Alkaloids as Photosensitisers for the Inactivation of Bacteria

Antimicrobial photodynamic therapy has emerged as a powerful approach to tackle microbial infections. Photodynamic therapy utilises a photosensitiser, light, and oxygen to generate singlet oxygen and/or reactive oxygen species in an irradiated tissue spot, which subsequently react with nearby biomolecules and destroy the cellular environment. Due to the possibility to irradiate in a very precise location, it can be used to eradicate bacteria, fungus, and parasites upon light activation of the photosensitiser. In this regard, natural products are low-cost molecules capable of being obtained in large quantities, and some of them can be used as photosensitisers. Alkaloids are the largest family among natural products and include molecules with a basic nature and aromatic rings. For this study, we collected the naturally occurring alkaloids used to treat microorganism infections using a photodynamic inactivation approach. We gathered their main photophysical properties (excitation/emission wavelengths, quantum yields, and oxygen quantum yield) which characterise the ability to efficiently photosensitise. In addition, we described the antibacterial activity of alkaloids upon irradiation and the mechanisms involved in the microorganism killing. This review will serve as a reference source to obtain the main information on alkaloids used in antimicrobial photodynamic therapy.

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New peripherally substituted lutetium mono and bis phthalocyanines: Synthesis and comparative photophysical and photochemical properties

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424619501840 ◽

2019 ◽

Vol 23 (11n12) ◽

pp. 1542-1550

Author(s):

Nagihan Kocaağa ◽

Öznur Dülger Kutlu ◽

Ali Erdoğmuş

Keyword(s):

Mass Spectrometry ◽

Photodynamic Therapy ◽

Singlet Oxygen ◽

Photophysical Properties ◽

Quantum Yields ◽

Synthesis And Characterization ◽

Type Ii ◽

H Nmr ◽

Photochemical Properties

In this study, the synthesis and characterization of mono-(phthalocyaninato) lutetium(III) (1-Cl and 1-F) [Lu[Formula: see text](AcO)(Pc)] (Pc [Formula: see text] phthalocyaninato, AcO [Formula: see text] acetate) and bis-(phthalocyaninato) lutetium(III) (2-Cl and 2-Br) [Lu[Formula: see text]Pc[Formula: see text]] bearing halogenated (F, Cl and Br) phenoxy–phenoxy groups are described and verified by IR, [Formula: see text]H-NMR, UV-vis and mass spectrometry. Photochemical and photophysical properties of 1-F, 1-Cl 2-Cl and 2-Br in DMSO are also presented. A comparison between photophysical and photochemical parameters of mono and bis derivatives showed that mono phthalocyanines are better photosensitizers than bis phthalocyanines. Photophysical and photochemical properties of phthalocyanines are very useful for photodynamic therapy applications. Singlet oxygen quantum yields [Formula: see text] give an indication of the potential of the complexes as photosensitizers in photodynamic therapy applications. The chloro, fluoro, bromo-phenoxy–phenoxy substituted mono-(phthalocyaninato) lutetium(III) complexes (1-Cl and 1-F) gave good singlet oxygen quantum yields (from 0.86 to 0.80) in DMSO. Thus, these complexes show potential as Type II photosensitizers for PDT of cancer.

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Thioalkyl- and Sulfone-Substituted Poly(p-Phenylene Vinylene)s

10.26434/chemrxiv.7265174 ◽

2018 ◽

Author(s):

Martina Rimmele ◽

Klaus Ableidinger ◽

Adam V. Marsh ◽

Nathan J. Cheetham ◽

M. Josef Taublaender ◽

...

Keyword(s):

Molecular Weight ◽

High Molecular Weight ◽

Low Cost ◽

Photophysical Properties ◽

Quantum Yields ◽

Phenylene Vinylene ◽

Structural Variations ◽

Interesting Class ◽

New Applications ◽

Exceptional Stability

Poly(p-phenylene vinylene)s (PPVs) have been studied for decades, but research on this interesting class of conjugated polymers is far from being completed. New applications like in bioimaging keep emerging and even simple structural variations are still waiting to be explored. Surprisingly, not even dithioalkyl-substituted PPVs (S-PPVs) have been reported in the peer-reviewed literature, although the corresponding dialkoxy-substituted PPVs (O-PPVs) like MEH-PPV or MDMO-PPV are most frequently used and although thioalkyl substituents can improve the material properties significantly. We herein report the development of a highly efficient, scalable two-step synthesis of Gilch monomers for S-PPVs starting from low-cost 1,4-diiodobenzene. A low-temperature polymerization protocol has been developed for these monomers, affording high-molecular weight S-PPVs in excellent yields. The thermal, electrochemical, and photophysical properties of S-PPVs are reported to highlight the potential of these polymers. Furthermore, treatment with dimethyldioxirane is demonstrated to result in rapid conversion into sulfone-substituted PPVs (SO<sub>2</sub>-PPVs), introducing a route to high-molecular weight SO<sub>2</sub>-PPVs with exceptional stability and solid-state photoluminescence quantum yields of up to 0.46.

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Mitochondria-targeted porphyrin-based photosensitizers containing triphenylphosphonium cations showing efficient in vitro photodynamic therapy effects

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424619501682 ◽

2019 ◽

Vol 23 (11n12) ◽

pp. 1505-1514 ◽

Cited By ~ 1

Author(s):

Xing Guo ◽

Hao Wu ◽

Wei Miao ◽

Yangchun Wu ◽

Erhong Hao ◽

...

Keyword(s):

Photodynamic Therapy ◽

Cancer Therapy ◽

Fluorescence Spectroscopy ◽

Hela Cells ◽

Photophysical Properties ◽

Quantum Yields ◽

Subcellular Organelle

Subcellular organelle-targeted photosensitizers have recently reported to be effective photodynamic therapy (PDT) agents. In this work, three porphyrin-derived photosensitizers, containing one, two or four triphenylphosphonium targeting groups, were synthesized and characterized by NMR, HRMS, UV-vis and fluorescence spectroscopy. These photosensitizers showed similar photophysical properties to classical porphyrins and exhibited excellent [Formula: see text]O[Formula: see text] quantum yields in acetonitrile. Subcellular colocalization indicated that all three photosensitizers specifically stain the mitochondria of HeLa cells. Photosensitizer mito-dp, containing two triphenylphosphonium cations was found to be the most uptaken by cells and exhibited the best PDT effect with an effective phototoxicity (IC[Formula: see text] (light) [Formula: see text] 12.4 nM), suggestive of a higher practicable potential of mitochondria-targeted PDT agents in cancer therapy.

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Metallophthalocyanines for antimicrobial photodynamic therapy: an overview of our experience

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424613300024 ◽

2013 ◽

Vol 17 (06n07) ◽

pp. 399-416 ◽

Cited By ~ 28

Author(s):

Vanya N. Mantareva ◽

Ivan Angelov ◽

Dieter Wöhrle ◽

Ekaterina Borisova ◽

Vesselin Kussovski

Keyword(s):

Photodynamic Therapy ◽

Metal Ion ◽

Soret Band ◽

Quantum Yields ◽

Anionic Complex ◽

Antimicrobial Photodynamic Therapy ◽

Metal Phthalocyanine ◽

Metal Phthalocyanines ◽

The Media ◽

Positively Charged

Metal phthalocyanine complexes with different charges, hydrophobicity and metal ions were synthesized and studied for antimicrobial photodynamic therapy of pathogenic bacterial and fungal model strains. Ten positively charged complexes with the metals Zn ( II ), Al ( III ), Ga ( III ), In ( III ), Si ( IV ) and Ge ( IV ) in the center of the ligand and substituents at the ligand bearing four or eight N-alkylpyridyloxy groups were prepared. In addition, a negatively charged Zn ( II )-phthalocyanine with four sulfophenoxy-groups was synthesized. The absorption spectra showed low intensity of the Soret band in the UV part of the spectrum and the intense Q-band in the red to far red region (λ = 671–697 nm). The fluorescence was determined with quantum yields between 0.1–0.33 and life-times 2.8–4.9 ns in dependence of the kind of metal ion and the substituents. In organic solvents all complexes exist in a monomeric state but in aqueous solution they show aggregation with the exception of Ga ( III ) phthalocyanines. The singlet oxygen quantum yields were evaluated in dependence on the metals, substituents and the media with values between 0.16–0.68. The cationic metal phthalocyanines were taken-up by pathogenic cells in a higher amount as compared to the anionic complex. Three of the studied phthalocyanines namely tetra-N-methylpyridyloxy-phthalocyanine Zn ( II ) and tetra- and octa-N-methylpyridyloxy- Ga ( III ) phthalocyanines showed a high photodynamic efficacy towards most of the studied microorganisms in suspensions.

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Photophysical properties of Zn(II) phthalocyaninates incorporated into liposomes

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424602000166 ◽

2002 ◽

Vol 06 (02) ◽

pp. 122-129 ◽

Cited By ~ 22

Author(s):

Myriam E. Rodriguez ◽

Josefina Awruch ◽

Lelia Dicelio

Keyword(s):

Photodynamic Therapy ◽

Solid Tumor ◽

Water Solubility ◽

Photophysical Properties ◽

Association Constants ◽

The Other ◽

Quantum Yields ◽

Tumor Models ◽

Fluorescence Quantum Yields ◽

Cellular Components

Amphiphilic phthalocyanines are used as potential photosensitizers in photodynamic therapy. The low water solubility of most of these dyes is the reason that different kinds of vehicles are employed as endogenous carriers. Due to the photophysical inactivity of the phthalocyanine aggregates, it is important to improve their solubility in order to study dyes in solid tumor models. On the other hand, the photodynamic therapy activity depends on the location of phthalocyanines in the cell and the interaction of cellular components. In this work, the photophysical properties of tetrasubstituted Zn ( II ) phthalocyanines with different lipophilic properties are incorporated into liposomes of L-α-dimyristoylphosphatidylcholine (DMPC). The fluorescence quantum yields, the association constants and their localization in the membranes are reported.

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Photophysical Properties of Pheophorbide-a Derivatives and Their Photodynamic Therapeutic Effects on a Tumor Cell LineIn Vitro

International Journal of Photoenergy ◽

10.1155/2014/793723 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 2

Author(s):

Kang-Kyun Wang ◽

Jing Li ◽

Bong-Jin Kim ◽

Jeong-Hyun Lee ◽

Hee-Won Shin ◽

...

Keyword(s):

Photodynamic Therapy ◽

Triplet State ◽

Singlet Oxygen ◽

Alkyl Group ◽

Photophysical Properties ◽

Hydroxyl Group ◽

Quantum Yields ◽

Therapeutic Effects ◽

Pheophorbide A

Pheophorbide-a derivatives have been reported to be potential photosensitizers for photodynamic therapy (PDT). In this study, photophysics of pheophorbide-a derivatives (PaDs) were investigated along with their photodynamic tumoricidal effectin vitro. PaDs were modified by changing the coil length and/or making the hydroxyl group (–OH) substitutions. Their photophysical properties were studied by steady-state and time-resolved spectroscopic methods. The photodynamic tumoricidal effect was evaluated in the mouse breast cancer cell line (EMT6). Lifetime and quantum yield of fluorescence and quantum yields of triplet state and singlet oxygen were studied to determine the dynamic energy flow. The coil length of the substituted alkyl group did not significantly affect the spectroscopic properties. However, the substitution with the hydroxyl group increased the quantum yields of the triplet state and the singlet oxygen due to the enhanced intersystem crossing. In order to check the application possibility as a photodynamic therapy agent, the PaDs with hydroxyl group were studied for the cellular affinity and the photodynamic tumoricidal effect of EMT6. The results showed that the cellular affinity and the photodynamic tumoricidal effect of PaDs with the hydroxyl group depended on the coil-length of the substituted alkyl group.

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Photophysical and photochemical properties of newly synthesized zinc(II) and chloroindium(III) phthalocyanines substituted with 3,5-bis (trifluoromethyl)phenoxy groups

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s108842461950055x ◽

2019 ◽

Vol 23 (07n08) ◽

pp. 960-968 ◽

Cited By ~ 9

Author(s):

Erem Ahmetali ◽

Göknur Yaşa Atmaca ◽

Hande Pekbelgin Karaoğlu ◽

Ali Erdoğmuş ◽

Makbule Burkut Koçak

Keyword(s):

Photodynamic Therapy ◽

Photophysical Properties ◽

Quantum Yields ◽

Fluorescence Quantum Yields ◽

Zinc Phthalocyanines ◽

Photochemical Properties ◽

Photocatalytic Applications

4,5-bis(3,5-bis(trifluoromethyl)phenoxy)phthalonitrile (1) and its complexes, namely 2,3,9,10,16,17,23,24-octakis[3,5-bis(trifluoromethyl)phenoxy] phthalocyaninato zinc(II) (2) and 2,3,9,-10,16,17,23,24-octakis[3,5-bis(trifluoromethyl)phenoxy]phthalocyaninato indium(III) (3) are synthesized and characterized. Aggregation of the phthalocyanines was studied in tetrahydrofuran in different concentrations. Photochemical and photophysical properties of 2 and 3 in THF were investigated. A comparison between the photophysicochemical parameters of 2 and 3 yielded that 3 is a better photosensitizer than 2. The fluorescence quantum yields (ΦF) and 1O2 formation ([Formula: see text] for compound 3 are 0.016 and 0.84, respectively. The values for compound 2 are 0.135 and 0.54, respectively. The values of indium and zinc phthalocyanines (2 and 3) could be classified as photosensitizers in the photocatalytic applications such as photodynamic therapy (PDT) of cancer.

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Synthesis of pH-Responsive Glycopolymer with End Group Zinc(II) Phthalocyanines as Potential Photosensitizer

Materials Science Forum ◽

10.4028/www.scientific.net/msf.996.82 ◽

2020 ◽

Vol 996 ◽

pp. 82-87

Author(s):

Shu Guo Dong ◽

Gui Hua Cui ◽

Qian Duan

Keyword(s):

Photodynamic Therapy ◽

Singlet Oxygen ◽

Raft Polymerization ◽

Photophysical Properties ◽

Water Soluble ◽

Quantum Yields ◽

Oxygen Species ◽

Ph Responsive ◽

Reversible Addition ◽

Singlet Oxygen Species

A novel end-functionalized glycopolymer poly (3-O-methacryloyl-D-glucofuranose) -b-poly (2-Diethylaminoethyl Methacrylate) (PMAGlc-b-PDEA-ZnTAPc) with zinc (II) teraamaninophthalocyanine was synthesized. First, a pH-responsive copolymer PMAIpG-b-PDEA was synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization. Then PMAIpG-b-PDEA reacted with ZnTAPc and deprotected to form a water-soluble and pH-responsive photosensitizer. The structure of the PMAGlc-b-PDEA-ZnTAPc was characterized by 1H NMR and GPC. The photophysical properties were evaluated by UV-Vis and fluorescence spectra. The PMAGlc-b-PDEA-ZnTAPc can generate singlet oxygen species with good singlet oxygen quantum yields (Φ△=0.38), which is believed to be the major cytotoxic reactive oxygen species (ROS) for photodynamic therapy. The ZnPc functionalized glycopolymer will be used as a potential photosensitizer in the fields of photodynamic therapy.

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Synthesis and photophysicochemical properties of BODIPY dye functionalized gold nanorods for use in antimicrobial photodynamic therapy

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s108842461650070x ◽

2016 ◽

Vol 20 (08n11) ◽

pp. 1016-1024 ◽

Cited By ~ 12

Author(s):

Gugu Kubheka ◽

Imran Uddin ◽

Edith Amuhaya ◽

John Mack ◽

Tebello Nyokong

Keyword(s):

Gold Nanoparticles ◽

Photodynamic Therapy ◽

Singlet Oxygen ◽

Gold Nanorods ◽

Molecular Modelling ◽

Quantum Yields ◽

Antimicrobial Photodynamic Therapy ◽

Boron Dipyrromethene

A series of boron dipyrromethene (BODIPY) dyes with properties that are ideal for a good photosensitizer have been prepared. Functionalization with bromine atoms and attachment to gold nanoparticles through a meso-aniline group results in high singlet oxygen quantum yields and low fluorescent quantum yields. Molecular modelling was used to analyze trends in the MO energies of various brominated aniline BODIPY dyes.

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