• 한국환경보건학회지
• /
• 제30권2호
• /
• pp.115-122
• /
• 2004

A glassy carbon electrode(GCE) modified with nafion-DTPA (diethylene triamine-pentaacetic acid)-glycerol is used for the highly selective and sensitive determination of a trace amount of Cu(II). Various experimental parameters, which influenced the response of nafion-DTPA-glycerol modified electrode to Cu(II), are optimized. The Copper(II) is accumulated on the electrode surface by the formation of the complex in an open circuit, and the resulting surface is characterized by medium exchange, electrochemical reduction, and differential pulse voltammetry(DPV). The electrochemical response is evaluated with respect to concentration of modifier, pH and preconcentration time, quiet time, copper(II) concentration, and other variables. A linear range is obtained in the concentration range 1.0${\times}$10$^{-8}$ M-1.0${\times}$10$^{-6}$ MCu(II) with 7 min preconcentration time. The detection limit(3s) is as low as 2.36${\times}$10$^{-8}$ M (1.50 ppb).

• Bulletin of the Korean Chemical Society
• /
• 제14권5호
• /
• pp.594-598
• /
• 1993

The protonation constants of the 14-membered tetraaza macrocycles A(3,14-dimethyl-2,6,13,17-tetraazatricyclo$[l6.4.0^{1,18}.0^{7,12}]$docosane) and B(2,3,6,13,14,17-hexamethyl-2,6,13,17-tetraazatric yclo-[l6.4.$0^{1,18}.0^{7,12}$]docosane) were measured by potentiometry. The formation constants of each of these ligands with copper(II) and nickel(II) were determined by an out-of-cell spectrophotometric method. The results indicate that the per-N-methylated macrocycle B exhibits much higher selectivity for complex formation with copper(II) over nickel(II) ion than A and other related 14-membered tetraaza macrocycles. The effects of the N-and C-substituents on the basicity and the metal ion selectivity of the ligands are discussed. The synthesis and properties of copper(II) and nickel(II) complexes of B are also described.

• 한국전기전자재료학회논문지
• /
• 제16권7호
• /
• pp.622-626
• /
• 2003

We report the electrical properties of organic light emitting diodes (OLEDs) depending on the crystal structure of hole injection layer of copper(II)-phthalocyanine(CuPc) and the light irradiation the carrier mobility of copper(II)-phthalocyanine(CuPc) of light source. OLEDs were constructed with indium tin oxide(ITO)/CuPc/triphenyl-diamin(TPD)/tris-(8-hydroxyquinoline)aluminum(Alq$_3$)/Al.Photocurrent multiplication of OLEDs was varied by the heat-treatment condition of CuPc thin film and the light irradiation.

• Bulletin of the Korean Chemical Society
• /
• 제15권7호
• /
• pp.549-553
• /
• 1994

The 2-(dimethylaminomethyl)thiophene (dmamt) complexes with copper(II) chloride and bromide were prepared and characterized by optical, EPR, XPS spectroscopies and magnetic susceptibility measurements. The low-energy absorption band above 850 nm and the relatively small EPR hyperfine coupling constant ($A_{//}{\simeq}$125 G) indicate the pseudotetrahedral site symmetry around copper(II) ion both in Cu(dmamt)$Cl_2$ and Cu(dmamt)$Br_2$ complexes. The higher satellite to main peak intensity of Cu $2P_{3/2}$ core electron binding energy in XPS spectra also supports the pseudotetrahedral geometry around the copper(II) ions having $CuNSX_2$ chromophores. The distortion from square-planar to pseudotetrahedral symmetry is likely to arise from the steric hindrance of the bulky dmamt ligand in the complex. Magnetic susceptibility study shows that these compounds follow Curie-Weiss law in the temperature range of 77-300 K with positive Weiss constant exhibiting the ferromagnetic interaction between copper(II) ions in solid state.

• Journal of Microbiology and Biotechnology
• /
• 제13권3호
• /
• pp.394-399
• /
• 2003

The in vitro cytotoxic effects of newly synthesized copper (II) glycinate complex were investigated in two gastric cancer cell lines of SNU484 and SNU638 cells. The complex inhibited the growth and decreased the viability of both gastric cancer cells in a dose-dependent manner. Gastric cancer tells treated with the complex exhibited the features of apoptosis, as demonstrated by fragmentation of chromosomal DNA, activation of caspase-3-like enzyme, and cleavage of poly［ADP-ribose］ polymerase (PARP). With the treatment of copper (II) glycinate complex, the active form of caspase-3 was observed in SNU484 cells, but not in SNU638 cells, indicating that an alternative pathway of apoptosis might have been triggered in SNU638 cells. In conclusion, copper (II) glycinate complex induces apoptosis of SNU484 and SNU638 gastric cancer cells, and it is suggested that novel copper (II) glycinate complex is highly active against human gastric cancer cells.

• Bulletin of the Korean Chemical Society
• /
• 제25권6호
• /
• pp.796-800
• /
• 2004

The structure of [Cu(tpen)]$(ClO_4)_2$ (tpen = N,N,N',N'-tetrakis(2-pyridylmethyl)-1,2-ethanediamine) has been identified by X-ray crystallography. The copper(II) ion is surrounded by two amine N atoms and three pyridine N atoms of the ligand, making a distorted trigonal-bipyramid. Among the six potential N donor atoms (two amine N and four pyridine N atoms), only one pyridine N atom remains uncoordinated. We examined structural changes on addition of $Cl^-$ to $[Cu(tpen)]^{2+}$(1). The addition of $Cl^-$ in methanol resulted in the formation of a novel dinuclear copper(II) complex $[Cu_2Cl_2(tpen)](ClO_4)_2{\cdot}H_2O$. The structure of the dinuclear complex was verified by X-ray crystallography. Each copper(II) ion in the dinuclear complex showed a distorted square planar geometry with two pyridine N atoms, one amine N atom and one $Cl^-$ ion.

• Bulletin of the Korean Chemical Society
• /
• 제8권2호
• /
• pp.111-114
• /
• 1987

Temperature-dependent, solution EPR spectra of two mixed-valence copper(II)-copper(I) complexes have been simulated by using modified Bloch equations. The transition probability for the intramolecular electron transfer is determined from the simulation. The transition probabilities have been fitted to the Arrhenius equation to derive the activation energies. The transition probability also varies according to the solvent used.

• 대한화학회지
• /
• 제9권1호
• /
• pp.45-48
• /
• 1965

Stability constant, composition of copper (II)-oxamidoxime complex were determined by spectrophotometric method. The ratio of copper (II) and oxamidoxime in the above complex was 1 : 1, and its stability constant was calculated to be $2.4{\times}10^{22}$. The complex solution gave constant absorbancy between the pH range of 4.5 to 6 at 600 $m{\mu}$ in which Beer's law applicable in the concentration range of 0.3 to 2.0 ppm studied in this work. It was noted that some metals such as Fe(III), Ni(II), Co(II), U(VI) interfere copper determination by this method.

• 대한화학회지
• /
• 제36권5호
• /
• pp.709-719
• /
• 1992

이핵성 네자리 Schiff base 의 cobalt(II), nickel(II) 및 copper(II) 착물인 [Co(II)_2(TSBP)(L)_4], [Ni(II)_2(TSBP)(L)_4] 및 [Cu(II)_2(TSBP)] (TSBP: 3,3',4,4'-tetra(salicylideneimino)-1,1'-biphenyl, L: Py, DMSO 및 DMF)들을 합성하여 원소분석, IR-spectrum, UV-visible spectrum, T.G.A. 및 D.S.C.를 측정하여 이핵성 착물로 주어짐을 확인하였다. 지지전해질로서 0.1M TEAP-L (L; Py, DMSO 및 DMF)에서 1mM-착물용액의 순환전압-전류법과 D.P.P.법으로 전기화학적 성질을 측정한 결과 이핵성 cobalt(II) 착물은 일전자의 확산 지배적인 네단계의 산화-환원과정이 Co(III)_2 {^\longrightarrow \\_\longleftarrow^e^-}Co(III)Co(II)_2{^\longrightarrow \\_\longleftarrow^e^-}Co(II){^\longrightarrow \\_\longleftarrow^e^-}Co(I){^\longrightarrow \\_\longleftarrow^e^-}Co(I)_2 으로 일어나고 이핵성 nickel(II) 및 copper(II) 착물들은 일전자의 확산지배적인 두 단계의 산화-환원과정이 M(II)_2 {^\longrightarrow \\_\longleftarrow^e^-}M(I)M(I){^\longrightarrow \\_\longleftarrow^e^-}M(I)_2 (M; Ni 및 Cu)으로 일어남을 알았다.

• 대한화학회지
• /
• 제46권5호
• /
• pp.484-488
• /
• 2002