• Journal of Microbiology and Biotechnology
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• v.13 no.3
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• pp.373-377
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• 2003

Various groups of industrial and agricultural pollutants (heavy metal ions, cyanides, and pesticides) can be detected by enzymes. Since heavy metal ions inhibit urease, cyanides inhibit peroxidase, organophosphorus and carbamate pesticides inhibit butyrylcholinesterase, these enzymes were co-immobilized into a bovine serum albumin gel on the surface of an ion-sensitive field effect transistor to create a bioprobe that is sensitive to the compounds mentioned above. The sensitivity of the present sensor towards KCN corresponded to $1\;\mu\textrm{M}$ with 1 min of incubation time. The detection limits for Hg(II) ions and the pesticide carbofuran were 0.1 and $0.5\;\mu\textrm{M}$, respectively, when a 10 min sensor incubation time in contaminated samples was chosen. The total time for determining the concentrations of all species mentioned did not exceed 20 min.

• Bulletin of the Korean Chemical Society
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• v.23 no.10
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• pp.1409-1412
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• 2002

Polymeric membrane electrodes for acetate anion based on meso-(${\alpha}$,${\alpha}$,${\alpha}$,${\alpha}$)-5,10,15,20-tetrakis[2-(penta-fluorophenylurea) phenyl]porphyrin I and similar urea-functionalized porphyrins Ⅱ-Ⅳ as neutral ionophores were prepared. The membrane based on porphyrin I exhibits the best potentiometric properties in pH 6.0 rather than pH 7.0: linear stable response over a wide concentration range (6.0 ${\times}$$10^{-5}$-1.0 ${\times}$$10^{-2}$) with a slope of -59.6 mV/decade and a detection limit of log[CH3CO$O^-$] = -5.32. Selectivity coefficients obtained from the matched potential method (MPM) in pH 6.0 indicate that interferences of hydrophobic anions are very small for the membranes of porphyrins I and II having the strong withdrawing group. The electronic effect of urea-functionalized porphyrins and pH effect of buffer solutions are discussed on the potentiometric response.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.401.1-401.1
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• 2002

Potentiometric sensors are important and viable devices for use in pharmaceutical analysis. liquid polymeric membrane electrodes for many basic drugs and a few acidic drug were reported. The acidic drug-metal(Ⅱ)-triethylene tetramine ion pair complexes were prepared and used in poly(vinyl chloride) membrane electrodes to analyze anionic drugs such as mefenamic acid and ibuprofen. Metal ion used were Fe2＋. Co2＋. Ni2＋ and Cu2＋. Plasticizer used was o-nitrophenyl octyl ether.. (omitted)

• Journal of the Korean Chemical Society
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• v.26 no.5
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• pp.265-273
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• 1982

The effect of ${\pi}$ bonds on the calculated dipole moments for square planar and tetrahedral [M(II)$O_2S_2$]] type complexes has been investigated by two different approaches. One is the approximate molecular orbital method based on the assumption that the mixing coefficient CM of the valence basis sets for the central metal ion and the appropriate ligand orbitals is equal for all ${\sigma}$ and ${\pi}$ bonding molecular orbitals. The other is the more refined calculation based on the semiempirical LCAO-MO method. If ${\sigma}$ bonds only are assumed to be formed, the calculated dipole moments for square planar and tetrahedral complexes are lower than those of the experimental values. If the contribution of ${\pi}$ bonds to the calculated dipole moments are fully considered, the calculated dipole moments for both square planar and tetrahedral [M(II)$O_2S_2$]] type complexes are higher than the experimental values. However if ${\pi}$ bonds are assumed to be delocalzed, the calculated dipole moments for tetrahedral [M(II$O_2S_2$]] type complexes fall in the range of the experimental values, but those for square planar complexes deviate from the experimental values. These results suggest that [M(II)$O_2S_2$]] type complexes may have the tetrahedral structure in inert solvent solution. This structure is in agreement with the experimental one. The calculated dipole moments for tetrahedral [M(II)$O_2S_2$]] type complexes indicate that the contribution of ${\pi}$ bonds to the calculated dipole moments may not be neglected.

• Bulletin of the Korean Chemical Society
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• v.33 no.5
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• pp.1581-1585
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• 2012

Two pyridinecarboxamide dicyanidecobalt(III) building blocks and two mononuclear seven-coordinated macrocycle manganese(II) compounds have been rationally selected to assemble cyanide-bridged heterobimetallic complexes, resulting in three cyanide-bridged $Co^{III}-Mn^{II}$ complexes. Single X-ray diffraction analysis show that these complexes $\{[Mn(L^1)][Co(bpb)]\}ClO_4{\cdot}CH_3OH{\cdot}0.5H_2O$ ($\mathbf{1}$), $\{[Mn(L^2)][Co(bpb)]\}ClO_4{\cdot}0.5CH_3OH$ ($\mathbf{2}$) and ${[Mn(L^1)][Co(bpb)]\}ClO_4{\cdot}H_2O$ ($\mathbf{3}$) ($L^1$ = 3,6-diazaoctane-1,8-diamine, $L^2$ = 3,6-dioxaoctano-1,8-diamine; $bpb2^{2-}$ = 1,2-bis(pyridine-2-carboxamido)benzenate, $bpmb2^{2-}$ = 1,2-bis(pyridine-2-carboxamido)-4-methyl-benzenate) all present predictable one-dimensional single chain structures. The molecular structures of these one-dimensional complexes consists of alternating units of $[Mn(L)]^{2+}$ ($L=L^1$ or $L^2$) and $[Co(L^{\prime})(CN)2]^-$ ($L^{\prime}=bpb2^{2-}$, or $bpmb2^{2-}$), forming a cyanide-bridged cationic polymeric chain with free $ClO_4{^-}$ as the balance anion. The coordination geometry of manganese(II) ion in the three one-dimensional complexes is a slightly distorted pentagonal-bipyrimidal with two cyanide nitrogen atoms at the trans positions and $N_5$ or $N_3O_2$ coordinating mode at the equatorial plane from ligand $L^1$ or $L^2$. Investigation over magnetic properties of these complexes reveals that the very weak magnetic coupling between neighboring Mn(II) ions connected by the diamagnetic dicyanidecobalt(III) building block. A best-fit to the magnetic susceptibility of complex ${\mathbf}{1}$ leads to the magnetic coupling constants $J=-0.084(3)cm^{-1}$.

• Journal of the Korean Chemical Society
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• v.24 no.2
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• pp.139-145
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• 1980

High spin iron(II) complexes of 1,4,8,11-tetraazacyclotetradecane (cyclam), a macrocyclic ligand, and 1,5,8,12-tetraazadodecane (3,2,3-tet), a noncyclic ligand, have been prepared. The reaction of low spin $[Fe(cyclam)(CH_3CN)_2](ClO_4)_2$ with chloride ion in methanol produces high-spin $[Fe(cyclam)Cl]ClO_4$. Although $[Fe(cyclam)(CH_3CN)_2](ClO_4)_2$ is low spin, $[Fe(3,2,3-tet)(CH_3CN)_2](ClO_4)_2$ isolated in the present study is high spin. This difference is explained in terms of the smaller constrictive effect exerted by the noncyclic ligand than the cyclic ligand. The isolation of $[Fe(cyclam)Cl]ClO_4$ provides evidences against the current view that the presence of either unsaturation or substituents on the macrocyclic ligands is necessary for the successful preparation of high spin five-coordinate iron (II) complexes. Reactions of $[Fe(cyclam)Cl]ClO_4\;and\;[Fe(3,2,3-tet)(CH_3CN)_2](ClO_4)_2$ with carbon monoxide yield low spin six-coordinate $[Fe(cyclam)Cl(CO)]ClO_4\;and\;[Fe(3.2,3-tet)(CH_3CN)(CO)](ClO_4)_2$, respectively.

• Membrane Journal
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• v.23 no.1
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• pp.92-99
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• 2013

In this study the nanofiltration (NF) membrane treatment of a sulfuric acid waste solutions containing copper ion ($Cu^{+2}$) discharging from the etching processes of the printed circuit board (PCB) manufacturing industry has been studied for the recycling of acid etching solution. SelRO MPS-34 4040 NF membrane from Koch company was tested to obtain the basic NF data for recycling of etching solution and separation efficiency (total rejection) of copper ion. NF experiments were carried out with a dead-end membrane filtration laboratory system. The pure water flux was increased with the increasing storage time in sulfuric acid solution and lowering pH of acid solution because of the enhancement of NF membrane damage by sulfuric acid. The permeate flux of acid solution was decreased with the increasing copper ion concentration. Total rejection of copper ion was decreased with the increasing storage time in sulfuric acid solution and copper ion concentration, and lowering the pH of acid solution. The total rejection of copper ion was decreased from initial 37% to 15% minimum value.

• Journal of the Korean Chemical Society
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• v.12 no.2
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• pp.47-50
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• 1968

Two methods for separation of the impurities from bismuth metal have been found by the use of Dowex $1{\times}4,$ anion exchange resins. The first method is that Dowex $1{\times}4$ resins are packed into the two stage columns (height of under stage is 22cm and upper stage is 3cm, and diameter of columns are 1.5cm), and the impurities of Pb(II), Ag(I) and Cu(II) are separated by the eluent of 7.5M HCl soln, Zn(II), Fe(III) by 0.5M HCl solns, and Te(IV) in the upper stage by 2M NaOH soln. Remained Au(III) in the upper stage is determined by the ignition with resins. The 2nd method is that for the separation of all the impurities simultaneously the same resins are packed into single stage column(height is 10cm and diameter is 1.5cm), and all the impurities of Pb(II), Zn(II), Cu(II), Fe(III) and Ag(I) are eluted by the eluent of 0.5M HCl soln. Separated impurities are determined by the colorimetry.

• Proceedings of the Korean Biophysical Society Conference
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• 2002.06b
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• pp.53-53
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• 2002

Inhibitory effects of Cu$\^$2＋/ on the cytochrome P450 (P450)-catalyzed reactions of liver microsomes and reconstituted systems containing purified P450 and NADPH-P450 reductase (NPR) were seen. However, Zn$\^$2＋/, Mg$\^$2＋/, Mn$\^$2＋/, Ca$\^$2＋/, and Co$\^$2＋/ had no apparent effects on the activities of microsomal P450s. Cu$\^$2＋/ inhibited the reactions catalyzed by purified P450s lA2 and 3A4 with IC$\sub$50/ values of 5.7 and 8.4 ${\mu}$M, respectively.(omitted)

• Analytical Science and Technology
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• v.9 no.4
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• pp.364-372
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• 1996

The sorption and desorption properties of U(VI), Th(IV), Zr(IV), Cu(II), Pb(II), Ni(II), Zn(II), Cd(II) and Mn(II) ions on XAD-16-[2-(2-thiazolylazo)-p-cresol](TAC) chelating resin were studied by elution method for selective separation, concentration and recovery of trace metal ions in sea water. The optimum conditions for the sorption of metal ions were examined with respect to flow rate, pH and concentration of buffer solution. The overall capacities of some metal ions on this chelating resin were 0.41mmol U(VI)/g resin, 0.55mmol Th(IV)/g resin, 0.43mmol Cu(II)/g resin, and 0.32mmol Zr(IV)/g resin, respectively. The elution order of metal ions obtained from breakthrough capacity and overall capacity at pH 5.0 was found as Th(IV)>Cu(II)>U(VI)>Zr(IV)>Pb(II)>Ni(II)>Zn(II)>Cd(II)>Mn(II). Desorption of characteristics for metal ions were investigated with desorption agents such as $HNO_3$, HCl, $HClO_4$, $H_2SO_4$, and $Na_2CO_3$. It was found that most of metal ions except Zr(IV) showed high desorption efficiency with 2M $HNO_3$. But, desorption and recovery of Zr(IV) ion were successfully performed with 1M $H_2SO_4$. The resin was applied for separation and preconcentration of trace amount of U(VI) ion from artificial sea water and the recovery of U(IV) was over 96%.