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Mingming Wang, Wei Zhan
The grand scale, ultimate efficiency, and sustainability of natural photosynthesis have inspired generations of researchers in biomimetic light energy utilization. As an essential and ubiquitous component in all photosynthetic machinery, lipids and their assemblies have long been recognized as powerful molecular scaffolds in building artificial photosynthetic systems. Model lipid bilayers, such as black lipid membranes and liposomes (vesicles), have been extensively used to host natural as well as synthetic photo- and redox-active species, thereby enabling key photosynthetic processes, such as energy transfer and photoinduced electron transfer, to be examined in well-defined, natural-like membrane settings...
October 19, 2016: Accounts of Chemical Research
Pravas Deria, Jierui Yu, Rajesh P Balaraman, Jamil Mashni, Sandra N White
Highly ordered chromophoric linkers positioned within the metal-organic frameworks (MOFs) have the potential to mimic natural light-harvesting complexes. Herein we report topological control over the photophysical properties of MOFs via modular interchromophoric electronic coupling to manifest different steady-state singlet emission spectra and their corresponding fluorescence lifetimes.
October 18, 2016: Chemical Communications: Chem Comm
Young Jin Sa, Dong-Jun Seo, Jinwoo Woo, Jung Tae Lim, Jae Yeong Cheon, Seung Yong Yang, Jae Myeong Lee, Dongwoo Kang, Tae Joo Shin, Hyeon Suk Shin, Hu Young Jeong, Chul Sung Kim, Min Gyu Kim, Tae-Young Kim, Sang Hoon Joo
Iron-nitrogen on carbon (Fe-N/C) catalysts have emerged as promising non-precious metal catalysts (NPMCs) for oxygen reduction reaction (ORR) in energy conversion and storage devices. It has been widely suggested that an active site structure for Fe-N/C catalysts contains Fe-Nx coordination. However, the preparation of high-performance Fe-N/C catalysts mostly involves a high-temperature pyrolysis step, which generates not only catalytically active Fe-Nx sites, but also less active large iron-based particles...
October 18, 2016: Journal of the American Chemical Society
Guang-Yao Zhang, Yu-Hong Zhuang, Dan Shan, Guo-Fang Su, Serge Cosnier, Xueji Zhang
A simple and rapid photoelectrochemical (PEC) sensor is developed for the label-free detection of a phosphoprotein (α-casein) based on a zirconium based porphyrinic metal-organic framework (MOF), PCN-222, which exhibits an enhanced photocurrent response towards dopamine under the O2-saturated aqueous media. In this work, in terms of PEC measurements and cyclic voltammetry, the PEC behaviors of PCN-222 in aqueous media were thoroughly investigated for the first time. Additionally, in the virtue of the steric hindrance effect from the coordination of the phosphate groups and inorganic Zr-O clusters as binding sites in PCN-222, this biosensor shows high sensitivity for detecting α-casein and the limit of detection (LOD) is estimated to be 0...
October 18, 2016: Analytical Chemistry
Patrícia Manuela Ribeiro Pereira, Sandrina Silva, Mafalda Bispo, Mónica da Rocha Zuzarte, Célia Gomes, Henrique Girão, José A S Cavaleiro, Carlos A Fontes Ribeiro, Joao P C Tome, Rosa Fernandes
Here we report the rational design of a new third-generation photosensitizer (PS), a chlorin conjugated with galactodendritic units, ChlGal8, to improve the effectiveness of bladder cancer treatment. ChlGal8 shows better photo-chemical and -physical properties than a recently reported homologous porphyrin, PorGal8. In addition to inheriting excellent photostability, ability to generate singlet oxygen and to interact with the proteins galectin-1 and human serum albumin (HSA), ChlGal8 exhibits high absorption in the red region of the electromagnetic spectrum...
October 17, 2016: Bioconjugate Chemistry
Nayan Patel, Paula Pera, Penny Joshi, Mykhaylo Dukh, Walter A Tabaczynski, Kevin E Siters, Mark Kryman, Ravindra R Cheruku, Farukh Durrani, Joseph R Missert, Ramona Watson, Tymish Y Ohulchanskyy, Erin Tracy, Heinz Baumann, Ravindra K Pandey
We report herein, the synthesis and biological efficacy of near-infrared (NIR), bacteriochlorin analogs: 3-(1'-butyloxy)ethyl-3-deacetyl-bacteriopurpurin-18-N-butylimide methyl ester (3) and the corresponding carboxylic acid 10. In in vitro assays, compared to its methyl ester analog 3, the corresponding carboxylic acid derivative 10 showed higher photosensitizing efficacy. However, due to drastically different pharmacokinetics in vivo, the PS 3 (HPLC purity > 99%) showed higher tumor uptake and long-term tumor cure than 10 (HPLC purity > 96...
October 17, 2016: Journal of Medicinal Chemistry
Shinji Susa, Fumiko Sato-Monma, Kouta Ishii, Yurika Hada, Kaoru Takase, Kyoko Tada, Kiriko Wada, Wataru Kameda, Kentaro Watanabe, Toshihide Oizumi, Tamio Suzuki, Makoto Daimon, Takeo Kato
Variegate porphyria (VP) is an autosomal dominant disease caused by mutations of the protoporphyrinogen oxidase (PPOX) gene. This porphyria has unique characteristics which can induce acute neurovisceral attacks and cutaneous lesions that may occur separately or together. We herin report a 58-years-old VP patient complicated with cholelithiasis. A sequencing analysis indicated a novel c.40G>C mutation (p.G14R) in the PPOX gene. His cutaneous photosensitivity had been worsening for 3 years before the emergence of cholecystitis and it then gradually improved after cholecystectomy and ursodeoxycholic acid treatment with a slight decline in the porphyrin levels in his blood, urine and stool...
2016: Internal Medicine
Shuai Shao, Trang Nhu Do, Aida Razi, Upendra Chitgupi, Jumin Geng, Richard J Alsop, Boris G Dzikovski, Maikel C Rheinstädter, Joaquin Ortega, Mikko Karttunen, Joseph A Spernyak, Jonathan F Lovell
Computer simulations are used to design more hydrated bilayers, formed from amine-modified porphyrin-phospholipids (PoPs). Experiments confirm that the new constructs give rise to bilayers with greater water content. When chelated with manganese, amine-modified PoPs provide improved contrast for magnetic resonance and are safely used for imaging in vivo.
October 14, 2016: Small
Huabin Zhang, Jing Wei, Juncai Dong, Guigao Liu, Li Shi, Pengfei An, Guixia Zhao, Jintao Kong, Xiaojun Wang, Xianguang Meng, Jing Zhang, Jinhua Ye
Modular optimization of metal-organic frameworks (MOFs) was realized by incorporation of coordinatively unsaturated single atoms in a MOF matrix. The newly developed MOF can selectively capture and photoreduce CO2 with high efficiency under visible-light irradiation. Mechanistic investigation reveals that the presence of single Co atoms in the MOF can greatly boost the electron-hole separation efficiency in porphyrin units. Directional migration of photogenerated excitons from porphyrin to catalytic Co centers was witnessed, thereby achieving supply of long-lived electrons for the reduction of CO2 molecules adsorbed on Co centers...
October 13, 2016: Angewandte Chemie
Zheng-Dong Ding, Yu-Xia Wang, Sai-Fei Xi, Yunxing Li, Zaijun Li, Xuehong Ren, Zhi-Guo Gu
A hexagonal porphyrin-based porous organic polymer, namely, CPF-1, was constructed by 3+2 ketoenamine condensation of the C2 -symmetric porphyrin diamine 5,15-bis(4-aminophenyl)-10,20-diphenylporphyrin and 1,3,5-triformylphloroglucinol. This material exhibits permanent porosity and excellent thermal and chemical stability. CPF-1 can be employed as a superior supporting substrate to immobilize Au nanoparticles (NPs) as a result of the strong interactions between Au NPs and the CPF support. An Au@CPF-1 hybrid was synthesized by an interfacial solution infiltration method with NaBH4 as reducing agent...
October 13, 2016: Chemistry: a European Journal
Benjamin E Van Kuiken, Anselm W Hahn, Dimitrios Maganas, Serena DeBeer
Spectroscopic probes of the electronic structure of transition metal-containing materials are invaluable to the design of new molecular catalysts and magnetic systems. Herein, we show that 2p3d resonant inelastic X-ray scattering (RIXS) can be used to observe both spin-allowed and (in the V(III) case) spin-forbidden d-d excitation energies in molecular vanadium complexes. The spin-allowed d-d excitation energies determined by 2p3d RIXS are in good agreement with available optical data. In V(acac)3, a previously undetected spin-forbidden singlet state has been observed...
October 12, 2016: Inorganic Chemistry
Liangang Xiao, Song Chen, Ke Gao, Xiaobin Peng, Feng Liu, Yong Cao, Wai-Yeung Wong, Wai-Kwok Wong, Xunjin Zhu
To mimic the natural photosynthetic systems utilizing chlorophylls to absorb light and store light energy, two new porphyrin-based small molecules of PTTR and PTTCNR have been developed for photovoltaic applications. The highest power conversion efficiency of 8.21% is achieved, corresponding to a short-circuit current of 14.30 mA cm-2, open-circuit voltage of 0.82 V, and fill factor of 70.01%. The excellent device performances can be ascribed to the engineering of molecule structure and film morphology. The horizontal conjugation of 3,3''-dihexyl-terthiophene to porphyrin-core with the vertical aliphatic 2-octylundecyl peripheral substitutions, can not only effectively increase the solar flux coverage between the conventional Soret and Q bands of porphyrin unit, but also optimize molecular packing through polymorphism associated with side-chains and the linear π-conjugated backbones...
October 12, 2016: ACS Applied Materials & Interfaces
Beyza Yavuz, Zafer Yazici
In this study, antiviral effect of porphyrin was investigated. Cooper strain of Bovine Herpes Virus type 1(BoHV-1) and Kos strain of Herpes Simplex Virus type-1 (HSV-1) were used to determine the potential of porphyrins to inhibit infection in vitro (with morphological and cytopathological criteria). Apoptotic and necrotic changes were determined by using DAPI and propidium staining. The non-cytotoxic dose of porphyrin (NCD-p) was initially calculated as 312.50µg/mL on MDBK and Vero cells. The apoptotic cell (APC) count was found 10% with BoHV-1 while it was 5...
September 2016: Pakistan Journal of Pharmaceutical Sciences
Susana Arrechea, Ana Aljarilla, Pilar de la Cruz, Emilio Palomares, Ganesh D Sharma, Fernando Langa
Two new conjugated acceptor-π-donor-π-acceptor (A-π-D-π-A) porphyrins have been synthesised using 3-ethylrhodanine (1a) or dicyanovinylene (1b) groups as acceptor units. Their optical and electrochemical properties made these materials excellent electron donors along with PC71BM as the acceptor for solution-processed bulk heterojunction organic solar cells. The devices based on 1a:PC71BM (1 : 2) and 1b:PC71BM (1 : 2) processed with CB showed low power conversion efficiencies (PCE) of 2.30% and 2...
October 12, 2016: Nanoscale
Ana Rioz-Martínez, Jens Oelerich, Nathalie Ségaud, Gerard Roelfes
A novel DNA-based hybrid catalyst comprised of salmon testes DNA and an iron(III) complex of a cationic meso-tetrakis(N-alkylpyridyl)porphyrin was developed. When the N-methyl substituents were placed at the ortho position with respect to the porphyrin ring, high reactivity in catalytic carbene-transfer reactions was observed under mild conditions, as demonstrated in the catalytic enantioselective cyclopropanation of styrene derivatives with ethyl diazoacetate (EDA) as the carbene precursor. A remarkable feature of this catalytic system is the large DNA-induced rate acceleration observed in this reaction and the related dimerization of EDA...
October 12, 2016: Angewandte Chemie
Wei Jiang, Jin Yang, Ying-Ying Liu, Shu-Yan Song, Jian-Fang Ma
A porous rtl metal-organic framework (MOF) [Mn5 L(H2 O)6 ⋅(DMA)2 ]⋅5DMA⋅4C2 H5 OH (1⋅Mn) (H10 L=5,10,15,20-tetra(4-(3,5-dicarboxylphenoxy)phenyl)porphyrin; DMA=N,N'-dimethylacetamide) was synthesized by employing a new porphyrin-based octacarboxylic acid ligand. 1⋅Mn exhibits high Mn(II) density in the porous framework, providing it great Lewis-acid heterogeneous catalytic capability for the cycloaddition of CO2 with epoxides. Strikingly, 1⋅Mn features excellent catalytic activity to the cycloaddition of CO2 to epoxides, with a remarkable initial turnover frequency 400 per mole of catalyst per hour at 20 atm...
October 12, 2016: Chemistry: a European Journal
Pinghua Ling, Jianping Lei, Huangxian Ju
In this work, we designed a nanoscaled porphyrinic metal-organic framework (PorMOF) with iron porphyrin as linker and zirconium ion as node for electrochemical detection of telomerase activity. The as-prepared PorMOF was characterized with scanning electron microscopy, powder X-ray diffraction and spectroscopic techniques, and demonstrated the excellent electrocatalytic activity towards O2 reduction. Sequentially, the functionalization of PorMOF with streptavidin results in water-stable electrochemical tracer for detection of telomerase...
October 11, 2016: Analytical Chemistry
Fabian Cantu Reinhard, Mala Sainna, Pranav Upadhayay, Alex Balan, Devesh Kumar, Simonetta Fornarini, Maria Elisa Crestoni, Samuel de Visser
Cytochrome P450 enzymes are heme containing mono-oxygenases that mainly react through oxygen atom transfer. Specific features of substrate and oxidant that determine the reaction rate constant for oxygen atom transfer are still poorly understood and, therefore, we did a systematic gas-phase study on reactions by iron(IV)-oxo porphyrin cation radical structures with arenes. We present here the first results obtained by using Fourier transform-ion cyclotron resonance mass spectrometry and provide rate constants and product distributions for the assayed reactions...
October 11, 2016: Chemistry: a European Journal
Miłosz Pawlicki, Karolina Hurej, Wojciech Stawski, Lechoslaw Latos-Grazynski
A meso-N-pyrrole porphyrin converts into pi-extended porphyrin forming an indolizine-3-one motif. The indolizine-3-one frame opens a lactam subunit preserving a six membered, heterocyclic structure fused with the main macrocycle. The optical properties of formed derivatives follow the structural modifications giving the absorbance and emission eventually modulated by the NH centred modifications of the fused unit.
October 11, 2016: Chemistry, An Asian Journal
Diego Rota Martir, Gordon J Hedley, David B Cordes, Alexandra M Z Slawin, Daniel Escudero, Denis Jacquemin, Tamara Kosikova, Douglas Philp, Daniel M Dawson, Sharon E Ashbrook, Ifor D W Samuel, Eli Zysman-Colman
We present the first examples of dynamic supramolecular systems composed of cyclometalated Ir(iii) complexes of the form of [Ir(C^N)2(N^N)]PF6 (where C^N is mesppy = 2-phenyl-4-mesitylpyridinato and dFmesppy = 2-(4,6-difluorophenyl)-4-mesitylpyridinato and N^N is 4,4':2',2'':4'',4'''-quaterpyridine, qpy) and zinc tetraphenylporphyrin (ZnTPP), assembled through non-covalent interactions between the distal pyridine moieties of the qpy ligand located on the iridium complex and the zinc of the ZnTPP. The assemblies have been comprehensively characterized by a series of analytical techniques ((1)H NMR titration experiments, 2D COSY and HETCOR NMR spectra and low temperature (1)H NMR spectroscopy) and the crystal structures have been elucidated by X-ray diffraction...
October 5, 2016: Dalton Transactions: An International Journal of Inorganic Chemistry
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