scholarly journals Meso-substituted cationic 3- and 4-N-Pyridylporphyrins and their Zn(II) derivatives for antibacterial photodynamic therapy

2021 ◽  
Author(s):  
Aram G. Gyulkhandanyan ◽  
Marina H. Paronyan ◽  
Anna G. Gyulkhandanyan ◽  
Karapet R. Ghazaryan ◽  
Marina V. Parkhats ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Singlet Oxygen ◽  
Aureus Strain ◽  
Quantum Yields ◽  
Central Metal Atom ◽  
Central Metal ◽  
Cationic Porphyrins ◽  
Oxygen Generation ◽  
High Antibacterial Activity ◽  
High Degree

Photodynamic inactivation of microorganisms known as antibacterial photodynamic therapy (APDT) is one of the most promising and innovative approaches for the destruction of pathogenic microorganisms. Among the photosensitizers (PSs), compounds based on cationic porphyrins/metalloporphyrins are most successfully used to inactivate microorganisms. Series of meso-substituted cationic pyridylporphyrins and metalloporphyrins with various peripheral groups in the third and fourth positions of the pyrrole ring have been synthesized in Armenia. The aim of this work was to determine and test the most effective cationic porphyrins and metalloporphyrins with high photoactivity against Gram negative and Gram positive microorganisms. It was shown that the synthesized cationic pyridylporphyrins/metalloporphyrins exhibit a high degree of phototoxicity towards both types of bacteria, including the methicillin-resistant S. aureus strain. Zinc complexes of porphyrins are more phototoxic than metal-free porphyrin analogs. The effectiveness of these Zn–metalloporphyrins on bacteria is consistent with the level of singlet oxygen generation. It was found that the high antibacterial activity of the studied cationic porphyrins/metalloporphyrins depends on four factors: the presence in the porphyrin macrocycle of a positive charge (+4), a central metal atom (Zn[Formula: see text] and hydrophobic peripheral functional groups as well as high values of quantum yields of singlet oxygen. The results indicate that meso-substituted cationic pyridylporphyrins/metalloporphyrins can find wider application in photoinactivation of bacteria than anionic or neutral PSs usually used in APDT.

Zinc(II) and chloroindium(III) phthalocyanines bearing ethyl 7-oxy-6-chloro-4-methylcoumarin-3-propanoate groups: Synthesis, characterization and investigation of their photophysicochemical properties

2018 ◽  
Vol 22 (01n03) ◽  
pp. 266-278 ◽  
Author(s):  
Halid Kuruca ◽  
Baybars Köksoy ◽  
Begümhan Karapınar ◽  
Mahmut Durmuş ◽  
Mustafa Bulut
Keyword(s):  
Singlet Oxygen ◽  
Quantum Yields ◽  
Central Metal Atom ◽  
Central Metal ◽  
Chloride Complexes ◽  
Oxygen Generation ◽  
Fluorescence Quantum Yields ◽  
H Nmr ◽  
Ft Ir

In this study, ethyl 7-hydroxy-6-chloro-4-methylcoumarin-3-propanoate (1), ethyl 7-(2,3-dicyanophenoxy)-6-chloro-4-methylcoumarin-3-propanoate (2), ethyl 7-(3,4-dicyanophenoxy)-6-chloro-4-methylcoumarin-3-propanoate (3), ethyl 4-chloro-5-(7-oxy-6-chloro-4-methylcoumarin-3-propanoate)phthalonitrile (4) were synthesized. The phthalonitrile derivatives (2, 3 and 4) were converted to their peripheral tetra, non-peripheral tetra and peripheral chlorocta substituted zinc(II) and chloroindium phthalocyanine derivatives. All novel compounds were characterized by elemental analysis, FT-IR, [Formula: see text]H-NMR, MALDI-TOF mass spectrometry and UV-vis spectral data. Additionally, the spectral, photophysical (fluorescence quantum yields and lifetimes) and photochemical (singlet oxygen generation and photodegradation under light irradiation) properties of the resulting substituted phthalocyaninatozinc(II) and indium(III) chloride complexes (5–10) were investigated in DMF, and the obtained results were compared for determination of the effects of the substituents’ positions and the variety of the central metal atom on these properties. The fluorescence quenching behavior of these phthalocyanines (5–10) were also investigated using 1,4-benzoquinone as a quencher. The obtained ethyl 7-oxy-6-chloro-4-methylcoumarin-3-propanoate bearing phthalocyaninatozinc(II) (5, 7 and 9) and indium(III) chloride (6, 8 and 10) complexes showed excellent solubility in most organic solvents. They produced high singlet-oxygen and showed appropriate photodegradation which is very important for photodynamic therapy applications.

Bis-indole substituted phthalocyanines: Photophysical and photochemical properties

2020 ◽  
Vol 25 (01) ◽  
pp. 66-74
Author(s):  
Kevser Harmandar ◽  
Esra N. Kaya ◽  
Mehmet F. Saglam ◽  
Ibrahim F. Sengul ◽  
Devrim Atilla
Keyword(s):  
Photodynamic Therapy ◽  
Singlet Oxygen ◽  
Spectral Data ◽  
Quantum Yields ◽  
Oxygen Generation ◽  
Fluorescence Quantum Yields ◽  
H Nmr ◽  
Singlet Oxygen Generation ◽  
Photochemical Properties ◽  
C Nmr

Tetra substituted peripheral and non-peripheral Zn(II) phthalocyanines were successfully synthesized employing 4-(bis(3-methyl-1H-indol-2-yl)methyl)phenol as a starting material. The structure of these synthesized compounds was confirmed using 1H NMR, [Formula: see text]C NMR, infrared (IR), UV-vis, and MALDI-TOF spectral data. The photophysical (fluorescence quantum yields and lifetimes) and photochemical (singlet oxygen generation) properties of all synthesized peripheral and non-peripheral compounds were investigated in order to determine the potential of these compounds for application in photodynamic therapy.

Photophysical and photochemical properties of fluoroether-substituted zinc(II) and titanium(IV) phthalocyanines

2018 ◽  
Vol 22 (01n03) ◽  
pp. 46-55 ◽  
Author(s):  
İlke Gürol ◽  
Gülay Gümüş ◽  
Deniz Kutlu Tarakci ◽  
Ömer Güngör ◽  
Mahmut Durmuş ◽  
...  
Keyword(s):  
Quantum Yields ◽  
Central Metal Atom ◽  
Spectroscopic Techniques ◽  
Central Metal ◽  
Oxygen Generation ◽  
Fluorescence Quantum Yields ◽  
H Nmr ◽  
Photochemical Properties ◽  
First Time

The synthesis and characterization of novel zinc(II) (1a–4a) and oxo-titanium(IV) (1b–4b) phthalocyanine derivatives bearing 1H,1H-nona?uoro-3,6-dioxaheptan-1-ol groups are described for the first time. These phthalocyanines (1a–4a and 1b–4b) were characterized by elemental analysis and different spectroscopic techniques such as UV-vis, [Formula: see text]H NMR, FTIR and mass. Furthermore, the photophysical (fluorescence quantum yields and lifetimes) and photochemical (singlet oxygen generation and photodegradation) properties of these phthalocyanines were investigated in tetrahydrofuran (THF) solution. The influence of the number of the substituted groups (tetra or octa), position of the substituents (peripheral or non-peripheral) and central metal atom (zinc or titanium) on the photophysical and photochemical properties of these phthalocyanines were evaluated.

Desired properties of new phthalocyanines for photodynamic therapy

2011 ◽  
Vol 83 (9) ◽  
pp. 1763-1779 ◽  
Author(s):  
Tebello Nyokong
Keyword(s):  
Photodynamic Therapy ◽  
Singlet Oxygen ◽  
Fluorescence Quantum Yield ◽  
Resonance Energy Transfer ◽  
Resonance Energy ◽  
Ring Expansion ◽  
Quantum Yields ◽  
Electromagnetic Spectrum ◽  
Central Metal ◽  
Triplet Quantum Yields

The manuscript focuses on the properties of phthalocyanines (Pcs) that are required for them to be employed as photosensitizers in applications such as photodynamic therapy (PDT). High triplet-state quantum yields and lifetimes as well as high singlet-oxygen quantum yields are required for a good photosensitizer. In addition, absorption of the photosensitizer in the red region of the electromagnetic spectrum is also required, and this can be achieved by ring expansion, substitution with electron-donating ligands, and change of the central metal among others. Quantum dots (QDs) are efficient accumulators of light energy, and they can transfer this energy to molecules that possess a very efficient ability to generate singlet oxygen through a process called Förster resonance energy transfer (FRET). Thus, there is a decrease in the fluorescence quantum yield of the QDs when in the vicinity of Pcs. Triplet quantum yields of the Pcs increase in the presence of QDs.

The construction of phthalocyanine- carbon nanoparticle conjugates for applications in photodynamic therapy and non-linear optics

2021 ◽  
Author(s):  
◽  
Refilwe Matshitse
Keyword(s):  
Photodynamic Therapy ◽  
Quantum Yield ◽  
Cell Viability ◽  
Singlet Oxygen ◽  
Direct Relationship ◽  
Amide Bond ◽  
Detonation Nanodiamonds ◽  
Quantum Yields ◽  
Central Metal ◽  
Carbon Based

The syntheses and characterization of symmetric and asymmetric Pcs functionalized at the peripheral position and sometimes positively charged are reported. The Pcs had either H2, zinc or silicon as central metals and have pyridyloxy, benzothiozole phenoxy, and respective cationic analogues as ring substituents. The Pcs were linked to carbon based nanoparticles such as graphene quantum dots, carbon dots, and detonation nanodiamonds (DNDs) via an ester, amide bond and/or π - π stacking. The physicochemical characteristics of the Pcs were assessed when alone and when in a conjugated system. Both symmetrically and asymmetrically substituted benzothiozole Pcs when quaternised displayed higher triplet and singlet oxygen quantum yields than their unquaternised counterparts. Linkage to carbon nanoparticles (especially to detonation nanodiamonds) had an increasing effect on triplet and singlet oxygen quantum yield. However, a general decrease in singlet oxygen quantum yield on linkage to doped detonation nanodiamonds was associated with the screening effect of DNDs. Heteroatom doped DNDs-Pc nanohybrids have less singlet oxygen than Pcs alone due to molecular structural stability associated with strain that is relatively reduced upon linking Pcs. The In vitro dark cytotoxicity and photodynamic therapy of selected Pc complexes and conjugates against MCF-7 cells was tested. All studied Pc complexes and conjugates showed minimum dark toxicity making them applicable for PDT. When Pc complexes are alone, there is less phototoxicity with >22% cell viability at concentrations ≤ 50 μg/mL relative to conjugates with <22% cell viability at concentrations ≤ 50 μg/mL. There was no direct relationship between PDT and singlet oxygen quantum yields. Nonlinear optical characteristics of complexes was improved upon conjugation of DNDs. Absorbance, input energy, percentage loading, central metal, substituent of Pc and nature of interaction (covalent, noncovalent) are amongst some of the factors that influence nonlinear absorption properties of materials used in this study. All materials followed reverse saturable absorption through two photon absorption mechanism at the excitation wavelength of 532 nm. Aggregates reduce excited state lifetime and Beff under high concentrations/absorbance. A direct relationship between absorbance and Beff of DNDs nanoconjugated systems at low concentrations result in increased optical limiting characteristics of materials. The findings from this work show the importance of linking (nonlinear optics and photodynamic therapy) and doping (photodynamic therapy) photosensitisers such as phthalocyanines and sometimes boron dipyrromethenes onto carbon based nanoparticles for the enhanced characteristics in variable applications.

Design of Novel Photosensitizers and Controlled Singlet Oxygen Generation for Photodynamic Therapy

2021 ◽  
Author(s):  
Esra Tanrıverdi Eçik ◽  
Onur BULUT ◽  
Hasan Hüseyin Kazan ◽  
Elif Şenkuytu ◽  
Bunyemin Cosut
Keyword(s):  
Photodynamic Therapy ◽  
Cancer Treatment ◽  
Singlet Oxygen ◽  
Side Effect ◽  
Side Effect Profile ◽  
High Ability ◽  
Lower Side ◽  
Oxygen Generation ◽  
Singlet Oxygen Generation ◽  
Promising Strategy

Photodynamic therapy (PDT) is a promising strategy in cancer treatment with its relatively lower side effect profile. Undoubtedly, the key component of PDT is the photosensitizers with a high ability...

Biodegradable Nano-photosensitizer with Photoactivatable Singlet Oxygen Generation for Synergistic Phototherapy

2021 ◽  
Author(s):  
Jiaxin Shen ◽  
Dandan Chen ◽  
Ye Liu ◽  
Guoyang Gao ◽  
Zhihe Liu ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Cancer Therapy ◽  
Singlet Oxygen ◽  
Near Infrared ◽  
Promising Method ◽  
Normal Cells ◽  
Oxygen Generation ◽  
Singlet Oxygen Generation ◽  
Nir Light

Photodynamic therapy (PDT) is a promising method for cancer therapy and also may initiate unexpected damages to normal cells and tissues. Herein, we developed a near-infrared (NIR) light-activatable nanophotosensitizer, which...

scholarly journals Correction: Efficient singlet oxygen generation from sugar pendant C60 derivatives for photodynamic therapy

2015 ◽  
Vol 51 (99) ◽  
pp. 17631-17632 ◽  
Author(s):  
Shigenobu Yano ◽  
Masami Naemura ◽  
Akio Toshimitsu ◽  
Motofusa Akiyama ◽  
Atsushi Ikeda ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Singlet Oxygen ◽  
Oxygen Generation ◽  
Singlet Oxygen Generation ◽  
C60 Derivatives

Correction for ‘Efficient singlet oxygen generation from sugar pendant C60 derivatives for photodynamic therapy’ by Shigenobu Yano et al., Chem. Commun., 2015, DOI: 10.1039/c5cc07353g.

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