title: Methylene Blue Doped Films of Wool Keratin with Antimicrobial Photodynamic Activity.
abstract: 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. As concerns the photodynamic effects on keratin, the ROS attack does not induce any significant photodegradation on the protein, even if a slight photo-oxidation of sulfonated amino acids occurs. Finally, the film with the highest MB concentration (400 μg per gram of keratin) displays a significant photobactericidal activity against Staphylococcus aureus with a bacterial reduction that increases by increasing the irradiation time. In particular, the irradiation of KFMB400 film incubated with S. aureus at a concentration of 10(8) cfu mL(-1) determined the 99.9% killing rate and the killing effect increased proportionally with irradiation time.
authors.affiliation: †Institute for Organic Synthesis and Photoreactivity, National Research Council, via P. Gobetti, 101, 40129 Bologna, Italy.
authors.forename: Annalisa
authors.initials: A
authors.lastname: Aluigi
authors.affiliation: †Institute for Organic Synthesis and Photoreactivity, National Research Council, via P. Gobetti, 101, 40129 Bologna, Italy.
authors.forename: Giovanna
authors.initials: G
authors.lastname: Sotgiu
authors.affiliation: †Institute for Organic Synthesis and Photoreactivity, National Research Council, via P. Gobetti, 101, 40129 Bologna, Italy.
authors.forename: Armida
authors.initials: A
authors.lastname: Torreggiani
authors.affiliation: †Institute for Organic Synthesis and Photoreactivity, National Research Council, via P. Gobetti, 101, 40129 Bologna, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Guerrini
authors.affiliation: ‡Department of Theoretical and Applied Sciences, University of Insubria, via J.H. Dunant 3, 21100 Varese, Italy.
authors.forename: Viviana T
authors.initials: VT
authors.lastname: Orlandi
authors.affiliation: §Institute for Microelectronics and Microsystems, National Research Council, via P. Gobetti, 101, 40129 Bologna, Italy.
authors.forename: Franco
authors.initials: F
authors.lastname: Corticelli
authors.affiliation: †Institute for Organic Synthesis and Photoreactivity, National Research Council, via P. Gobetti, 101, 40129 Bologna, Italy.
authors.forename: Greta
authors.initials: G
authors.lastname: Varchi
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000737:chemistry* / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D007633:Keratins / Q000737:chemistry*; D008027:Light; D008751:Methylene Blue / Q000737:chemistry* / Q000494:pharmacology; D010084:Oxidation-Reduction; D017382:Reactive Oxygen Species / Q000378:metabolism; D026082:Singlet Oxygen / Q000378:metabolism; D013211:Staphylococcus aureus / Q000187:drug effects; D014935:Wool / Q000378:metabolism*
chemical_list: D000890:Anti-Infective Agents; D017382:Reactive Oxygen Species; D026082:Singlet Oxygen; D007633:Keratins; D008751:Methylene Blue
keywords: antimicrobial photodynamic therapy; film; keratin; methylene blue; protein damage