scholarly journals Photophysicochemical Properties and In Vitro Phototherapeutic Effects of Iodoquinoline- and Benzothiazole-Derived Unsymmetrical Squaraine Cyanine Dyes

2019 ◽  
Vol 9 (24) ◽  
pp. 5414 ◽  
Author(s):  
Sofia Friães ◽  
Eurico Lima ◽  
Renato E. Boto ◽  
Diana Ferreira ◽  
José R. Fernandes ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Singlet Oxygen ◽  
Cell Lines ◽  
Light Emitting Diode ◽  
Cyanine Dyes ◽  
Quantum Yields ◽  
Light Emitting ◽  
Diode System ◽  
Hepg2 Cell Lines

The search to replace conventional cancer treatment therapies, such as chemotherapy, radiotherapy and surgery has led over the last ten years, to a substantial effort in the development of several classes of photodynamic therapy photosensitizers with desired photophysicochemical and photobiological properties. Herein we report the synthesis of 6-iodoquinoline- and benzothiazole-based unsymmetrical squaraine cyanine dyes functionalized with amine groups located in the four-membered central ring. Their photodegradation and singlet oxygen production ability, as well as their in vitro photocytotoxicity against Caco-2 and HepG2 cell lines using a 630.8 ± 0.8 nm centered light-emitting diode system, were also investigated. All photosensitizer candidates displayed strong absorption within the tissue transparency spectral region (650–850 nm). The synthesized dyes were found to have moderate light stability. The potential of these compounds is evidenced by their cytotoxic activity against both tumor cell lines, highlighting the zwitterionic unsubstituted dye, which showed more intense photodynamic activity. Although the singlet oxygen quantum yields of these iodinated derivatives are considered low, it could be concluded that their introduction into the quinoline heterocycle was highly advantageous as it played a role in increasing selective cytotoxicity in the presence of light. Thus, the novel synthesized dyes present photophysicochemical and in vitro photobiological properties that make them excellent photosensitizer candidates for photodynamic therapy.

scholarly journals In Vitro Effect of Photodynamic Therapy with Different Lights and Combined or Uncombined with Chlorhexidine on Candida spp.

Pharmaceutics ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1176
Author(s):  
Vanesa Pérez-Laguna ◽  
Yolanda Barrena-López ◽  
Yolanda Gilaberte ◽  
Antonio Rezusta
Keyword(s):  
Photodynamic Therapy ◽  
Light Emitting Diode ◽  
Antimicrobial Effect ◽  
Photodynamic Treatment ◽  
Candida Spp ◽  
Promising Alternative ◽  
Light Emitting ◽  
Colony Forming Units ◽  
Vitro Effect

Candidiasis is very common and complicated to treat in some cases due to increased resistance to antifungals. Antimicrobial photodynamic therapy (aPDT) is a promising alternative treatment. It is based on the principle that light of a specific wavelength activates a photosensitizer molecule resulting in the generation of reactive oxygen species that are able to kill pathogens. The aim here is the in vitro photoinactivation of three strains of Candida spp., Candida albicans ATCC 10231, Candida parapsilosis ATCC 22019 and Candida krusei ATCC 6258, using aPDT with different sources of irradiation and the photosensitizer methylene blue (MB), alone or in combination with chlorhexidine (CHX). Irradiation was carried out at a fluence of 18 J/cm2 with a light-emitting diode (LED) lamp emitting in red (625 nm) or a white metal halide lamp (WMH) that emits at broad-spectrum white light (420–700 nm). After the photodynamic treatment, the antimicrobial effect is evaluated by counting colony forming units (CFU). MB-aPDT produces a 6 log10 reduction in the number of CFU/100 μL of Candida spp., and the combination with CHX enhances the effect of photoinactivation (effect achieved with lower concentration of MB). Both lamps have similar efficiencies, but the WMH lamp is slightly more efficient. This work opens the doors to a possible clinical application of the combination for resistant or persistent forms of Candida infections.

scholarly journals Red and Near-Infrared Absorbing Dicyanomethylene Squaraine Cyanine Dyes: Photophysicochemical Properties and Anti-Tumor Photosensitizing Effects

Materials ◽  
2020 ◽  
Vol 13 (9) ◽  
pp. 2083
Author(s):  
Tiago D. Martins ◽  
Eurico Lima ◽  
Renato E. Boto ◽  
Diana Ferreira ◽  
José R. Fernandes ◽  
...  
Keyword(s):  
Singlet Oxygen ◽  
Near Infrared ◽  
Cyanine Dyes ◽  
Quantum Yields ◽  
Squaraine Dyes ◽  
Photodynamic Activity ◽  
Photochemical Properties ◽  
Radiation Treatments ◽  
Species Production

Photodynamic therapy is a medical modality developed for the treatment of several diseases of oncological and non-oncological etiology that requires the presence of a photosensitizer, light and molecular oxygen, which combined will trigger physicochemical reactions responsible for reactive oxygen species production. Given the scarcity of photosensitizers that exhibit desirable characteristics for its potential application in this therapeutic strategy, the main aims of this work were the study of the photophysical and photochemical properties and the photobiological activity of several dicyanomethylene squaraine cyanine dyes. Thus, herein, the study of their aggregation character, photobleaching and singlet oxygen production ability, and the further application of the previously synthesized dyes in Caco-2 and HepG2 cancer cell lines, to evaluate their phototherapeutic effects, are described. Dicyanomethylene squaraine dyes exhibited moderate light-stability and, despite the low singlet oxygen quantum yields, were a core of dyes that exhibited relevant in vitro photodynamic activity, as there was an evident increase in the toxicity of some of the tested dyes exclusive to radiation treatments.

scholarly journals Toluidine blue O and porphyrin-mediated photodynamic therapy on three main pathogenic bacteria of periodontitis using portable LED phototherapy device

2015 ◽  
Vol 08 (04) ◽  
pp. 1550017 ◽  
Author(s):  
Xuewei Jiang ◽  
Zhichao Fan ◽  
Yili Yu ◽  
Chenying Shao ◽  
Yuanzhen Suo ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Toluidine Blue ◽  
Pathogenic Bacteria ◽  
Light Emitting Diode ◽  
Red Light ◽  
In Vitro Screening ◽  
Light Emitting ◽  
Led Phototherapy ◽  
Prevotella Melaninogenica

Photodynamic therapy (PDT) has been commonly used in treating many diseases, such as cancer and infectious diseases. We investigated the different effects of PDT on three main pathogenic bacteria of periodontitis — Prevotella melaninogenica (P.m.), Porphyromonas gingivalis (P.g.) and Aggregatibacter actinomycetemcomitans (A.a.). The portable red light-emitting diode (LED) phototherapy device was used to assess the exogenous PDT effects with different light doses and photosensitizer concentrations (Toluidine blue O, TBO). The portable blue LED phototherapy device was used to assess the endogenous PDT effects with the use of endogenous photosensitizers (porphyrin) under different light doses. We found out that both exogenous and endogenous PDT were able to restrict the growth of all the three bacteria significantly. Moreover, the optimal PDT conditions for these bacteria were obtained through this in vitro screening and could guide the clinical PDT on periodontitis.

Quinolin-8-yloxy-substituted zinc(II) phthalocyanines for enhanced in vitro photodynamic therapy

2018 ◽  
Vol 22 (09n10) ◽  
pp. 807-813 ◽  
Author(s):  
Juanjuan Chen ◽  
Yuting Fang ◽  
Hong Liu ◽  
Naisheng Chen ◽  
Shengping Chen ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Singlet Oxygen ◽  
Clinical Application ◽  
Cellular Uptake ◽  
Culture Medium ◽  
Anticancer Agent ◽  
Quantum Yields ◽  
Anticancer Efficacy ◽  
Self Aggregation

Photodynamic therapy (PDT) is an innovative and promising modality to treat various tumors. In this study, two novel zinc(II) phthalocyanines substituted with quinolin-8-yloxy groups at the [Formula: see text]-position, namely mono(quinolin-8-yloxy) zinc(II) phthalocyanine (ZnPc-Q1) and tetra(quinolin-8-yloxy) zinc(II) phthalocyanine (ZnPc-Q4), have been synthesized and fully characterized. With quinolin-8-yloxy, these two phthalocyanines exhibit less self-aggregation in DMF and culture medium, high singlet oxygen quantum yields, mitochondria localization and high photodynamic activities (IC[Formula: see text] values as low as 2 nM). Compared to ZnPc-Q4, ZnPc-Q1 exhibits higher cellular uptake and lower IC[Formula: see text] values. Benefitting from its higher anticancer efficacy and lack of isomers, ZnPc-Q1 is a highly promising anticancer agent in clinical application.

Photophysicochemical properties and photodynamic therapy activity of chloroindium(III) tetraarylporphyrins and their gold nanoparticle conjugates

2019 ◽  
Vol 23 (01n02) ◽  
pp. 34-45 ◽  
Author(s):  
Rodah C. Soy ◽  
Balaji Babu ◽  
David O. Oluwole ◽  
Njemuwa Nwaji ◽  
James Oyim ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Quantum Yield ◽  
Singlet Oxygen ◽  
Dose Range ◽  
Heavy Atom ◽  
Therapeutic Window ◽  
Quantum Yields ◽  
Yield Values ◽  
Yield Formula

Novel chloroindium(III) complexes of tetra(4-methylthiophenyl)porphyrin (2a) and tetra-2-thienylporphyrin (2b) dyes have been synthesized and characterized. The main goal of the project was to identify fully symmetric porphyrin dyes with Q-band regions that lie partially in the therapeutic window that are suitable for use in photodynamic therapy (PDT). 2a and 2b were found to have fluorescence quantum yield values [Formula: see text] 0.01 and moderately high singlet oxygen quantum yields (0.54−0.73) due to heavy atom effects associated with the sulfur and indium atoms. The dark toxicity and PDT activity against epithelial breast cancer cells (MCF-7) were investigated over a dose range of 3.0−40 [Formula: see text]g [Formula: see text] mL[Formula: see text]. The in vitro dark cytotoxicity of 2a is significantly lower than that of 2b at [Formula: see text] 40 [Formula: see text]g [Formula: see text] mL[Formula: see text]. 2a was conjugated with gold nanoparticles (AuNPs) to form a nanoconjugate (2a-AuNPs), which exhibited a higher singlet oxygen quantum yield ([Formula: see text] value and PDT activity than was observed for 2a alone. The results suggest that the AuNPs nanoconjugates of readily synthesized fully symmetric porphyrin dyes are potentially suitable for PDT applications, if meso-aryl substituents that provide scope for nanoparticle conjugation can be introduced that shift the Q bands into the therapeutic window.

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

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
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.

Sign in / Sign up

Export Citation Format

Share Document