The effect of iodide and temperature on enhancing antibacterial properties of nanoparticles with an encapsulated photosensitizer

0510021 - ÚFCH JH 2020 RIV NL eng J - Článek v odborném periodiku
Kubát, Pavel - Henke, P. - Mosinger, Jiří
The effect of iodide and temperature on enhancing antibacterial properties of nanoparticles with an encapsulated photosensitizer.
Colloids and Surfaces B-Biointerfaces. Roč. 176, APR 2019 (2019), s. 334-340. ISSN 0927-7765. E-ISSN 1873-4367
Grant CEP: GA ČR(CZ) GA16-15020S
Institucionální podpora: RVO:61388955 ; RVO:61388980
Klíčová slova: antimicrobial photodynamic inactivation * nanofiber materials * photophysical properties * escherichia-coli * oxygen diffusion * aggregation * polystyrene * surfaces * Nanoparticles * Potassium iodide
Obor OECD: Physical chemistry; Inorganic and nuclear chemistry (UACH-T)
Impakt faktor: 4.389, rok: 2019
Způsob publikování: Omezený přístup

Aqueous dispersions of sulfonated polystyrene nanoparticles (average diameter: 30 +/- 14 nm) with encapsulated 5,10,15,20-tetraphenylporphyrin (TPP) are promising candidates for antibacterial treatments due to the photogeneration of cytotoxic singlet oxygen species O-2((1)Delta(g)) under physiological conditions using visible light. The antibacterial effect on gram-negative Escherichia coli was significantly enhanced after the addition of nontoxic potassium iodide (0.001-0.01 M) because photogenerated O-2((1)Delta(g)) oxidized iodide to I-2/I-3(-), which is another antibacterial species. The improved antibacterial properties were predicted using luminescence measurements of O-2((1)Delta(g)), transient absorption of TPP triplets and singlet oxygen-sensitized delayed fluorescence (SODF). In contrast to a solution of free photosensitizers, the aqueous dispersion of photoactive nanoparticles did not exhibit any quenching of the excited states after the addition of iodide or any tendency toward aggregation and/or I-3(-)-induced photo-aggregation. We also observed a decrease in the lifetime of O-2((1)Delta(g)) and a significant increase in SODF intensity at higher temperatures, due to the increased oxygen diffusion coefficient in nanoparticles and aqueous surroundings. This effect corresponds with the significantly stronger antibacterial effect of nano particles at physiological temperature (37 degrees C) in comparison with that at room temperature (25 degrees C).
Trvalý link: http://hdl.handle.net/11104/0300594