13 results match your criteria photobactericidal polymers

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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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Antibacterial photodynamic activity of photosensitizer-embedded alginate-pectin-carboxymethyl cellulose composite biopolymer films.

Lasers Med Sci 2021 Jun 7;36(4):763-772. Epub 2020 Aug 7.

Laser Biomedical Applications Division, Raja Ramanna Centre for Advanced Technology, Indore, 452013, Madhya Pradesh, India.

Antimicrobial photodynamic therapy (APDT) is a promising approach for treatment of wounds infected with antibiotic-resistant bacteria. In this approach, delivery of appropriate concentration of photosensitizer (PS) at the infected site is a critical step; it is therefore essential that PS need to be administered at the infected site in a suitable formulation. Here, we report preparation of PS-embedded composite biopolymer films and their photobactericidal properties against methicillin-resistant Staphylococcus aureus (MRSA) and biocompatibility. Read More

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Antibacterial Surfaces with Activity against Antimicrobial Resistant Bacterial Pathogens and Endospores.

ACS Infect Dis 2020 05 11;6(5):939-946. Epub 2020 Mar 11.

Division of Microbial Disease, UCL Eastman Dental Institute, University College London, 256 Gray's Inn Road, London WC1X 8LD, United Kingdom.

Hospital-acquired bacterial infections are a significant burden on healthcare systems worldwide causing an increased duration of hospital stays and prolonged patient suffering. We show that polyurethane containing crystal violet (CV) and 3-4 nm zinc oxide nanoparticles (ZnO NPs) possesses excellent bactericidal activity against hospital-acquired pathogens including multidrug resistant (), , methicillin-resistant (MRSA), and even highly resistant endospores of . Importantly, we used clinical isolates of bacterial strains, a protocol to mimic the environmental conditions of a real exposure in the healthcare setting, and low light intensity equivalent to that encountered in UK hospitals (∼500 lux). Read More

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Photoactivable Polymers Embedded with Cadmium-Free Quantum Dots and Crystal Violet: Efficient Bactericidal Activity against Clinical Strains of Antibiotic-Resistant Bacteria.

ACS Appl Mater Interfaces 2019 Apr 21;11(13):12367-12378. Epub 2019 Mar 21.

UCL Division of Surgery and Interventional Science , University College London , Charles Bell House, 43-45 Foley Street , London W1W 7TS , U.K.

The rising incidence of antibiotic-resistant infections from contaminated surfaces in hospitals or implanted medical devices has led to increasing interest in new antibacterial surfaces. Photoactivatable surfaces that can generate cytotoxic reactive oxygen species under exposure to ambient light is a promising approach to inactivation of surface-borne microorganisms. There is growing interest in the use of quantum dots (QDs) as light-harvesting agents for photobactericidal applications, but the cadmium in commonly used QDs will restrict clinical application. Read More

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Synthesis and photobactericidal properties of a neutral porphyrin grafted onto lignocellulosic fibers.

Mater Sci Eng C Mater Biol Appl 2016 May 12;62:61-7. Epub 2016 Jan 12.

Centre de Recherche sur les Matériaux Lignocellulosiques, Université du Québec à Trois-Rivières, 3351 boul. des Forges, C.P. 500, Trois-Rivières, QC G9A 5H7, Canada.

Photodynamic antimicrobial chemotherapy (PACT), as one of the promising alternative antimicrobial treatment, has received great attention in recent years. In this work, a new antimicrobial material has been elaborated by grafting a neutral porphyrin, the metallated 5-(4-azidophenyl)-10,15,20-triphenylporphyrin, onto lignocellulosic fibers by using the Copper (I)-Catalyzed Alkyne-Azide 1,3-dipolar Cycloaddition (CuAAC) reaction. The cross-linked porphyrin-Kraft pulp material was characterized by infrared and by XPS spectroscopy analyses, which proved the covalent linkage between the porphyrin and propargylated Kraft pulp fibers. Read More

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Lethal photosensitisation of Staphylococcus aureus and Escherichia coli using crystal violet and zinc oxide-encapsulated polyurethane.

J Mater Chem B 2015 Aug 20;3(31):6490-6500. Epub 2015 Jul 20.

Materials Chemistry Research Centre, Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK.

Crystal violet and zinc oxide nanoparticles (CVZnO) were incorporated into medical grade polyurethane polymers by a two-step dipping procedure to prepare novel bactericidal surfaces. The photobactericidal activity of CVZnO polyurethane samples was tested against the Gram-positive bacterium, Staphylococcus aureus and the Gram-negative bacterium, Escherichia coli. Exposure of the polymer samples to white light induced the lethal photosensitisation of both S. Read More

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Methylene Blue Doped Films of Wool Keratin with Antimicrobial Photodynamic Activity.

ACS Appl Mater Interfaces 2015 Aug 31;7(31):17416-24. Epub 2015 Jul 31.

†Institute for Organic Synthesis and Photoreactivity, National Research Council, via P. Gobetti, 101, 40129 Bologna, Italy.

In this work, keratin films doped with different amounts of methylene blue (MB) were developed in order to prepare new biodegradable and biocompatible materials for tissue engineering and wound healing, able to exert antimicrobial photodynamic activity upon irradiation with visible light. Preliminary results indicated that the swelling ratio, as well as the MB release, increases by increasing the pH. Moreover, the generation of reactive oxygen species (ROS) and singlet oxygen can be easily triggered and controlled by a fine-tuning of the irradiation time and MB concentration in the films. Read More

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Porphyrin-cellulose nanocrystals: a photobactericidal material that exhibits broad spectrum antimicrobial activity.

Photochem Photobiol 2012 May-Jun;88(3):527-36. Epub 2012 Mar 28.

Department of Chemistry, North Carolina State University, Raleigh, NC, USA.

Towards our overall objectives of developing potent antimicrobial materials to combat the escalating threat to human health posed by the transmission of surface-adhering pathogenic bacteria, we have investigated the photobactericidal activity of cellulose nanocrystals that have been modified with a porphyrin-derived photosensitizer (PS). The ability of these previously synthesized porphyrin-cellulose-nanocrystals (CNC-Por (1)) to mediate bacterial photodynamic inactivation was investigated as a function of bacterial strain, incubation time and illumination time. Despite forming an insoluble suspension, CNC-Por (1) showed excellent efficacy toward the photodynamic inactivation of Acinetobacter baumannii, multidrug-resistant Acinetobacter baumannii (MDRAB) and methicillin-resistant Staphylococcus aureus (MRSA), with the best results achieving 5-6 log units reduction in colony forming units (CFUs) upon illumination with visible light (400-700 nm; 118 J cm(-2)). Read More

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Photobactericidal porphyrin-cellulose nanocrystals: synthesis, characterization, and antimicrobial properties.

Biomacromolecules 2011 Oct 16;12(10):3528-39. Epub 2011 Sep 16.

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

Adherence and survival of pathogenic bacteria on surfaces leading to concomitant transmission to new hosts significantly contributes to the proliferation of pathogens, which in turn considerably increases the threat to human health, particularly by antibiotic-resistant bacteria. Consequently, more research into effective surface disinfection and alternative materials (fabrics, plastics, or coatings) with antimicrobial and other bioactive characteristics is desirable. This report describes the synthesis and characterization of cellulose nanocrystals that were surface-modified with a cationic porphyrin. Read More

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October 2011

Eradication of bacteria in suspension and biofilms using methylene blue-loaded dynamic nanoplatforms.

Antimicrob Agents Chemother 2009 Jul 4;53(7):3042-8. Epub 2009 May 4.

University of Michigan, Department of Environmental Health Sciences, 109 Observatory St., Ann Arbor, MI 48109, USA.

The bacterial killing efficiency of a dynamic nanoplatform (DNP) was evaluated. The polyacrylamide (PAA) hydrogel matrix of the DNP was loaded with methylene blue (MB) and was previously applied successfully to killing rat C6 glioma tumor cells in culture. This series of experiments is aimed at determining the suitability of this nanoplatform for elimination of bacterial infections. Read More

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Photobactericidal plastic films based on cellulose esterified by chloroacetate and a cationic porphyrin.

Bioorg Med Chem 2008 Dec 8;16(23):10091-7. Epub 2008 Oct 8.

Université de Limoges, Laboratoire de Chimie des Substances Naturelles, 123, Avenue Albert Thomas, 87060 Limoges cedex, France.

The synthesis and characterisation of pyridinium porphyrinic chloroacetyl cellulose ester chlorides, where photosensitizing agents are covalently bounded to the polymeric chain, is presented in this paper. First, cellulose was homogenously converted into chloroacetate cellulose ester in DMAc/LiCl solvent by using chloroacetyl chloride. The complete substitution of cellulose was achieved using 7equiv of chloroacetyl chloride for a 2h reaction at room temperature. Read More

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December 2008

Effect of Ca+ on the photobactericidal efficacy of methylene blue and toluidine blue against gram-negative bacteria and the dye affinity for lipopolysaccharides.

Lasers Surg Med 2006 Dec;38(10):946-54

Advanced Photodynamic Technologies, Inc., Minneapolis, Minnesota 55414, USA.

Background And Objectives: Methylene blue (MB) and toluidine blue (TB) form metachromatic complexes with lipopolysaccharides (LPS). The greater photobactericidal efficacy of TB may be explained by its affinity for LPS. This study aims to elucidate the difference in photobactericidal efficacies between the dyes using Ca(2+) as a competitor for dye-binding sites on the bacterial outer membrane. Read More

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December 2006

New photoantimicrobial films composed of porphyrinated lipophilic cellulose esters.

Bioorg Med Chem Lett 2006 Mar 11;16(6):1651-5. Epub 2006 Jan 11.

Université de Limoges, Laboratoire de Chimie des Substances Naturelles, 123 Avenue Albert Thomas, 87060 Limoges cedex, France.

Porphyrinated cellulose laurate esters have been prepared in homogeneous DMA/LiCl medium by "one-pot, two-step" reactions starting from cellulose, protoporphyrin IX, and lauric acid and using a TsCl/Pyridine system. The plastic films obtained after casting were shown to display photobactericidal activity against Gram positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. This new photobactericidal polymer has potential for industrial, medical, or household applications. Read More

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