A novel technique of antimicrobial photodynamic therapy - aPDT using 1,9-dimethyl-methylene blue zinc chloride double salt-DMMB and polarized light on Staphylococcus aureus.

Autor: Santos DA; Center of Health Science, Federal University of the Reconcavo Bahiano, Carlos Amaral Ave, 1015 - Cajueiro, Santo Antônio de Jesus, BA CEP: 44.574-490, Brazil; Center of Biophotonics, Federal University of Bahia, 62, Araujo Pinho Ave, Canela, Salvador, BA 40110-150, Brazil., Crugeira PJL; Center of Biophotonics, Federal University of Bahia, 62, Araujo Pinho Ave, Canela, Salvador, BA 40110-150, Brazil; Laboratory of Biotechnology and Ecology of Micro-organisms, Institute of Health Science, Federal University of Bahia, Reitor Miguel Calmon Ave, S/N, Salvador, BA CEP:40110-100, Brazil., Nunes IPF; Center of Biophotonics, Federal University of Bahia, 62, Araujo Pinho Ave, Canela, Salvador, BA 40110-150, Brazil., de Almeida PF; Center of Biophotonics, Federal University of Bahia, 62, Araujo Pinho Ave, Canela, Salvador, BA 40110-150, Brazil; Laboratory of Biotechnology and Ecology of Micro-organisms, Institute of Health Science, Federal University of Bahia, Reitor Miguel Calmon Ave, S/N, Salvador, BA CEP:40110-100, Brazil. Electronic address: pfa@ufba.br., Pinheiro ALB; Center of Biophotonics, Federal University of Bahia, 62, Araujo Pinho Ave, Canela, Salvador, BA 40110-150, Brazil; Laboratory of Biotechnology and Ecology of Micro-organisms, Institute of Health Science, Federal University of Bahia, Reitor Miguel Calmon Ave, S/N, Salvador, BA CEP:40110-100, Brazil; National Institute Basic Optics and Applied to Life Science, 400, Trabalhador São-Carlense Ave, Parque Arnold Schimidt, São Carlos, SP CEP:13566-590, Brazil; Brasil University Scientific and Techological Institute, 235, Carolina Fonseca St, Itaquera, São Paulo, SP CEP:08230-030, Brazil. Electronic address: albp@ufba.br.
Jazyk: angličtina
Zdroj: Journal of photochemistry and photobiology. B, Biology [J Photochem Photobiol B] 2019 Nov; Vol. 200, pp. 111646. Date of Electronic Publication: 2019 Oct 13.
DOI: 10.1016/j.jphotobiol.2019.111646
Abstrakt: Antimicrobial Photodynamic Therapy (aPDT) is an alternative to conventional treatments of local infections such as the use of antibiotics, which may lead to the development of resistance. aPDT besides requiring the use of a photosensitiser also needs a light source do be carried out. In the search for efficient and low-cost procedure the use of multispectral polarized light (λ400-2000 nm) emerges as a possibility for the execution of aPDT. The use of a highly effective photosensitizer is also of great importance. 1,9-Dimethyl-Methylene Blue Zinc Chloride Double Salt - DMMB is a potent phenothiazine derivative that presents high photodynamic action due to its high lipophilicity as well as a greater quantum yield of Singlet oxygen and phototoxicity when compared to other Photosensitizers. The aim of this study was to assess, In Vitro, the efficacy of aPDT on Staphylococcus aureus (ATCC 25923) using different concentrations of DMMB associated to a Polarized light source (Bioptron®, 40 mW, ᴓ = 15.8 cm 2 ) using different energy densities. Based on the IC 50 , 150 and 300 ng/mL of DMMB concentrations were chosen for this study. Twelve experimental groups were used: (Control, PLs, PSs and aPDTs). Serial dilutions (up to 10 -8 ) of the bacterial inoculum were used and the DMMB was added using the two previously determined concentrations. After 5 min of preincubation the dilutions of the inoculum were illuminated by the polarized light source. Subsequently, 100 μL of each dilution, in triplicate, were inoculated into Petri dishes containing TSA medium and incubated in a bacteriological oven at 37 °C for 24-h and quantification of UFCs was done. The results showed significant exponential reduction (p < .0001) of 99.93% (150 ng/mL + LP 10 J/cm 2 ) and 99.97% (300 ng/mL + LP 5 J/cm 2 ) the CFU counts in comparison to non-illuminated control. The results of this study allow to conclude that aPDT carried out with 1,9-Dimethyl-Methylene Blue Zinc Chloride Double Salt-DMMB and a PL souce was efficacious on the reduction (99.97%), in vitro, of the bacterial counts of S. aureus.
(Copyright © 2019 Elsevier B.V. All rights reserved.)
Databáze: MEDLINE
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