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1.
Dalton Trans ; 53(17): 7605-7610, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38618719

RESUMO

Developing high performance noble-metal-free electrocatalysts as an alternative to Pt-based catalysts for the oxygen reduction reaction (ORR) in energy conversion devices is highly desirable. We report herein the preparation of a coordination-polymer (CP)-derived Fe/CP/C composite as an electrocatalyst for the ORR with excellent activity and stability both in solution and in Zn-air batteries. The Fe/CP/C catalyst was obtained from the pyrolysis of an iron porphyrin Fe(TPP)Cl (5,10,15,20-tetraphenyl-21H,23H-porphyrin iron(III) chloride) grafted Zn-coordination polymer with dangling functional groups 4,4'-oxybisbenzoic acid and 4,4'-bipyridine ligands. The Fe/CP/C catalyst showed much higher ORR activity with a half-wave potential (E1/2) of 0.90 V (vs. RHE) than the Fe/C catalyst (E1/2 = 0.85 V) derived from the carbon-black-supported Fe porphyrins in 0.1 M KOH solution. When Fe/CP/C was used as the cathode electrocatalyst in Zn-air batteries (ZABs), the ZABs achieved a significantly higher open circuit voltage (OCV = 1.43 V) and maximum power density (Pmax = 142.8 mW cm-2) compared with Fe/C (OCV = 1.38 V, Pmax = 104.5 mW cm-2) and commercial 20 wt% Pt/C (OCV = 1.41 V, Pmax = 117.6 mW cm-2). Using dangling functional groups in CP to increase the loading efficiency of iron porphyrins offered a facile method to prepare high-performance noble-metal-free electrocatalysts for the ORR, which may provide promising applications to energy conversion devices.

2.
Molecules ; 27(18)2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36144746

RESUMO

Porphyrin derivatives are popular photodynamic therapy (PDT) agents; however, their typical insolubility in water has made it challenging to separate cells of organisms in a liquid water environment. Herein, a novel water-soluble 5,10,15,20-tetrakis(4-methoxyphenyl-3-sulfonatophenyl) porphyrin (TMPPS) was synthesized with 95% yield by modifying the traditional sulfonation route. The reaction of TMPPS with AgNO3 afforded AgTMPPS an unusual Ag(II) oxidation state (97% yield). The free base and Ag(II) complex were characterized by matrix-assisted laser desorption ionization-mass spectroscopy, and 1H nuclear magnetic resonance, Fourier-transform infrared, UV-vis, fluorescence, and X-ray photolectron spectroscopies. Upon 460 nm laser irradiation, AgTMPPS generated a large amount of 1O2, whereas no ⦁OH was detected. Antibacterial experiments on methicillin-resistant Staphylococcus aureus (MRSA) revealed that the combined action of AgⅡ ions and PDT could endow AgTMPPS with a 100% bactericidal ratio for highly concentrated MRSA (108 CFU/mL) at a very low dosage (4 µM) under laser irradiation at 360 J/cm2. Another PDT response was demonstrated by photocatalytically oxidizing 1,4-dihydronicotinamide adenine dinucleotide to NAD+ with AgTMPPS. The structural features of the TMPPS and AgTMPPS molecules were investigated by density functional theory quantum chemical calculations to demonstrate the efficient chemical and photodynamical effects of AgTMPPS for non-invasive antibacterial therapy.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Porfirinas , Antibacterianos/química , Antibacterianos/farmacologia , NAD/farmacologia , Porfirinas/química , Porfirinas/farmacologia , Prata/química , Prata/farmacologia , Água/farmacologia
3.
ACS Appl Mater Interfaces ; 13(24): 27934-27944, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34101408

RESUMO

Due to conventional photodynamic therapy encountering serious problems of phototoxicity and low tissue-penetrating depth of light, other dynamic therapy-based therapeutic methods such as sonodynamic therapy (SDT) are expected to be developed. To improve the therapeutic response to SDT, more effective sonosensitizers are imperative. In this study, a novel water-soluble iridium(III)-porphyrin sonosensitizer (IrTMPPS) was synthesized and used for SDT. IrTMPPS generated ample singlet oxygen (1O2) under US irradiation and especially showed distinguished US-activatable abilities at more than 10 cm deep-tissue depths. Interestingly, under US irradiation, IrTMPPS sonocatalytically oxidized intracellular NADH, which would enhance SDT efficiency by breaking the redox balance in the tumor. Moreover, IrTMPPS displayed great sonocytotoxicity toward various cancer cells, and in vivo experiments demonstrated efficient tumor inhibition and anti-metastasis to the lungs in the presence of IrTMPPS and US irradiation. This report gives a novel idea of metal-based sonosensitizers for sonotherapy by fully taking advantage of non-invasiveness, water solubility, and deep tumor therapy.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Porfirinas/uso terapêutico , Radiossensibilizantes/uso terapêutico , Animais , Antineoplásicos/síntese química , Antineoplásicos/toxicidade , Linhagem Celular Tumoral , Irídio/química , Irídio/uso terapêutico , Irídio/toxicidade , Camundongos , NAD/química , NAD/metabolismo , Neoplasias/patologia , Oxirredução , Porfirinas/síntese química , Porfirinas/toxicidade , Radiossensibilizantes/síntese química , Radiossensibilizantes/toxicidade , Oxigênio Singlete/metabolismo , Ondas Ultrassônicas , Peixe-Zebra
5.
Chem Commun (Camb) ; (31): 4732-4, 2009 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-19641825

RESUMO

Water-soluble porphyrins can be phase transferred by the hyperbranched multiarm copolymer PEI-PZLys; good catalytic activities and recyclabilities were observed for oxidation catalyzed by the encapsulated porphyrins.


Assuntos
Heme/química , Peptídeos/química , Polímeros/química , Porfirinas/química , Biomimética , Catálise , Estrutura Molecular , Transição de Fase , Solubilidade , Espectrometria de Fluorescência , Água/química
6.
Chemistry ; 10(1): 224-30, 2004 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-14695567

RESUMO

A new chiral binaphthyl-strapped iron-porphyrin 4 b that exhibits unprecedented catalytic activity toward the enantioselective epoxidation of terminal olefins was synthesized. Typical enantiomeric excesses (ee) of 90 % were measured with a maximum of 97 % for the epoxidation of styrene, whereas the turnover numbers (TON) averaged 16000.

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