeared at a relatively high R ratio. In contrast, a characteristic negative CD band in the Soret region was apparent for both m- and p-CuTMPyP when bound to DNA and poly$[d(G-C)_2]$ at the low R ratios, indicating that the porphyrin molecule intercalates. However, the DNA is bent near the intercalation site and the plane of the porphyrin molecule tilts relative to the DNA helix axis, as judged by the magnitude of the reduced LD. Various stacking patterns were identified by the shape of the CD spectrum for m- and p-CuTMPyP when bound to poly$[d(A-T)_2]$. Three species for the former complex and two for the latter complex were found which may reflect the extent of the stacking.

• 대한화학회지
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• 제52권2호
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• pp.133-139
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• 2008

고상추출 매질로 bis-(2-ethylhexyl)phthalate를 포함하는 polyvinyl chloride막을 사용하여 카드뮴의 잔유양 을 측정하기 위한 새로운 민감하고 선택적인 분광광도법을 연구하였다. Bis-(2-ethylhexyl)phthalate는 가소제로 사용되 었다. 수용액에서 Cd(II)은 색을 가진 Cd(II) - I- - MG 착체(여기서 MG는 malachite green이다). 형으로 있는 막에 의해 트랩되었고, 카드뮴 착체는 막에 농축되었다. 그린색의 막의 흡수는 분광광도법을 사용하여 629 nm에서 측정되었 다. 카드뮴 농도는 Cd(II) 농도와 25분 동안 착색후 막의 흡수 사이에 관계로 나타내는 검정곡선으로부터 계산하였다. 검정곡선은 시험용액에서 10-760 μgL-1 cadmium 범위에서 선형이었다. 3Sbl criterion의 검출한계는 1.8199 μgL-1 상 대 표준편차(RSD)는 4% (n=5).보다 적다. 제안된 방법은 Tadjan강(Sari-Iran), 에 있는 카드뮴의 잔량을 성공적으로 측 정하였다. 28.7 μgL-1의 평균 값을 얻었다.

• 분석과학
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• 제20권5호
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• pp.406-412
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• 2007

분광 광도법을 이용하여 ${\beta}$-CD와 $[Cu(dien)(sub-py)]^{2+}$ 이온 간의 복합체 형성에 관한 연구를 하였다. ${\beta}$-CD와 $Cu^{2+}$ 착물이 복합체를 형성 할 때 ${\gamma}_{max}$은 리간드에 전자 주는기($CH_3$)가 치환 된 경우는 $^2T_2{\rightarrow}^2E$로 한 곳에서, 전자 끄는기(Cl)가 치환된 경우는 $^2T_2{\rightarrow}^2E$와 MLCT에 의하여 두 곳에서 나타났다. 형성상수는 온도가 올라가면 결합에너지의 감소로 작아졌다. 모든 반응은 엔트로피의 감소를 보였으나 큰 발열반응으로 자발적 반응이었다. 치환기 상수(${\sigma}_x$)에 따른 Hammett plot 결과 좋은 직선성(${\gamma}=0.996$)을 보여 형성상수를 정량적으로 설명할 수 있었다.

• 약학회지
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• 제13권1호
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• pp.33-37
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• 1969

A new organic reagent, 1-isonicotynyl-2-furfurylidene hydrazine synthesized from isonicotinic acid hydrazid and furfural, gives yellow liquid with cadmium (II). Cadmium complex of the reagent is soluble in water with yellow coloration. The complex has a maximum absorption at 363 m${\mu}$ and molar ratio of cadmium to reagent was estimated as 1:1 by continuous variation method and slope method. Molecular extinction coefficient and apparent formation constant of this complex was spectrophotometrically determined. K=4.48 $\times$ 10$^{3}$ (Babko's method) K=1.33 $\times$ 10$^{3}$ (Anderson's method)