TRANSACTIONS OF TIANJIN UNIVERSITY
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2021
·Vol. 28
·期 1
·73-79
·
IF 0
Tian Pengfei,Su Jianjun,Song Yun,Ye Ruquan,Zhu Minghui
Great attention has been paid to cofacial porphyrins due to their many unique advantages over their monomeric analogs. However, their synthesis is usually complicated. In this work, a facile impregnation method for preparing heterogenized, cofacially stacked porphyrins is proposed. An anionic porphyrin is introduced as an underlayer for immobilization of cationic cobalt porphyrin via electrostatic force. The metal center of the underlying molecule contributes to the electronic structure of the upper cationic cobalt porphyrin. Screening reveals the anionic iron porphyrin to be the most efficient underlayer molecule, lowering the activation energy barrier of CO 2 electroreduction, with an improved turnover frequency by 74% to 8.0 s −1 at − 0.6 V versus RHE.
研究领域:
化学
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材料科学
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催化
✓ 已验证
DOI
Chemistry-An Asian Journal
·
2012
·Vol. 7
·期 10
·2253-2257
·
IF 4.5
Xinrui Zhou,Xian Chen,Yaqin Jin,Istvan E. Markó
Graphical A mild process for the selective oxidation of sulfides is in great demand. Therefore, probing the mechanism underlying the biological oxidation of sulfides under ambient conditions may provide valuable insights for the development of such a reaction. Based on porphyrin models of P450 enzymes, evidence of two key intermediates, Int0 and Int1 , in this reaction is provided. A mild process for the selective oxidation of sulfides is in great demand. Therefore, probing the mechanism underlying the biological oxidation of sulfides under ambient conditions may provide valuable insights for the development of such a reaction. Based on porphyrin models of P450 enzymes, evidence of two key intermediates, Int0 and Int1 , in this reaction is provided. Spectroscopic studies indicated the formation of a hydroperoxide-iron(III) species ( Int0 ) upon addition of H 2 O 2 . This intermediate proved to be highly selective for sulfoxide production. By contrast, a defined porphyrin oxoiron(IV) cation radical ( Int1 ) directly reacted with sulfoxides, leading selectively to the corresponding sulfones. Interestingly, the available sulfoxides reversibly act as a new axial ligand for Int0 forming a more active species Int0 SO . The amount of Int0 increased in the presence of alkyl, aryl, or aromatic sulfides, while Int1 formed in the absence of these sulfides. Thus, sulfoxides and sulfones would selectively form under conditions that favor the corresponding intermediates, which elucidate the biological oxidation pathway.
研究领域:
生物化学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2015
·
IF 2.729
Bowen Zhang,Yishu Wang,Meng Li,Lili Cui,Xingquan He
A novel composite consisting of poly[iron (II) tetraphenylporphyrin] (PFeTPP) and poly(sodium- p -styrenesulfonate) (PSS) modified graphene (Gr), denoted as PFeTPP/PSS-Gr, was obtained by a solvothermal method and used for the voltammetric determination of dopamine (DA). Compared with either pristine PFeTPP or PSS-Gr, the fabricated composite exhibits superior electrocatalytic activity towards the oxidation of DA. Its oxidation peak current shows a linear dependence over the DA concentration in the range from 0.1 to 40 μM, with a detection limit of 5.73 nM ( S / N = 3). Furthermore, the fabricated PFeTPP/PSS-Gr composite can detect DA in the presence of a large excess of ascorbic acid (AA) and uric acid (UA). Our proposed sensor conceivably represents a promising material for bioanalytical applications.
研究领域:
材料科学
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分析化学
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生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
ChemElectroChem
·
2016
·Vol. 3
·期 11
·1781-1786
·
IF 3.506
Xiao Huang,Yaofang Xuan,Lisiqi Xie,Bin Su
Graphical Phase-transfer catalysis : Fe III meso -tetra-(4- N -methyl-pyridyl) porphine (Fe III TMPyP) is found to catalyze oxygen reduction at the liquid/liquid interface. Based on the size-selective ion-transfer voltammetry at the nanoscopic liquid/liquid interface, the reaction is rationalized to proceed through the phase-transfer catalysis mechanism. We report an investigation of the oxygen reduction reaction (ORR) catalyzed by Fe III meso -tetra-(4- N -methyl-pyridyl) porphine (Fe III TMPyP) at the polarized water/1,2-dichloroethane (DCE) interface. Fe III TMPyP is a water soluble pentavalent cation, which has a standard Galvani transfer potential of +0.19 V at the water/DCE interface. By four-electrode cyclic voltammetry and shake-flask biphasic reactions controlled by chemical polarization at the macroscale water/DCE interface, we demonstrated that Fe III TMPyP can catalyze the reduction of O 2 by electron donors (e.g., ferrocene and 1,1′-dimethylferrocene). Further, based on voltammetry at the free-standing silica nanochannel membrane (SNM) supported nano-ITIES (interface between two immiscible electrolyte solutions) array where the transfer of Fe III TMPyP is physically blocked owing to the size-exclusion effect, we proved that the overall reaction proceeds through a phase-transfer catalysis (PTC) process, namely the heterogeneous ion transfer of Fe III TMPyP from water to DCE followed by the homogeneous catalyzed ORR in DCE.
研究领域:
化学
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电化学
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES
·
2017
·
IF 2.603
Doudou Zhang,Yu Zhao,Dandan Lan,Xiaomin Pang,Ligai Bai,Haiyan Liu,Hongyuan Yan
In this work a polymer monolithic column was fabricated within the confines of a stainless steel column (50 × 4.6 mm i.d.) via radical polymerization by using iron porphyrin and butyl methacrylate as co-monomers, ethylene glycol dimethacrylate as crosslinking agent, ethylene glycol, isopropyl alcohol and N, N-dimethylformamide as tri-porogens, benzoyl peroxide and N , N -dimethylaniline as initiators. The resulting monolithic column was characterized by elemental analysis , scanning electron microscopy, nitrogen adsorption BET surface area, and mercury intrusion porosimetry, respectively. Results showed that the homemade monolith occupied relatively uniform pore structure , low back pressure, and enhanced selectivity for proteins in complex bio-samples. The present work described a simple and efficient method for “fractionation separation” of human plasma proteins , and it is a promising separation method for complex bio-samples in proteomic research.
研究领域:
蛋白质组学
·
生物化学
✓ 已验证
DOI
PubMed
高影响因子
Foods
·
2021
·Vol. 10
·期 11
·2797
·
IF 4.35
Zhenxiao Zheng,Kai Zhu,Zhiyuan Dai
Making Antarctic krill oil into emulsion is a good way to utilize Antarctic krill, but proliferation of microorganisms cannot be ignored. H2O2is widely used in the sterilization of liquid food since its decomposition products are environmentally friendly, although residual H2O2should be removed for food safety. Adding catalase (CAT) is an effective means to do this. However, the enzyme activity center of CAT is the iron porphyrin group, which has the risk of accelerating lipid oxidation in the oil emulsion. Therefore, we hypothesized that CAT might not be suitable for the removal of H2O2in Antarctic krill oil emulsion. In this paper, Antarctic krill oil emulsion was prepared, and then the effect of CAT on the emulsion was studied through visual observation, microscopic morphology observation, turbidity and stability, particle size, and ζ-potential; finally, the mechanism of CAT destroying the emulsion was explored from the perspective of lipid oxidation. The results showed that a stable Antarctic krill emulsion was prepared using Tween-80 as the emulsifier, with the oil concentration of 1% (v/v) and the ratio of surfactant to oil phase of 1:5 (v/v). The emulsion treated with CAT had undergone demulsification, stratification, and coagulation after 2 days of incubation, while the emulsion treated with superoxide dismutase (SOD) and bovine serum albumin (BSA) changed little. In addition, the thiobarbituric acid reactive substances (TBARS) value and the content of hydroxyl radicals in the CAT group increased significantly. The preliminary research results indicated that the effect of CAT on the emulsion related to the lipid oxidation caused by the iron porphyrin group at the center of the enzyme activity. All these results indicated that CAT was not suitable for the removal of residual H2O2in Antarctic krill oil emulsion. Moreover, it is helpful to avoid the contact of Antarctic krill oil emulsion and CAT during the processing of the krill.Keywords:Antarctic krill emulsion;catalase;iron porphyrin;lipid oxidation
研究领域:
食品科学
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生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Wenze He,Yuan Zhu,Guangming Zeng,Yi Zhang,Yingrong Wang,Mingjuan Zhang,Huai Long,Wangwang Tang
Perfluorooctanoic acid (PFOA) is a persistent and bioaccumulative refractory organic pollutant, which has aroused great concern on its environmental fate. Herein, inspired by biomimetic materials, a preeminent heterogeneous catalyst, iron-porphyrin loaded biochar (Fe(TPFPP)/BC) was constructed to activate persulfate (PS) for PFOA degradation. Moreover, the existence of persistent free radicals (PFRs) on biochar could transfer electrons to iron-porphyrin and PS to directly or indirectly speed up the generation of SO 4 − · and OH·. By introducing ascorbic acid (AA) as an electronic circulation agent to maintain the concentration of PFRs, the Fe(TPFPP)/BC-PS-AA system could degrade 75.90% PFOA in 30 min, even reaching 90.88% with increasing reaction time. The effects of key factors on PFOA degradation were investigated. The reaction mechanism and degradation pathway were proposed as well. This work not only provides insights into the catalytic field by integrating biomimetic thought, but also provides an efficient method to degrade perfluorinated compounds (PFCs).
研究领域:
环境科学
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催化材料
·
污染治理
✓ 已验证
DOI
高影响因子
Food Analytical Methods
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2015
·Vol. 9
·期 5
·1180-1187
·
IF 1.956
Ma Fei,Qin Hao,Zhou Cunliu,Wang Xia,Chen Conggui,Zheng Lei
The feasibility of using multispectral imaging (MSI) technique (405–970 nm) for predicting iron porphyrin (IP) content in pork was assessed. Based on nine feature wavelengths identified by successive projections algorithm (SPA), a partial least squares regression (PLSR) calibration model was established, leading to a determination coefficient ( R
2 ) of 0.996 for the prediction set. Visualization of IP content in each pixel of the multispectral images using the prediction model offers an effective way to monitor the distribution and real-time evolution of IP content during the manufacturing process. The results revealed the potentiality of MSI technique combined with PLSR calibration analysis as a rapid and non-destructive evaluation method of IP content for the agri-food industry.
研究领域:
食品科学
·
生物化学
·
农业工程
✓ 已验证
DOI
高影响因子
BIORESOURCE TECHNOLOGY
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2020
·
IF 7.539
Meiying Yu,Qiao Yang,Xiaole Yuan,Yunfei Li,Xuepeng Chen,Yujie Feng,Jia Liu
To achieve a membrane cathode with excellent performance, iron-porphyrin (Fe(por)) was doped to boost the catalytic and permeability properties in microbial fuel cell (MFC). The membrane cathode with the optimal 0.05 g of Fe(por) (denoted as Fe(por)-0.05) had the highest current density of 10.3 A m −2 and the lowest charge transfer resistance of 12.6 ± 0.3 Ω. The ring-disk electrode (RDE) results further proved that the oxygen reduction reaction (ORR) occurred on the Fe(por)-0.05 through a direct four-electron transfer pathway. Moreover, the membrane cathode performed better permeability properties under electric filed and the Fe(por)-0.05 + E (E was electric field) obtained the lowest flux attenuation ratio of 14.1 ± 0.2%, which was related to its superior hydrophilicity and strong electrostatic repulsion force. Iron-porphyrin can simultaneously enhance the ORR activity and permeability of membrane cathode, providing a new direction for the practical application in MFCs.
研究领域:
环境科学
·
电化学
·
生物能源
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2022
·
IF 5.895
Rong Tian,Lan Zhou,Naihao Lu
The interactions between quercetin and bovine (or human) hemoglobin (Hb) were systematically investigated by fluorescence, UV–vis absorption spectroscopy, and molecular docking to demonstrate the structural mechanism by which quercetin affected the Hb redox state and stability. Quercetin could interact with the central cavity of the Hb molecule with one binding site to generate an Hb–quercetin complex, and the hydrophobic interaction played an important role in the formation of the complex. The binding constant for the Hb–quercetin complex at 298 K was observed to be 1.25 × 104 M–1. In addition, quercetin effectively inhibited Hb-induced lipid oxidation in liposomes or washed muscles, which was ascribed to the conversion to oxy-Hb and decreased hemin dissociation from met-Hb. Consistent with its lower abilities to bind Hb and scavenge free radicals, rutin (i.e., quercetin-3-rhamnosylglucsoside) did not significantly influence the redox state of Hb nor reduce hemin release from Hb, and subsequently, it less effectively inhibited Hb-induced lipid oxidation than quercetin. Altogether, the results herein provide novel insights into the antioxidant mechanism for quercetin and are beneficial to the application of natural quercetin in Hb-containing foods.
研究领域:
生物化学
·
食品科学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2022
·
IF 5.723
Kunpeng Song,Wen Dong,Cheng Tang,Zhijuan Zou,Yundang Wu
In this study, a novel and highly efficient ORR catalyst is designed via the pyrolysis of zeolitic imidazole framework-8 (ZIF-8) under the protection of hypercrosslinked iron porphyrins . Fe 3 O 4 nanoparticles with oxygen vacancies are formed in situ and promoting catalytic efficiency. Benefiting from the synergistic effect among the Fe 3 O 4 and ZIF-8 skeleton, the hybrid catalyst exhibits excellent ORR activity even surpassing commercial Pt/C. The pyrolyzation temperature is studied in detail and determined to be a crucial parameter for ORR performance. Nano-Fe 3 O 4 , which has high catalytic efficiency, is formed in situ at 800 ℃. Amorphous iron is formed at 600 ℃ and 700 ℃, and zero-valent iron is formed at 900 ℃. The content of oxygen vacancies, Fe–N, and graphite–N, which are beneficial to the ORR reaction, are all reached to a maximum at 800 ℃. This study provides a new approach to design highly active Fe 3 O 4 -based electrocatalytic materials.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Nano Research
·
2014
·Vol. 8
·期 2
·491-501
·
IF 6.963
Shen Liangliang,Zhao Lizhi,Qu Rui,Huang Fan,Gao Hongjun,An Yingli,Shi Linqi
A complex micelle as a hemoglobin functional model with the biaoactive function of reversible oxygen transfer has been constructed through the hierarchical assembly of the diblock copolymer poly(ethylene glycol)- block poly(4-vinylpyridine- co - N -heptyl-4-vinylpyridine) (PEG- b -P(4VP- co -4VPHep)), tetrakis(4-sulfonatophenyl)porphinato iron(II) (Fe(II)TPPS) and β-cyclodextrin (β-CD). The μ-oxo dimer of Fe(II)TPPS was successfully inhibited because the Fe(II)TPPS was included into the cavities of β-CDs through host-guest interaction. Fe(II)TPPS coordinated with pyridine groups functions as the active site to reversibly bind dioxygen. In adition, the host-guest inclusion (β-CD/Fe(II)TPPS) was encapsulated in the hydrophobic core of the complex micelle and tightly fixed by P4VP chains. The hydrophilic PEG blocks stretched in aqueous solution to constitute the shells which stabilize the structure of the complex micelle as well as endow the complex micelle with sufficient blood circulation time. Dioxygen can be bound to the Fe(II)TPPS located in the confined space and excellent reversibility of the binding-release process of dioxygen can be achieved. The quaternary amine N-heptyl-4-vinylpyridine can coerce abundant S 2 O 4
2− ions into the core of the complex micelle to facilitate the self-reduction process. Dioxygen adducts (Fe(II)TPPS(O 2 )) were effectively protected by the double hydrophobic barriers constructed by the cavity of the cyclodextrin and the core of the complex micelle which enhances the ability to resist nucleophilic molecules. Therefore, the rationally designed amphiphilic structure can work as a promising artificial O 2 carrier. Potentially, the complex micelle can be expected to improve the treatment of diseases linked with hypoxia.
研究领域:
生物材料学
·
仿生学
·
医学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）