Author
Maria A. F. Faustino
Other affiliations: Autonomous University of Madrid
Bio: Maria A. F. Faustino is an academic researcher from University of Aveiro. The author has contributed to research in topics: Porphyrin & Photosensitizer. The author has an hindex of 37, co-authored 146 publications receiving 4393 citations. Previous affiliations of Maria A. F. Faustino include Autonomous University of Madrid.
Topics: Porphyrin, Photosensitizer, Photodynamic therapy, Chemistry, Medicine
Papers published on a yearly basis
Papers
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TL;DR: The results suggest that aPDT using Tri-Py+-Me-PF represents a promising approach to efficiently destroy bacteria since after a single treatment these microorganisms do not recover their viability and after ten generations of partially photosensitized cells neither of the bacteria develop resistance to the photodynamic process.
Abstract: Antimicrobial photodynamic therapy (aPDT) has emerged in the clinical field as a potential alternative to antibiotics to treat microbial infections. No cases of microbial viability recovery or any resistance mechanisms against it are yet known. 5,10,15-tris(1-Methylpyridinium-4-yl)-20-(pentafluorophenyl)-porphyrin triiodide (Tri-Py(+)-Me-PF) was used as photosensitizer. Vibrio fischeri and recombinant Escherichia coli were the studied bacteria. To determine the bacterial recovery after treatment, Tri-Py(+)-Me-PF (5.0 microM) was added to bacterial suspensions and the samples were irradiated with white light (40 W m(-2)) for 270 minutes. Then, the samples were protected from light, aliquots collected at different intervals and the bioluminescence measured. To assess the development of resistance after treatment, bacterial suspensions were exposed to white light (25 minutes), in presence of 5.0 microM of Tri-Py(+)-Me-PF (99.99% of inactivation) and plated. After the first irradiation period, surviving colonies were collected from the plate and resuspended in PBS. Then, an identical protocol was used and repeated ten times for each bacterium. The results suggest that aPDT using Tri-Py(+)-Me-PF represents a promising approach to efficiently destroy bacteria since after a single treatment these microorganisms do not recover their viability and after ten generations of partially photosensitized cells neither of the bacteria develop resistance to the photodynamic process.
351 citations
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TL;DR: The complete inactivation of both bacterial strains with low light fluence means that the photodynamic approach can be applied to wastewater treatment under natural light conditions which makes this technology cheap and feasible in terms of the light source.
Abstract: In recent times photodynamic antimicrobial therapy has been used to efficiently destroy Gram (+) and Gram (-) bacteria using cationic porphyrins as photosensitizers. There is an increasing interest in this approach, namely in the search of photosensitizers with adequate structural features for an efficient photoinactivation process. In this study we propose to compare the efficiency of seven cationic porphyrins differing in meso-substituent groups, charge number and charge distribution, on the photodynamic inactivation of a Gram (+) bacterium (Enterococcus faecalis) and of a Gram (-) bacterium (Escherichia coli). The present study complements our previous work on the search for photosensitizers that might be considered good candidates for the photoinactivation of a large spectrum of environmental microorganisms. Bacterial suspension (107 CFU mL-1) treated with different photosensitizers concentrations (0.5, 1.0 and 5.0 μM) were exposed to white light (40 W m-2) for a total light dose of 64.8 J cm-2. The most effective photosensitizers against both bacterial strains were the Tri-Py+-Me-PF and Tri-Py+-Me-CO2Me at 5.0 μM with a light fluence of 64.8 J cm-2, leading to > 7.0 log (> 99,999%) of photoinactivation. The tetracationic porphyrin also proved to be a good photosensitizer against both bacterial strains. Both di-cationic and the monocationic porphyrins were the least effective ones. The number of positive charges, the charge distribution in the porphyrins' structure and the meso-substituent groups seem to have different effects on the photoinactivation of both bacteria. As the Tri-Py+-Me-PF porphyrin provides the highest log reduction using lower light doses, this photosensitizer can efficiently photoinactivate a large spectrum of environmental bacteria. The complete inactivation of both bacterial strains with low light fluence (40 W m-2) means that the photodynamic approach can be applied to wastewater treatment under natural light conditions which makes this technology cheap and feasible in terms of the light source.
200 citations
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TL;DR: The aim of this review is to discuss and compare the present state of the art of mammalian viruses PDI with phage photoinactivation, with special focus on the most relevant mechanisms, molecular targets and factors affecting the viral inactivation process.
Abstract: Photodynamic inactivation (PDI) has been used to inactivate microorganisms through the use of photosensitizers. The inactivation of mammalian viruses and bacteriophages by photosensitization has been applied with success since the first decades of the last century. Due to the fact that mammalian viruses are known to pose a threat to public health and that bacteriophages are frequently used as models of mammalian viruses, it is important to know and understand the mechanisms and photodynamic procedures involved in their photoinactivation. The aim of this review is to (i) summarize the main approaches developed until now for the photodynamic inactivation of bacteriophages and mammalian viruses and, (ii) discuss and compare the present state of the art of mammalian viruses PDI with phage photoinactivation, with special focus on the most relevant mechanisms, molecular targets and factors affecting the viral inactivation process.
184 citations
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TL;DR: The efforts made in the last decade in the investigation of PDI of (micro)organisms with potential applications beyond the medical field will be discussed, focusing on porphyrins, free or immobilized on solid supports, as photosensitizing agents.
Abstract: Although the discovery of light-activated antimicrobial agents had been reported in the 1900s, only more recently research work has been developed toward the use of photodynamic process as an alternative to more conventional methods of inactivation of micro(organisms). The photoprocess causes cell death through irreversible oxidative damage by reactive oxygen species produced by the interaction between a photosensitizing compound and a light source. With great emphasis on the environmental area, photodynamic inactivation (PDI) has been tested in insect eradication and in water disinfection. Lately, other studies have been carried out concerning its possible use in aquaculture waters or to the control of food-borne pathogens. Other potential applications of PDI in household, industrial and hospital settings have been considered. In the last decade, scientific research in this area has gained importance not only due to great developments in the field of materials chemistry but also because of the serious problem of the increasing number of bacterial species resistant to common antibiotics. In fact, the design of antimicrobial surfaces or self-cleaning materials is a very appealing idea from the economic, social and public health standpoints. Thus, PDI of micro(organisms) represents a promising alternative. In this review, the efforts made in the last decade in the investigation of PDI of (micro)organisms with potential applications beyond the medical field will be discussed, focusing on porphyrins, free or immobilized on solid supports, as photosensitizing agents.
177 citations
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TL;DR: The aim of this review is to briefly present the typical fish farming diseases and their threats and discuss the present state of chemotherapy to inactivate microorganisms in fish farming plants as well as to examine the new environmentally friendly approaches to control fish infection namely phage therapy and photodynamic antimicrobial therapy.
Abstract: Owing to the increasing importance of aquaculture to compensate for the progressive worldwide reduction of natural fish and to the fact that several fish farming plants often suffer from heavy financial losses due to the development of infections caused by microbial pathogens, including multidrug resistant bacteria, more environmentally-friendly strategies to control fish infections are urgently needed to make the aquaculture industry more sustainable. The aim of this review is to briefly present the typical fish farming diseases and their threats and discuss the present state of chemotherapy to inactivate microorganisms in fish farming plants as well as to examine the new environmentally friendly approaches to control fish infection namely phage therapy and photodynamic antimicrobial therapy.
142 citations
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TL;DR: The attributes of BODIPY dyes for PDT are summarized, and substituents with appropriate oxidation potentials are summarized in some related areas.
Abstract: BODIPY dyes tend to be highly fluorescent, but their emissions can be attenuated by adding substituents with appropriate oxidation potentials. Substituents like these have electrons to feed into photoexcited BODIPYs, quenching their fluorescence, thereby generating relatively long-lived triplet states. Singlet oxygen is formed when these triplet states interact with 3O2. In tissues, this causes cell damage in regions that are illuminated, and this is the basis of photodynamic therapy (PDT). The PDT agents that are currently approved for clinical use do not feature BODIPYs, but there are many reasons to believe that this situation will change. This review summarizes the attributes of BODIPY dyes for PDT, and in some related areas.
1,599 citations
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TL;DR: The historical development and current state of the art in this rapidly expanding field of research is summarized, which has become one of the key exploration areas of modern heterocyclic chemistry.
Abstract: Two-dimensionally extended, polycyclic heteroaromatic molecules (heterocyclic nanographenes) are a highly versatile class of organic materials, applicable as functional chromophores and organic semiconductors. In this Review, we discuss the rich chemistry of large heteroaromatics, focusing on their synthesis, electronic properties, and applications in materials science. This Review summarizes the historical development and current state of the art in this rapidly expanding field of research, which has become one of the key exploration areas of modern heterocyclic chemistry.
823 citations
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TL;DR: Antioxidant defenses against ROS in microbial cells and the use of ROS by antimicrobial host defense systems are covered and reactive nitrogen species and related therapeutics, such as acidified nitrite and nitric oxide-releasing nanoparticles are covered.
Abstract: Reactive oxygen species (ROS) can attack a diverse range of targets to exert antimicrobial activity, which accounts for their versatility in mediating host defense against a broad range of pathogens. Most ROS are formed by the partial reduction in molecular oxygen. Four major ROS are recognized comprising superoxide (O2•-), hydrogen peroxide (H2O2), hydroxyl radical (•OH), and singlet oxygen ((1)O2), but they display very different kinetics and levels of activity. The effects of O2•- and H2O2 are less acute than those of •OH and (1)O2, because the former are much less reactive and can be detoxified by endogenous antioxidants (both enzymatic and nonenzymatic) that are induced by oxidative stress. In contrast, no enzyme can detoxify •OH or (1)O2, making them extremely toxic and acutely lethal. The present review will highlight the various methods of ROS formation and their mechanism of action. Antioxidant defenses against ROS in microbial cells and the use of ROS by antimicrobial host defense systems are covered. Antimicrobial approaches primarily utilizing ROS comprise both bactericidal antibiotics and nonpharmacological methods such as photodynamic therapy, titanium dioxide photocatalysis, cold plasma, and medicinal honey. A brief final section covers reactive nitrogen species and related therapeutics, such as acidified nitrite and nitric oxide-releasing nanoparticles.
744 citations
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TL;DR: The aim of reproducing some of the fundamental steps occurring in natural photosynthesis, one of the most important being the photoinduced charge separation (CS), are reproduced.
Abstract: Photosynthesis is used by nature to convert light energy into chemical energy in some living systems. In such a process, a cascade of very efficient, short-range energy and electron transfer events between well-arranged, light-harvesting organic donor and acceptor pigments takes place within the photosynthetic reaction center, leading to the overall generation of chemical energy from sunlight with near quantum efficiency.1-8 During the past decade, a significant effort has been made by the scientific community toward the preparation of synthetic model compounds of natural photosynthetic systems able to convert light into other energy sources,9 probably fostered by the increasing concerns related to the utilization of fossils fuels for the production of electricity in terms of both availability and environmental issues. However, considering the structural complexity presented by the natural photosynthetic systems, much of the scientific effort has been devoted toward the preparation and study of structurally simpler systems, with the aim of reproducing some of the fundamental steps occurring in natural photosynthesis, one of the most important being the photoinduced charge separation (CS).10-12 Among the chromophores that have been used as molecular components in artificial photosynthetic systems, porphyrinoids, the ubiquitous molecular building blocks employed by nature in natural photosynthesis, have been the preferred and obvious choice, due to their intense optical absorption and rich redox chemistry.13-20 Within the large family of porphyrinoid systems, phthalocyanines (Pcs) enjoy a privileged position (Figure 1a). These chromophores, which have a two-dimensional 18-πelectron aromatic system isoelectronic with that of porphyrins (Pors), possess in fact unique physicochemical properties which render these macrocycles valuable building blocks in materials science.21-32 Pcs are thermally and chemically stable compounds which present an intense absorption in the red/near-infrared (IR) region of the solar spectrum with extinction coefficients (as high as 200 000 M-1 cm-1) and fluorescence quantum yields * To whom correspondence should be addressed. E-mail: tomas.torres@uam.es (T.T.); dirk.guldi@chemie.uni-erlangen.de (D.M.G.). † Universidad Autonoma de Madrid. ‡ Friedrich-Alexander-Universitat Erlangen-Nurnberg. § IMDEA-Nanociencia. Chem. Rev. 2010, 110, 6768–6816 6768
731 citations
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TL;DR: The roles of porphyrinic molecules in imaging and pdt, along with research into improving their selective uptake in diseased tissue and their utility in theranostic applications are highlighted in this Review.
Abstract: Porphyrinic molecules have a unique theranostic role in disease therapy; they have been used to image, detect and treat different forms of diseased tissue including age-related macular degeneration and a number of different cancer types. Current focus is on the clinical imaging of tumour tissue; targeted delivery of photosensitisers and the potential of photosensitisers in multimodal biomedical theranostic nanoplatforms. The roles of porphyrinic molecules in imaging and pdt, along with research into improving their selective uptake in diseased tissue and their utility in theranostic applications are highlighted in this Review.
480 citations