59 results match your criteria inactivation apdi


Toward Universal Photodynamic Coatings for Infection Control.

Front Med (Lausanne) 2021 28;8:657837. Epub 2021 Jul 28.

Department of Chemistry, North Carolina State University, Raleigh, NC, United States.

The dual threats posed by the COVID-19 pandemic and hospital-acquired infections (HAIs) have emphasized the urgent need for self-disinfecting materials for infection control. Despite their highly potent antimicrobial activity, the adoption of photoactive materials to reduce infection transmission in hospitals and related healthcare facilities has been severely hampered by the lack of scalable and cost-effective manufacturing, in which case high-volume production methods for fabricating aPDI-based materials are needed. To address this issue here, we examined the antimicrobial efficacy of a simple bicomponent spray coating composed of the commercially-available UV-photocrosslinkable polymer -methyl-4(4'-formyl-styryl)pyridinium methosulfate acetal poly(vinyl alcohol) (SbQ-PVA) and one of three aPDI photosensitizers (PSs): zinc-tetra(4--methylpyridyl)porphine (ZnTMPyP), methylene blue (MB), and Rose Bengal (RB). Read More

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Broad-Spectrum Photo-Antimicrobial Polymers Based on Cationic Polystyrene and Rose Bengal.

Front Med (Lausanne) 2021 24;8:641646. Epub 2021 May 24.

Departamento de Química Inorgánica y Orgánica, Universitat Jaume I, Castellón, Spain.

New strategies to fight bacteria and fungi are necessary in view of the problem of iatrogenic and nosocomial infections combined with the growing threat of increased antimicrobial resistance. Recently, our group has prepared and described two new readily available materials based on the combination of Rose Bengal (singlet oxygen photosensitizer) and commercially available cationic polystyrene (macroporous resin Amberlite® IRA 900 or gel-type resin IRA 400). These materials showed high efficacy in the antimicrobial photodynamic inactivation (aPDI) of . Read More

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Antimicrobial Photodynamic Inactivation Using Topical and Superhydrophobic Sensitizer Techniques: A Perspective from Diffusion in Biofilms.

Photochem Photobiol 2021 Jun 7. Epub 2021 Jun 7.

Ph.D. Program in Chemistry, The Graduate Center of the City University of New York, New York, NY, USA.

This review describes nanoparticle and dye diffusion in bacterial biofilms in the context of antimicrobial photodynamic inactivation (aPDI). aPDI requires the diffusion of a photosensitizer (Sens) into the biofilm and subsequent photoactivation of oxygen for the generation of reactive oxygen species (ROS) that inactivate microbes. Molecular diffusion in biofilms has been long investigated, whereas this review is intended to draw a logical link between diffusion in biofilms and ROS, a combination that leads to the current state of aPDI and superhydrophobic aPDI (SH-aPDI). Read More

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Antimicrobial Photodynamic Inactivation Affects the Antibiotic Susceptibility of spp. Clinical Isolates in Biofilm and Planktonic Cultures.

Biomolecules 2021 05 5;11(5). Epub 2021 May 5.

Laboratory of Molecular Diagnostics, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, 80-307 Gdansk, Poland.

and are opportunistic pathogens that can cause a vast variety of nosocomial infections. Moreover, belongs to the group of ESKAPE microbes, which are the main cause of hospital-acquired infections and are especially difficult to treat because of their resistance to many antibiotics. Antimicrobial photodynamic inactivation (aPDI) represents an alternative to overcome multidrug resistance problems. Read More

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Factors Determining the Susceptibility of Bacteria to Antibacterial Photodynamic Inactivation.

Front Med (Lausanne) 2021 12;8:642609. Epub 2021 May 12.

Laboratory of Molecular Diagnostics, Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, Gdańsk, Poland.

Photodynamic inactivation of microorganisms (aPDI) is an excellent method to destroy antibiotic-resistant microbial isolates. The use of an exogenous photosensitizer or irradiation of microbial cells already equipped with endogenous photosensitizers makes aPDI a convenient tool for treating the infections whenever technical light delivery is possible. Currently, aPDI research carried out on a vast repertoire of depending on the photosensitizer used, the target microorganism, and the light delivery system shows efficacy mostly on models. Read More

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Effective Photodynamic Therapy with Ir(III) for Virulent Clinical Isolates of Extended-Spectrum Beta-Lactamase .

Pharmaceutics 2021 Apr 22;13(5). Epub 2021 Apr 22.

Laboratorio de Microbiología Celular, Instituto de Investigación y Postgrado, Facultad de Ciencias de la Salud, Universidad Central de Chile, Santiago 8330546, Chile.

Background: The extended-spectrum beta-lactamase (ESBL) is one of the leading causes of health-associated infections (HAIs), whose antibiotic treatments have been severely reduced. Moreover, HAI bacteria may harbor pathogenic factors such as siderophores, enzymes, or capsules, which increase the virulence of these strains. Thus, new therapies, such as antimicrobial photodynamic inactivation (aPDI), are needed. Read More

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Cationic zinc (II) phthalocyanine nanoemulsions for photodynamic inactivation of resistant bacterial strains.

Photodiagnosis Photodyn Ther 2021 Jun 21;34:102301. Epub 2021 Apr 21.

Pharmaceutical Technology Laboratory, Department of Medical Applications of Laser, National Institute of Laser Enhanced Sciences (NILES), Cairo University, Cairo, Egypt.

Background: The growing emergence of microbial resistance to antibiotics represents a worldwide challenge. Antimicrobial photodynamic inactivation (aPDI) has been introduced as an alternative technique, especially when combined with nanotechnology. Therefore, this study was designed to investigate the therapeutic merits of combined aPDI and nanoemulsion in infections caused by resistant bacterial strains. Read More

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Development of Antimicrobial Phototreatment Tolerance: Why the Methodology Matters.

Int J Mol Sci 2021 Feb 23;22(4). Epub 2021 Feb 23.

Laboratory of Molecular Diagnostics, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307 Gdansk, Poland.

Due to rapidly growing antimicrobial resistance, there is an urgent need to develop alternative, non-antibiotic strategies. Recently, numerous light-based approaches, demonstrating killing efficacy regardless of microbial drug resistance, have gained wide attention and are considered some of the most promising antimicrobial modalities. These light-based therapies include five treatments for which high bactericidal activity was demonstrated using numerous in vitro and in vivo studies: antimicrobial blue light (aBL), antimicrobial photodynamic inactivation (aPDI), pulsed light (PL), cold atmospheric plasma (CAP), and ultraviolet (UV) light. Read More

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February 2021

Synergistic effect of hypocrellin B and curcumin on photodynamic inactivation of Staphylococcus aureus.

Microb Biotechnol 2021 03 19;14(2):692-707. Epub 2021 Jan 19.

School of Food and Bioengineering, Hefei University of Technology, Hefei, 230009, China.

Antimicrobial photodynamic inactivation (aPDI) serves as a new approach to control the growth of foodborne bacteria. It remains elusive if the photodynamic efficacy of hypocrellin B (HB) can be potentiated by joint action with curcumin. In this study, we measured the survival rate of Staphylococcus aureus strains under the varying photodynamic conditions. Read More

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The application of antimicrobial photodynamic inactivation on methicillin-resistant S. aureus and ESBL-producing K. pneumoniae using porphyrin photosensitizer in combination with silver nanoparticles.

Photodiagnosis Photodyn Ther 2021 Mar 8;33:102140. Epub 2020 Dec 8.

Department of Medical Biophysics, Faculty of Medicine and Dentistry, Palacky University in Olomouc, Czech Republic; Department of Medical Biophysics, Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University in Olomouc, Czech Republic. Electronic address:

As resistance of bacterial strains to antibiotics is a major problem, there is a need to look for alternative treatments. One option is antimicrobial photodynamic inactivation (aPDI). The pathogenic cells are targeted by a nontoxic photosensitizer while the surrounding healthy tissue is relatively unaffected. Read More

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Antimicrobial carbon nanodots: photodynamic inactivation and dark antimicrobial effects on bacteria by brominated carbon nanodots.

Nanoscale 2021 Jan 19;13(1):85-99. Epub 2020 Nov 19.

Institute of Fluorescence and Department of Chemistry and Biochemistry, University of Maryland Baltimore County, 701 East Pratt Street, Baltimore, Maryland 21202, USA.

The evolving threat of antibiotic resistance development in pathogenic bacteria necessitates the continued cultivation of new technologies and agents to mitigate associated negative health impacts globally. It is no surprise that infection prevention and control are cited by the Centers for Disease Control and Prevention (CDC) as two routes for combating this dangerous trend. One technology that has gained great research interest is antimicrobial photodynamic inactivation of bacteria, or APDI. Read More

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January 2021

Validation of stable reference genes in Staphylococcus aureus to study gene expression under photodynamic treatment: a case study of SEB virulence factor analysis.

Sci Rep 2020 10 1;10(1):16354. Epub 2020 Oct 1.

Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307, Gdansk, Poland.

Staphylococcal enterotoxin B (SEB), encoded by the seb gene, is a virulence factor produced by Staphylococcus aureus that is involved mainly in food poisoning and is known to act as an aggravating factor in patients with atopic dermatitis. Research results in animal infection models support the concept that superantigens, including SEB contribute to sepsis and skin and soft tissue infections. In contrast to antibiotics, antimicrobial photodynamic inactivation (aPDI) is a promising method to combat both bacterial cells and virulence factors. Read More

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October 2020

Photodynamic Inactivation of Methicillin-Resistant by a Natural Food Colorant (E-141ii).

Molecules 2020 Sep 29;25(19). Epub 2020 Sep 29.

School of Life Sciences, University of Essex, Colchester CO4 3SQ, UK.

This study evaluates the photosensitizing effectiveness of sodium copper chlorophyllin, a natural green colorant commonly used as a food additive (E-141ii), to inactivate methicillin-sensitive and methicillin-resistant under red-light illumination. Antimicrobial photodynamic inactivation (aPDI) was tested on a methicillin-sensitive reference strain (ATCC 25923) and a methicillin-resistant strain (GenBank accession number Mh087437) isolated from a clinical sample. The photoinactivation efficacy was investigated by exposing the bacterial strains to different E-141ii concentrations (0. Read More

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September 2020

The mode of action of the PSIR-3 photosensitizer in the photodynamic inactivation of Klebsiella pneumoniae is by the production of type II ROS which activate RpoE-regulated extracytoplasmic factors.

Photodiagnosis Photodyn Ther 2020 Dec 22;32:102020. Epub 2020 Sep 22.

Laboratorio de Microbiología Celular, Instituto de Investigación e Innovación en Salud, Facultad de Ciencias de la Salud, Universidad Central de Chile, Lord Cochrane 418, Post Cod: 8330546, Santiago, Chile. Electronic address:

Background: Due to increased bacterial multi-drug resistance (MDR), there is an antibiotic depletion to treat infectious diseases. Consequently, other promising options have emerged, such as the antimicrobial photodynamic inactivation therapy (aPDI) based on photosensitizer (PS) compounds to produce light-activated local oxidative stress (photooxidative stress). However, there are scarce studies regarding the mode of action of PS compounds to induce photooxidative stress on pathogenic γ-proteobacteria such as MDR-Klebsiella pneumoniae. Read More

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December 2020

Chitosan enhances the antimicrobial photodynamic inactivation mediated by Photoditazine® against Streptococcus mutans.

Photodiagnosis Photodyn Ther 2020 Dec 19;32:102001. Epub 2020 Sep 19.

Department of Biosciences and Oral Diagnosis, Institute of Science and Technology, São Paulo State University/UNESP, São José dos Campos, SP, Brazil. Electronic address:

Chitosan (CS), a biopolymer with intrinsic antimicrobial activity, can increase antimicrobial photodynamic inactivation (aPDI). The aim of this study was to evaluate the capacity of CS to potentiate the efficacy of Photoditazine® (PDZ)-mediated aPDI of the cariogenic bacterium Streptococcus mutans. CS effectively augmented the effects of aPDI, with reductions of approximately 4. Read More

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December 2020

Increased photoinactivation stress tolerance of Streptococcus agalactiae upon consecutive sublethal phototreatments.

Free Radic Biol Med 2020 11 8;160:657-669. Epub 2020 Sep 8.

Intercollegiate Faculty of Biotechnology, Laboratory of Molecular Diagnostics, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307, Gdansk, Poland. Electronic address:

Streptococcus agalactiae (Group B Streptococcus, GBS) is a common commensal bacterium in adults but remains a leading source of invasive infections in newborns, pregnant women, and the elderly, and more recently, causes an increased incidence of invasive disease in nonpregnant adults. Reduced penicillin susceptibility and emerging resistance to non-β-lactams pose challenges for the development and implementation of novel, nonantimicrobial strategies to reduce the burden of GBS infections. Antimicrobial photodynamic inactivation (aPDI) via the production of singlet oxygen or other reactive oxygen species leads to the successful eradication of pathogenic bacteria, affecting numerous cellular targets of microbial pathogens and indicating a low risk of resistance development. Read More

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November 2020

Monosubstituted tricationic Zn(II) phthalocyanine enhances antimicrobial photodynamic inactivation (aPDI) of methicillin-resistant (MRSA) and cytotoxicity evaluation for topical applications: and study.

Emerg Microbes Infect 2020 Dec;9(1):1628-1637

Department of Microbiology, Faculty of Medicine, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong (SAR), People's Republic of China.

Antimicrobial photodynamic therapy (aPDT) is an innovative approach to combat multi-drug resistant bacteria. It is known that cationic Zn(II) phthalocyanines (ZnPc) are effective in mediating aPDT against methicillin-resistant (MRSA). Here we used ZnPc-based photosensitizer named ZnPcE previously reported by our research group to evaluate its aPDT efficacy against broad spectrum of clinically relevant MRSAs. Read More

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December 2020

Insight into light-driven antibacterial cotton fabrics decorated by in situ growth strategy.

J Colloid Interface Sci 2020 Nov 10;579:233-242. Epub 2020 Jun 10.

Key Laboratory of Eco-Textiles, Ministry of Education, Jiangnan University, Wuxi 214122, China; Fujian Key Laboratory of Novel Functional Textile Fibers and Materials, Minjiang University, Fuzhou, Fujian 350108, China. Electronic address:

Development of ease-fabricated and effectively self-disinfecting textile materials for antimicrobial and infection prevention has been urgently desired by both consumers and industry. However, some nonresponsive antibacterial agents finished fabrics may be harmful to human. To address this issue, we developed a facile finishing method to endow woven cotton fabrics (WCF) with light-driven antibacterial property. Read More

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November 2020

Synergistic effect of combined imipenem and photodynamic treatment with the cationic Ir(III) complexes to polypyridine ligand on carbapenem-resistant Klebsiella pneumoniae.

Photodiagnosis Photodyn Ther 2020 Sep 18;31:101882. Epub 2020 Jun 18.

Laboratorio de Microbiología Celular, Instituto de Investigación e Innovación en Salud, Facultad de Ciencias de la Salud, Universidad Central de Chile, Lord Cochrane 418, 8330546, Santiago, Chile. Electronic address:

Background: Carbapenemase-producing strains of Klebsiella pneumoniae (KPC) are one of the multi-drug resistant bacteria with the highest risk for human health. The colistin is the only antibiotic option against KPC; however, due to its emerging resistance, therapies such as antimicrobial photodynamic inactivation (aPDI), are needed. APDI uses photosensitizer compounds (PS) to produce light-activated local oxidative stress (photooxidative stress). Read More

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September 2020

Carbon quantum dots: A bright future as photosensitizers for in vitro antibacterial photodynamic inactivation.

J Photochem Photobiol B 2020 Mar 23;206:111864. Epub 2020 Mar 23.

Key Laboratory of Eco-Textiles, Ministry of Education, Jiangnan University, Wuxi 214122, China; Fujian Key Laboratory of Novel Functional Textile Fibers and Materials, Minjiang University, Fuzhou, Fujian 350108, China. Electronic address:

Carbon nanomaterials have increasingly gained the attention of the nano-, photo- and biomedical communities owing to their unique photophysical properties. Here, we facilely synthesized carbon quantum dots (CQDs) in a one-pot solvothermal reaction, and demonstrated their utility as photosensitizers for in vitro antibacterial photodynamic inactivation (aPDI). The bottom-up synthesis employed inexpensive and sustainable starting materials (citric acid), used ethanol as an environmentally-friendly solvent, was relatively energy efficient, produced minimal waste, and purification was accomplished simply by filtration. Read More

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Nano adamantane-conjugated BODIPY for lipase affinity and light driven antibacterial.

Spectrochim Acta A Mol Biomol Spectrosc 2020 Jun 13;234:118252. Epub 2020 Mar 13.

School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, China; THOR Specialty Chemical (Zhenjiang) Company Limited, No. 182 Jingang Avenue, New District, Zhenjiang, Jiangsu 212132, China.

The increasing number of resistant bacterial strains has raised efforts in developing alternative treatment strategies. Lipase is highly expressed in most bacteria and lipase targeting dyes will be non-sacrificed materials for a sustainable method against microorganism. The combination of chemotherapy and antimicrobial photodynamic inactivation (aPDI) method will be an effective method due to enhanced antibacterial activity. Read More

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Genetically Encoded Photosensitizers as Light-Triggered Antimicrobial Agents.

Int J Mol Sci 2019 Sep 17;20(18). Epub 2019 Sep 17.

Institute of Molecular Enzyme Technology, Heinrich-Heine-University Düsseldorf, Forschungszentrum Jülich GmbH, D-52428 Jülich, Germany.

Diseases caused by multi-drug resistant pathogens have become a global concern. Therefore, new approaches suitable for treating these bacteria are urgently needed. In this study, we analyzed genetically encoded photosensitizers (PS) related to the green fluorescent protein (GFP) or light-oxygen-voltage (LOV) photoreceptors for their exogenous applicability as light-triggered antimicrobial agents. Read More

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September 2019

Sub-lethal antimicrobial photodynamic inactivation affects Pseudomonas aeruginosa PAO1 quorum sensing and cyclic di-GMP regulatory systems.

Photodiagnosis Photodyn Ther 2019 Sep 27;27:467-473. Epub 2019 Jul 27.

Department of Microbiology, School of Biology, College of Science, University of Tehran, Tehran, Iran. Electronic address:

Background: Antimicrobial photodynamic inactivation (APDI) is a new therapeutic modality which needs more precision during application due to the possibility of exposure of bacteria to sub-lethal doses (sAPDI). In this study, we aimed to evaluate the effect of sAPDI on Pseudomonas aeruginosa quorum sensing (QS) and c-di-GMP signaling which are important virulence factor regulatory systems.

Methods: Biofilm formation, pyoverdine, pyocyanin and protease production of P. Read More

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September 2019

Development of Staphylococcus aureus tolerance to antimicrobial photodynamic inactivation and antimicrobial blue light upon sub-lethal treatment.

Sci Rep 2019 07 1;9(1):9423. Epub 2019 Jul 1.

Laboratory of Molecular Diagnostics, Department of Biotechnology, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Gdansk, Poland.

Antimicrobial photodynamic inactivation (aPDI) and antimicrobial blue light (aBL) are considered low-risk treatments for the development of bacterial resistance and/or tolerance due to their multitargeted modes of action. In this study, we assessed the development of Staphylococcus aureus tolerance to these phototreatments. Reference S. Read More

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BODIPY-embedded electrospun materials in antimicrobial photodynamic inactivation.

Photochem Photobiol Sci 2019 Aug 31;18(8):1923-1932. Epub 2019 May 31.

Department of Chemistry, United States Air Force Academy, CO 80840, USA.

Drug-resistant pathogens, particularly those that result in hospital acquired infections (HAIs), have emerged as a critical priority for the World Health Organization. To address the need for self-disinfecting materials to counter the threat posed by the transmission of these pathogens from surfaces to new hosts, here we investigated if a cationic BODIPY photosensitizer, embedded via electrospinning into nylon and polyacrylonitrile (PAN) nanofibers, was capable of inactivating both bacteria and viruses via antimicrobial photodynamic inactivation (aPDI). Materials characterization, including fiber morphology and the degree of photosensitizer loading, was assessed by scanning electron microscopy (SEM), thermal gravimetric analysis (TGA), and UV-visible diffuse reflectance spectroscopy (UV-Vis DRS), and demonstrated that the materials were comprised of nanofibers (125-215 nm avg. Read More

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Antimicrobials Are a Photodynamic Inactivation Adjuvant for the Eradication of Extensively Drug-Resistant .

Front Microbiol 2019 13;10:229. Epub 2019 Feb 13.

Laboratory of Molecular Diagnostics, Department of Biotechnology, Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, Gdańsk, Poland.

The worldwide emergence of extensively drug resistant (XDR) has reduced the number of antimicrobials that exert high bactericidal activity against this pathogen. This is the reason why many scientists are focusing on investigations concerning novel non-antibiotic strategies such as antimicrobial photodynamic inactivation (aPDI) or the use of antimicrobial blue light (aBL). Therefore, the aim of the current study was to screen for antimicrobial synergies of routinely used antibiotics and phototherapies, including both aPDI involving exogenously administered photosensitizing molecules, namely, rose bengal, and aBL, involving excitation of endogenously produced photoactive compounds. Read More

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February 2019

Amphiphilic tetracationic porphyrins are exceptionally active antimicrobial photosensitizers: In vitro and in vivo studies with the free-base and Pd-chelate.

J Biophotonics 2019 08 24;12(8):e201800318. Epub 2019 Apr 24.

Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts.

Antimicrobial photodynamic inactivation (aPDI) employs the combination of nontoxic photosensitizing dyes and visible light to kill pathogenic microorganisms regardless of drug-resistance, and can be used to treat localized infections. A meso-substituted tetra-methylpyridinium porphyrin with one methyl group replaced by a C12 alkyl chain (FS111) and its Pd-derivative (FS111-Pd) were synthesized and tested as broad-spectrum antimicrobial photosensitizers when excited by blue light (5 or 10 J/cm ). Both compounds showed unprecedented activity, with the superior FS111-Pd giving 3 logs of killing at 1 nM, and eradication at 10 nM for Gram-positive methicillin-resistant Staphylococcus aureus. Read More

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Sub-lethal antimicrobial photodynamic inactivation: an in vitro study on quorum sensing-controlled gene expression of Pseudomonas aeruginosa biofilm formation.

Lasers Med Sci 2019 Aug 3;34(6):1159-1165. Epub 2019 Jan 3.

Department of Microbiology, School of Biology, College of Science, University of Tehran, Tehran, Iran.

During antimicrobial photodynamic inactivation (APDI) in the treatment of an infection, it is likely that microorganisms would be exposed to sub-lethal doses of APDI (sAPDI). Although sAPDI cannot kill microorganisms, it can significantly affect microbial virulence. In this study, we evaluated the effect of sAPDI using methylene blue (MB) on the expression of genes belonging to two quorum sensing (QS) operons (rhl and las systems) and two genes necessary for biofilm formation (pelF and pslA) under QS control in Pseudomonas aeruginosa. Read More

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Sodium nitrite potentiates antimicrobial photodynamic inactivation: possible involvement of peroxynitrate.

Photochem Photobiol Sci 2019 Feb;18(2):505-515

Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA, 02114, USA.

We have recently shown that a wide range of different inorganic salts can potentiate antimicrobial photodynamic inactivation (aPDI) and TiO2-mediated antimicrobial photocatalysis. Potentiation has been shown with azide, bromide, thiocyanate, selenocyanate, and most strongly, with iodide. Here we show that sodium nitrite can also potentiate broad-spectrum aPDI killing of Gram-positive MRSA and Gram-negative Escherichia coli bacteria. Read More

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February 2019

Antimicrobial Photodynamic Inactivation Mediated by Tetracyclines in Vitro and in Vivo: Photochemical Mechanisms and Potentiation by Potassium Iodide.

Sci Rep 2018 11 20;8(1):17130. Epub 2018 Nov 20.

Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA, USA.

Tetracyclines (including demeclocycline, DMCT, or doxycycline, DOTC) represent a class of dual-action antibacterial compounds, which can act as antibiotics in the dark, and also as photosensitizers under illumination with blue or UVA light. It is known that tetracyclines are taken up inside bacterial cells where they bind to ribosomes. In the present study, we investigated the photochemical mechanism: Type 1 (hydroxyl radicals); Type 2 (singlet oxygen); or Type 3 (oxygen independent). Read More

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November 2018