• Bulletin of the Korean Chemical Society
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• 제35권10호
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• pp.3052-3058
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• 2014

In this article, we have designed and synthesized a novel donor-${\pi}$-acceptor (D-${\pi}$-A) type porphyrin-based sensitizer (denoted UI-5), in which a carboxyl anchoring group and a 9,9-dimethyl fluorene were introduced at the meso-positions of porphyrin ring via phenylethynyl and ethynyl bridging units, respectively. Long alkoxy chains in ortho-positions of the phenyls were supposed to reduce the degree of dye aggregation, which tends to affect electron injection yield in a photovoltaic cell. The cyclic voltammetry was employed to determine the band gap of UI-5 to be 1.41 eV based on the HOMO and LUMO energy levels, which were estimated by the onset oxidation and reduction potentials. The incident monochromatic photon-to-current conversion efficiency of the UI-5 DSSC assembled with double-layer (20 nm-sized $TiO_2$/400 nm-sized $TiO_2$) film electrodes appeared lower upon overall ranges of the excitation wavelengths, but exhibited a higher value over the NIR ranges (${\lambda}$ = 650-700 nm) compared to the common reference sensitizer N719. The UI-5-sensitized cell yielded a relatively poor device performance with an overall conversion efficiency of 0.74% with a short circuit photocurrent density of $3.05mA/cm^2$, an open circuit voltage of 0.54 mV and a fill factor of 0.44 under the standard global air mass (AM 1.5) solar conditions. However, our report about the synthesis and the photovoltaic characteristics of a porphyrin-based sensitizer in a D-${\pi}$-A structure demonstrated a significant complex relationship between the sensitizer structure and the cell performance.

• Bulletin of the Korean Chemical Society
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• 제32권12호
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• pp.4247-4252
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• 2011

The porphyrin-incorporated arylether dendrimers ZnP-D1 and ZnP-D4 were investigated to discover the influence of dendritic environments for the axial ligation of pyridine and photoinduced electron transfer by methyl viologen. Absorption and fluorescence spectra of ZnP, ZnP-D1, and ZnP-D4 were measured in dichloromethane with the addition of pyridine or methyl viologen dichloride. Axial ligation of pyridine was confirmed by red-shifted absorption spectrum. The complex formation constants $K_f$ (Table 1) for axial coordination of pyridine on ZnP, ZnP-D1, and ZnP-D4 were estimated to be $4.4{\times}10^3\;M^{-1}$, $3.3{\times}10^3\;M^{-1}$, and $1.7{\times}10^3\;M^{-1}$, respectively. The photoinduced electron transfer to methyl viologen dichloride was confirmed by fluorescence quenching. Stern-Volmer constants Ksv for ZnP, ZnP-D1, and ZnP-D4 were calculated to be $2.6{\times}10^3$, $2.5{\times}10^3$, and $2.1{\times}10^3$, respectively. ZnP-D4 surrounded by 4 aryl ether dendrons shows the smallest $K_f$ and Ksv values, with comparison to ZnP and ZnP-D1.

• Bulletin of the Korean Chemical Society
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• 제27권5호
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• pp.751-754
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• 2006

• Bulletin of the Korean Chemical Society
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• 제31권9호
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• pp.2656-2664
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• 2010

We have synthesized a series of push-pull porphyrins containing both donor and acceptor substituents at the mesopositions and have examined their spectral and biological properties. The push-pull porphyrins containing both strong donor $NH_2$ and acceptor $NO_2$ at meso-positions, in which donor group condensed with the ligand, (2,6-bis(4-methylpiperazine-1-yl-methyl)-4-formlyphenol (L) to form imine linkages with porphyrin. The Schiff base ligand 5-[4-(2,6-bis(4-methylpiperazine-1-yl-methyl)-4-iminomethylphenol)phenyl]-10,15,20-tris(4-nitrophenyl) porphyrin [$an_3$(TPP)L] can be synthesized from 2,6-bis(4-methylpiperazine-1-yl-methyl)-4-formylphenol (L) and 5-(4-aminophenyl)-10, 15,20-tris(4-nitrophenyl)porphyrin. The push-pull porphyrin [$an_3$(TPP)L] was metallated to get copper, nickel and zinc complexes. The spectral, electrochemical, antibacterial, antifungal and cytotoxicity properties of all the donor- acceptor push-pull porphyrins and their complexes were characterized and studied.

• Bulletin of the Korean Chemical Society
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• 제10권1호
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• pp.39-51
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• 1989

The infrared and resonance Raman spectra are reported for nickel and zinc tetraphenylchlorins. It is found that the IR and RR spectra become more complicated compared with the corresponding porphyrin analogs due to the symmetry changes. Some vibrational parameters like the core size and the symmetry change are examined in accordance with vibrational spectra of other type of chlorins.

• Bulletin of the Korean Chemical Society
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• 제34권12호
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• pp.3727-3732
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• 2013

The interaction between metalloporphyrins and diazine tautomers was investigated using quantum chemistry method. The results showed that the metal atom in the metalloporphyrin was not coplanar with porphin ring, and zinc porphyrin has the most extent of its non-coplanar nature. The most stable complex in nine complexes was iron porphyrin. NBO analysis indicated that the interaction between the lone pair of electrons on the nitrogen atom and the unoccupied lone pair orbital of metal contributes significantly to the stability of the complexes. Through the conceptual DFT parameter and Fukui dual descriptor, the thermodynamic stability and reactivity of complexes were analyzed. The density difference function (DDF) analyzes were performed to explore the rearrangement of electronic density after the coordination interaction. NICS calculation indicated that metalloporphyrin aromaticity was reduced after the coordination interaction, and aromaticity of diazine tautomer was increased along direction vector of the coordination interaction force.

• Journal of Preventive Medicine and Public Health
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• 제32권4호
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• pp.499-504
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• 1999

Objectives : To evaluate whether a relation between blood lead and zinc proto porphyrin(ZPP) was modified by gender in Korean lead workers. Methods : A cross-sectional study was conducted with 1,304 male and 101 female subjects in 1997. The relation between blood lead and ZPP were evaluated with linear, exponential, and quadratic models. Then, the different effect of gender on the relation was examined by adding the interaction terms in the each model. Results : $Mean{\pm}SD$ of blood lead and ZPP level was different between male$(27.7{\pm}10{\mu}g/dl\;and\;51.3{\pm}23.4{\mu}g/dl)$ and female subjects$(22.5{\pm}9.2{\mu}g/dl\;and\;78.7{\pm}38.6{\mu}g/dl)$. After adjusting for possible confounders, the effect modification by gender was significant in linear$(\beta=1.119,\;p<0.001)$, exponential$(\beta=Exp(0.008),\;p<0.05)$, and quadratic model$(\beta=1.388,\;p<0.001)$. In separate analysis, a quadratic relation between blood lead and ZPP was shown in male lead workers$(\beta=0.036,\;p<0.001)$, but an exponential relation in female lead workers$(\beta=Exp(0.029), p<0.001)$. Conclusion : Our data showed that the increasing rate of ZPP in female were always higher than in male lead workers, suggesting that females were more susceptible to occupational lead exposure than males.

• 한국식품과학회지
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• 제43권6호
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• pp.754-759
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• 2011

본 연구는 세포의 사멸 및 성장변화 등의 평가에 널리 이용되는 MTT assay에서 생성된 formazan dye에 미치는 ZnPP의 영향을 조사하였다. ZnPP는 생체 내에 자연적으로 생성되거나 다양한 관련 실험에 인위적으로 첨가해주는 물질로서, MTT formazan dye의 빛에 의한 탈색을 가속화시키는 것으로 밝혀졌다. Formazan dye의 분해는 5와 $10{\mu}M$ ZnPP 존재 시 반감기를 기준하여 각각 10 및 20배 가량 가속화되었으며, 빛이 차단된 조건에서는 영향을 미치지 않았다. ZnPP 구조 중 Zn는 formazan dye의 탈색에 영향을 미치지 않았으나, porphyrin 구조와 공통적인 감광체 성질을 나타내는 MB에 의해서 ZnPP 존재 시와 유사하게 dye의 탈색을 가속화 시켰다. 이러한 ZnPP와 MB에 의한 formazan dye의 탈색반응은 NAC와 ${\beta}$-carotene에 의해 지연되었으나, BHT에 의한 저해효과는 나타나지 않았다. 본 결과는 세포 중에 존재하는 ZnPP 등의 감광체류가 MTT tetrazolium으로부터 환원된 formazan dye의 빛에 의한 신속한 분해를 유도하며, 관련 실험에서 빛의 차단 등의 조치와 함께 각별히 유의해야함을 시사한다.

• Journal of Information Display
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• 제8권2호
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• pp.15-19
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• 2007

We have studied the effect of host materials on the electrophosphorescence properties by comparing three different host materials such as tris(8-hydroxyquinoline)-aluminum (III) $(Alq_3)$, bis(8-hydroxyquinoline)-zinc (II) $(Znq_2)$, and 4,4'-N,N' dicarbazole-biphenyl (CBP) doped with a red-emissive phosphorescent dye, 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphyrin platinum (II) (PtOEP). The EL spectra show a strong red emission (peak at 650 nm) from the triplet excited state of PtOEP and a very weak emission from an electron transport layer of $Alq_3$ and a hole transport layer of N,N'-diphenyl-N,N'-bis(3-methylphenyl)-1,1-biphenyl-4,4'-diamine (TPD). We find that the triplet exciton lifetime and the quantum efficiency decrease in the order of CBP, $Alq_3$, and $Znq_2$ host materials. The results are interpreted as a poor exciton confinement in $Alq_3$, and $Znq_2$ host compared with in CBP. Therefore, it is very important for the triplet-exciton confinement in the emissive layer for obtaining a high efficiency.

• The Korean Journal of Physiology and Pharmacology
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• 제26권2호
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• pp.125-133
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• 2022

Carbon monoxide (CO) is a known gaseous bioactive substance found across a wide array of body systems. The administration of low concentrations of CO has been found to exert an anti-inflammatory, anti-apoptotic, anti-hypertensive, and vaso-dilatory effect. To date, however, it has remained unknown whether CO influences atrial natriuretic peptide (ANP) secretion. This study explores the effect of CO on ANP secretion and its associated signaling pathway using isolated beating rat atria. Atrial perfusate was collected for 10 min for use as a control, after which high atrial stretch was induced by increasing the height of the outflow catheter. Carbon monoxide releasing molecule-2 (CORM-2; 10, 50, 100 μM) and hemin (HO-1 inducer; 0.1, 1, 50 μM), but not CORM-3 (10, 50, 100 μM), decreased high stretch-induced ANP secretion. However, zinc porphyrin (HO-1 inhibitor) did not affect ANP secretion. The order of potency for the suppression of ANP secretion was found to be hemin > CORM-2 >> CORM-3. The suppression of ANP secretion by CORM-2 was attenuated by pretreatment with 5-hydroxydecanoic acid, paxilline, and 1H-[1,2,4] oxadiazolo [4,3-a] quinoxalin-1-one, but not by diltiazem, wortmannin, LY-294002, or NG-nitro-L-arginine methyl ester. Hypoxic conditions attenuated the suppressive effect of CORM-2 on ANP secretion. In sum, these results suggest that CORM-2 suppresses ANP secretion via mitochondrial K_ATP channels and large conductance Ca²⁺-activated K⁺ channels.