title: An effective and potentially safe blood disinfection protocol using tetrapyrrolic photosensitizers.
abstract: Conventional disinfection techniques, considered safe for plasma, are usually associated with collateral damages on concentrated platelets and erythrocytes. Alternative methods are required and antimicrobial photodynamic therapy (aPDT) seems promising. In this study the effectiveness of two photosensitizers (PS), a porphyrin and a phthalocyanine, to disinfect blood products was evaluated.
  
  
  
  The cationic porphyrin was more effective in the photoinactivation of bacteria. Also, no significant osmotic stress was found for samples treated with PS at 5.0 µM in isotonic conditions after antimicrobial photodynamic therapy.
  
  
  
  Effective reduction of Gram-positive bacteria at 5.0 µM of PS provided promising indications toward its safe use to disinfect blood samples. For Gram-negative bacteria, lower PS concentrations, between 5.0 and 10 µM, must be tested.
authors.affiliation: Department of Biology & CESAM, University of Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: Lúcia
authors.initials: L
authors.lastname: Marciel
authors.affiliation: Department of Biology & CESAM, University of Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: Luís
authors.initials: L
authors.lastname: Teles
authors.affiliation: Department of Biology & CESAM, University of Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Moreira
authors.affiliation: Department of Biology & CESAM, University of Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: Mário
authors.initials: M
authors.lastname: Pacheco
authors.affiliation: Department of Chemistry & QOPNA, University of Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: Leandro Mo
authors.initials: LM
authors.lastname: Lourenço
authors.affiliation: Department of Chemistry & QOPNA, University of Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: Maria Gpms
authors.initials: MG
authors.lastname: Neves
authors.affiliation: Department of Chemistry & QOPNA, University of Aveiro, 3810-193 Aveiro, Portugal.|Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal.
authors.forename: João Pc
authors.initials: JP
authors.lastname: Tomé
authors.affiliation: Department of Chemistry & QOPNA, University of Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: Maria Af
authors.initials: MA
authors.lastname: Faustino
authors.affiliation: Department of Biology & CESAM, University of Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: Adelaide
authors.initials: A
authors.lastname: Almeida
mesh_terms: D001769:Blood / Q000382:microbiology*; D058731:Blood Safety; D004203:Disinfection; D004912:Erythrocytes / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects*; D006801:Humans; D007211:Indoles / Q000494:pharmacology; D054833:Isoindoles; D008027:Light; D017319:Photosensitizing Agents / Q000494:pharmacology*; D010949:Plasma / Q000382:microbiology; D011166:Porphyrins / Q000494:pharmacology; D013211:Staphylococcus aureus / Q000187:drug effects*
chemical_list: D007211:Indoles; D054833:Isoindoles; D017319:Photosensitizing Agents; D011166:Porphyrins; C013647:phthalocyanine
keywords: aPDT; antimicrobial photodynamic therapy; blood disinfection techniques; blood products; cationic phthalocyanines; cationic porphyrins