• Rafael R S Soares

      Articles written in Journal of Biosciences

    • Photodynamic effect of light-emitting diode light on cell growth inhibition induced by methylene blue

      Lílian S Peloi Rafael R S Soares Carlos E G Biondo Vagner R Souza Noboru Hioka Elza Kimura

      More Details Abstract Fulltext PDF

      The aim of this study was to propose the use of red light-emitting diode (LED) as an alternative light source for methylene blue (MB) photosensitizing effect in photodynamic therapy (PDT). Its effectiveness was tested against Staphylococcus aureus (ATCC 26923), Escherichia coli (ATCC 26922), Candida albicans (ATCC 90028) and Artemia salina. The maximum absorption of the LED lamps was at a wavelength of 663 nm, at intensities of 2, 4, 6 and 12 J.cm–2 for 10, 20, 30 and 60 min of exposure, respectively. Assays with and without LED exposure were carried out in plates containing MB at concentrations of 7 to 140.8 𝜇M for microorganisms and 13.35 to 668.5 𝜇M for microorganisms or microcrustaceans. The LED exposure induced more than 93.05%, 93.7% and 93.33% of growth inhibition for concentrations of 42.2 𝜇M for S. aureus (D-value=12.05 min) and 35.2 𝜇M for E. coli (D-value=11.51 min) and C. albicans (D-value=12.18 min), respectively after 20 min of exposure. LED exposure for 1 h increased the cytotoxic effect of MB against A. salina from 27% to 75%. Red LED is a promising light device for PDT that can effectively inhibit bacteria, yeast and microcrustacean growth.

  • Journal of Biosciences | News

    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

© 2017-2019 Indian Academy of Sciences, Bengaluru.