title: Polymer-immobilized photosensitizers for continuous eradication of bacteria.
abstract: The photosensitizers Rose Bengal (RB) and methylene blue (MB), when immobilized in polystyrene, were found to exhibit high antibacterial activity in a continuous regime. The photosensitizers were immobilized by dissolution in chloroform, together with polystyrene, with further evaporation of the solvent, yielding thin polymeric films. Shallow reservoirs, bottom-covered with these films, were used for constructing continuous-flow photoreactors for the eradication of Gram-positive Staphylococcus aureus, Gram-negative Escherichia coli and wastewater bacteria under illumination with visible white light using a luminescent lamp at a 1.8 mW·cm⁻² fluence rate. The bacterial concentration decreased by two to five orders of magnitude in separate reactors with either immobilized RB or MB, as well as in three reactors connected in series, which contained one of the photosensitizers. Bacterial eradication reached more than five orders of magnitude in two reactors connected in series, where the first reactor contained immobilized RB and the second contained immobilized MB.
authors.affiliation: Department of Chemical Engineering, Biotechnology and Materials, Ariel University, Ariel 40700, Israel. anton_valkov@walla.com.
authors.forename: Anton
authors.initials: A
authors.lastname: Valkov
authors.affiliation: Department of Chemical Engineering, Biotechnology and Materials, Ariel University, Ariel 40700, Israel. fainan@ariel.ac.il.
authors.forename: Faina
authors.initials: F
authors.lastname: Nakonechny
authors.affiliation: Department of Chemical Engineering, Biotechnology and Materials, Ariel University, Ariel 40700, Israel. marinan@ariel.ac.il.
authors.forename: Marina
authors.initials: M
authors.lastname: Nisnevitch
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D002725:Chloroform / Q000737:chemistry; D004926:Escherichia coli / Q000187:drug effects*; D008751:Methylene Blue / Q000737:chemistry / Q000494:pharmacology*; D017319:Photosensitizing Agents / Q000737:chemistry / Q000494:pharmacology*; D011137:Polystyrenes / Q000737:chemistry*; D012395:Rose Bengal / Q000737:chemistry / Q000494:pharmacology*; D012498:Sanitary Engineering / Q000379:methods; D013211:Staphylococcus aureus / Q000187:drug effects*
chemical_list: D000900:Anti-Bacterial Agents; D017319:Photosensitizing Agents; D011137:Polystyrenes; D012395:Rose Bengal; D002725:Chloroform; D008751:Methylene Blue