Silver ions and bacteria as promoters of UV-A photocatalysis

IF 4.1 3区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Photochemistry and Photobiology A-chemistry Pub Date : 2025-01-20 DOI:10.1016/j.jphotochem.2025.116269

Taito Iwabuchi , Taichi Tenkumo , Takayuki Mokudai , Toru Ogawa , Keiichi Sasaki , Nobuhiro Yoda

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引用次数: 0

Abstract

Aim

This study aimed to identify the ions used in disinfection treatments involving UV-A irradiation and to clarify the mechanism of free radical generation in three combinations of silver ions, Staphylococcus aureus, and UV-A irradiation, for applications in dental implants.

Methods

Free radicals were analyzed 1 or 4 min after combining various ions (Na, Mg, Al, Ca, Fe, Cu, Zn, Ag, Pt, or Au) with S. aureus, followed by UV-A irradiation. The mechanism of free radical generation from the UV-A irradiation of a mixture of Ag and S. aureus was examined using electron spin resonance (ESR), nuclear magnetic resonance (NMR), X-ray diffraction, and GSH/GSSG ELISA assays.

Results

Free radicals were generated from combinations of Na, Mg, Al, Ca, Zn, and Ag ions under UV-A irradiation in bacterial suspensions, with Ag producing the highest yield among all ions. Additionally, the mixture of Fe ions and bacterial suspension generated DMPO-SG. The combination of Ag ions and UV-A irradiation in bacterial suspensions resulted in the production of hydroxyl radicals. Free radicals were also generated from all cellular fractions upon UV-A irradiation in the presence of silver, with a higher yield observed in lipopolysaccharide and peptidoglycan. The combination of silver ions and UV-A irradiation oxidized GSH to GSSG, producing thiol radicals.

Conclusion

Silver ions in bacteria act as promoters of UV-A photocatalysis.

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来源期刊

Journal of Photochemistry and Photobiology A-chemistry 化学-物理化学

CiteScore

7.90

自引率

7.00%

发文量

580

审稿时长

48 days

期刊介绍： JPPA publishes the results of fundamental studies on all aspects of chemical phenomena induced by interactions between light and molecules/matter of all kinds. All systems capable of being described at the molecular or integrated multimolecular level are appropriate for the journal. This includes all molecular chemical species as well as biomolecular, supramolecular, polymer and other macromolecular systems, as well as solid state photochemistry. In addition, the journal publishes studies of semiconductor and other photoactive organic and inorganic materials, photocatalysis (organic, inorganic, supramolecular and superconductor). The scope includes condensed and gas phase photochemistry, as well as synchrotron radiation chemistry. A broad range of processes and techniques in photochemistry are covered such as light induced energy, electron and proton transfer; nonlinear photochemical behavior; mechanistic investigation of photochemical reactions and identification of the products of photochemical reactions; quantum yield determinations and measurements of rate constants for primary and secondary photochemical processes; steady-state and time-resolved emission, ultrafast spectroscopic methods, single molecule spectroscopy, time resolved X-ray diffraction, luminescence microscopy, and scattering spectroscopy applied to photochemistry. Papers in emerging and applied areas such as luminescent sensors, electroluminescence, solar energy conversion, atmospheric photochemistry, environmental remediation, and related photocatalytic chemistry are also welcome.