scholarly journals A Singlet Oxygen Photogeneration and Luminescence Study of Unsymmetrically Substituted Mesoporphyrinic Compounds

2009 ◽  
Vol 2009 ◽  
pp. 1-10 ◽  
Author(s):  
Anabela Sousa Oliveira ◽  
Dumitru Licsandru ◽  
Rica Boscencu ◽  
Radu Socoteanu ◽  
Veronica Nacea ◽  
...  

This paper deals with a series of new unsymmetrically substituted mesoporphyrins: 5-(2-hydroxyphenyl)-10,15,20-tris-phenyl-21,23-H-porphyrin (TPPOHO), 5-(3-hydroxyphenyl)-10,15,20-tris-phenyl-21,23-H-porphyrin (TPPOHM), 5-(4-hydroxyphenyl)-10,15,20-tris-phenyl-21,23-H-porphyrin (TPPOHP), 5-(2-hydroxyphenyl)-10,15,20-tris-butyl-21,23-H-porphyrin (TBPOHO), and their parent nonsubstituted compounds, respectively, 5,10,15,20-tetrakis-phenyl-21,23-H-porphyrin (TPP) and 5,10,15,20-tetrakis-butyl-21,23-H-porphyrin (TBP). Several photophysical studies were carried out to access the influence of the unsymmetrical substitution at the porphyrinic macrocycle on porthyrin's photophysical properties, especially porthyrin's efficiency as singlet oxygen sensitizers. The quantum yields of singlet oxygen generation were determined in benzene (ΦΔ(TPP) = 0.66 ± 0.05;ΦΔ(TPPOHO) = 0.69 ± 0.04;ΦΔ(TPPOHM) = 0.62 ± 0.04;ΦΔ(TPPOHP) = 0.73 ± 0.03;ΦΔ(TBP) = 0.76 ± 0.03;ΦΔ(TBPOHO) = 0.73 ± 0.02) using the 5,10,15,20-tetraphenyl-21,23-H-porphine (ΦΔ(TPP) = 0.66) and Phenazine (ΦΔ(Phz) = 0.83) as reference compounds. Their fluorescence quantum yields were found to be (Φf(TPPOHO) = 0.10 ± 0.04;Φf(TPPOHM) = 0.09 ± 0.03;Φf(TPPOHP) = 0.13 ± 0.02;Φf(TBP) = 0.08 ± 0.03 andΦf(TBPOHO) = 0.08 ± 0.02 using 5,10,15,20-tetraphenyl-21,23-H-porphine as referenceΦf(TPP) = 0.13). Singlet state lifetimes were also determined in the same solvent. All the porphyrins presented very similar fluorescence lifetimes (mean values ofτS(withO2, air equilibrated) = 9.6 ± 0.3 nanoseconds and (withoutO2, argon purged) = 10.1 ± 0.6 nanoseconds, resp.). The phosphorescence emission was found to be negligible for this series of unsymmetrically substituted mesoporphyrins, but an E-type, thermally activated, delayed fluorescence process was proved to occur at room temperature.

2018 ◽  
Vol 22 (01n03) ◽  
pp. 77-87 ◽  
Author(s):  
Mohamad Albakour ◽  
Gülenay Tunç ◽  
Büşra Akyol ◽  
Sinem Tuncel Kostakoğlu ◽  
Savaş Berber ◽  
...  

In this work, Zn(II) phthalocyanine derivative (TTU-Pc) bearing 13-membered tetrathia macrocycles was synthesized, and the novel Zn(II) phthalocyanine derivative was fully characterized by elemental analysis and general spectroscopic methods such as MALDI-TOF mass, FT-IR, UV-vis and [Formula: see text]H-NMR. The synthesized phthalocyanine derivative has quite limited solubility in most of the common organic solvents. Fluorescence measurement was conducted for this Zn(II)phthalocyanine to estimate its fluorescence quantum yields. The singlet oxygen generation ability was also examined to investigate its photosensitizer properties. General trends were described for quantum yields of fluorescence, photodegradation and singlet oxygen quantum yields of this compound. The electrochemical properties of the molecule were investigated by cyclic voltammetry (CV) and square wave voltammetry (SWV). In addition, the lowest energy structure, the electronic structure and frontier molecular orbitals were calculated in DFT and the excitation spectrum was obtained by TDDFT calculations. We found that our computational and experimental results were in agreement.


2020 ◽  
Vol 25 (01) ◽  
pp. 66-74
Author(s):  
Kevser Harmandar ◽  
Esra N. Kaya ◽  
Mehmet F. Saglam ◽  
Ibrahim F. Sengul ◽  
Devrim Atilla

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.


2018 ◽  
Vol 22 (11) ◽  
pp. 1010-1021 ◽  
Author(s):  
Arif Hışır ◽  
Gülşah Gümrükcü Köse ◽  
Göknur Yaşa Atmaca ◽  
Ali Erdoğmuş ◽  
Gülnur Keser Karaoğlan

In order to improve the efficacy of photochemical properties for photodynamic therapy (PDT) applications, carboxylic acid groups axially conjugated with silicon(IV) and at the peripheral position with zinc(II) phthalocyanine skeletons for new photosensitizers to investigate the influence of the COOH group positions on the photophysicochemical performance are described in this study. Silicon (IV) (3 and 5) and zinc (II) (7) phthalocyanines were characterized by UV-vis, FTIR, 1H-NMR, MALDI-TOF MS and elemental analysis spectral data. Furthermore, the photophysical (fluorescence quantum yields and fluorescence quenching studies), photochemical (photodegradation and singlet oxygen generation) and aggregation properties of the newly synthesized phthalocyanines were investigated in dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) solutions. The results were compared with that of zinc and silicon phthalocyanines. Singlet oxygen quantum yields ranged from 0.23 to 0.63 via Type II mechanism under the experimental conditions studied. The fluorescence of the phthalocyanine complexes (3, 5 and 7) is effectively quenched by 1,4-benzoquinone (BQ) in DMSO, DMF and THF.


2003 ◽  
Vol 07 (06) ◽  
pp. 439-446 ◽  
Author(s):  
Prudence Tau ◽  
Abimbola O. Ogunsipe ◽  
Suzanne Maree ◽  
M. David Maree ◽  
Tebello Nyokong

The effects of formation of cyclodextrin inclusion complexes on the photochemical and photophysical properties of zinc phthalocyanine ( ZnPc ) and various peripherally substituted zinc phthalocyanines as well as zinc naphthalocyanine ( ZnNPc ) are investigated. The cyclodextrins employed were the hydroxypropyl-γ-cyclodextrin and unsubstituted β-cyclodextrin. Job's plots were employed to confirm the stoichiometry of the inclusion complexes and showed 2:1 and 4:1 (cyclodextrin:phthalocyanine) inclusion behavior. The phthalocyanine inclusion complexes showed larger singlet oxygen quantum yield (ϕΔ) values when compared to the free phthalocyanines before inclusion, for complexes 1 (zinc naphthalocyanine), 2 (zinc tetranitrophthalocyanine) and 4 (zinc tetra-tert-butylphenoxyphthalocyanine). The fluorescence quantum yields generally remained unchanged following inclusion.


2019 ◽  
Vol 126 (2) ◽  
pp. 162
Author(s):  
И.В. Багров ◽  
А.В. Дадеко ◽  
В.М. Киселев ◽  
Т.Д. Муравьева ◽  
А.М. Стародубцев

AbstractThe photophysical properties of three photosensitizers—dimegine, photoditazine, and radachlorin—have been comparatively examined. For dimegine and photoditazine, two techniques have been used to measure the singlet oxygen generation quantum yields and the quenching constants of singlet oxygen by dimegine and photoditazine, as well as the dimegine fluorescence quantum yield.


2018 ◽  
Vol 22 (09n10) ◽  
pp. 847-852 ◽  
Author(s):  
Xian-Fu Zhang ◽  
Xiaojie Sun

The synthesis, fluorescence properties and singlet oxygen generation capability of germanium tetrabenzotriazacorrole (LGeTBC), germanium phthalocyanine (Cl[Formula: see text]GePc) and their derivatives are described. Measurements include UV-vis absorption spectra, fluorescence emission spectra, fluorescence quantum yields fluorescence lifetimes, and singlet delta oxygen quantum yields. LGeTBC and its derivatives exhibit quite different spectral and fluorescence properties from their phthalocyanine precursor. Both LGeTBC and Cl[Formula: see text]GePc show high singlet delta oxygen quantum yields and suitable fluorescence quantum yields, indicating that they can act as good singlet oxygen photosensitizers for photodynamic therapy.


2018 ◽  
Vol 22 (01n03) ◽  
pp. 266-278 ◽  
Author(s):  
Halid Kuruca ◽  
Baybars Köksoy ◽  
Begümhan Karapınar ◽  
Mahmut Durmuş ◽  
Mustafa Bulut

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.


2015 ◽  
Vol 19 (10) ◽  
pp. 1114-1122 ◽  
Author(s):  
Esra Nur Kaya ◽  
Mahmut Durmuş ◽  
Mustafa Bulut

The novel zinc(II) phthalocyanine complexes bearing tetra or octa-[7-oxy-3-(3′,4′,5′-trimethoxyphenyl)coumarin] moieties were synthesized for the first time in this study. These phthalocyanines were characterized by different spectroscopic methods such as FT-IR, 1H NMR, electronic absorption spectra, MALDI-TOF mass and elemental analyses as well. The photochemical properties such as singlet oxygen generation, photostability and photophysical properties such as fluorescence quantum yields and lifetimes were investigated in [Formula: see text],[Formula: see text]-dimethylformamide (DMF) solutions. The effect of the structure (the position and number of the coumarin groups on phthalocyanine framework) of novel phthalocyanines on these properties was also determined in this study.


Molecules ◽  
2019 ◽  
Vol 24 (5) ◽  
pp. 863 ◽  
Author(s):  
Filipa Mandim ◽  
Vânia C. Graça ◽  
Ricardo C. Calhelha ◽  
Isabel L. F. Machado ◽  
Luis F. V. Ferreira ◽  
...  

In this work, several benzothiazole-based aminosquaraine dyes, displaying strong absorption within the so-called phototherapeutic window (650–800 nm), were synthesized. The ability, of all the new dyes, to generate singlet oxygen was assessed by determining the correspondent phosphorescence emission and through the comparison with a standard. The quantum yields of singlet oxygen generation were determined and exhibited to be strongly dependent on the nature of the amino substituents introduced in the squaric ring. The photodynamic activity of the synthesized dyes was tested against four human tumor cell lines: breast (MCF-7), lung (NCI-H460), cervical (HeLa) and hepatocellular (HepG2) carcinomas; and a non-tumor porcine liver primary cell culture (PLP2). All the compounds synthesized were found to be able to inhibit tumor cells growth upon irradiation more than in the dark, in most of the cases, very significantly. Considering the photodynamic activity exhibited and the low toxicity displayed for the non-tumor cells, some of the synthetized dyes can be regarded as potential candidates as photosensitizers for PDT.


2021 ◽  
Vol 903 ◽  
pp. 155-161
Author(s):  
Armands Sebris ◽  
Kaspars Traskovskis ◽  
Irina Novosjolova ◽  
Māris Turks

Electron donating phenoxazine and phenothiazine groups were introduced in an electron deficient purine structure through a benzene ring bridge to facilitate thermally activated delayed fluorescence. Mitsunobu and Suzuki-Miyaura reactions were used to synthesize the target compounds. Photophysical properties of target compounds were explored and quantum yields in the thin layer film reached up to 8 % and in the PMMA doped thin layer film up to 15 %.


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