Effect of preirradiation time of erythrosine + potassium iodide‐mediated photodynamic therapy on candidal inhibition and singlet oxygen formation
Year: 2025
Type: article
Abstract: We aimed to compare the anticandidal effect among different preirradiation times, measure singlet oxygen levels, and investigate the correlation between candidal reduction and singlet oxygen formation in erythrosine + KI photodynamic therapy. Candida albicans (ATCC10231) biofilms were treated with 100/200 μM erythrosine + 100 mM KI for 1, 3, or 5 min before light‐emitting diode (520 ± 10 nm, 250 mW/cm 2 , 20 J/cm 2 ) irradiation. Phosphate‐buffered saline, and nystatin were negative and positive controls, respectively. Candidal cells were quantified using a drop plate assay. Singlet oxygen was measured using a 9,10‐dimethylanthacene probe at 375/436 nm emission/excitation wavelengths. Median candidal counts and singlet oxygen formation were compared using Kruskal–Wallis with Dunn test. A p ‐value <0.05 was considered significant. Spearman's correlation was used to correlate candidal reduction and singlet oxygen formation. All preirradiation times for 200 μM erythrosine + 100 mM KI decreased candidal cells by 7.59 (IQR = 0.33) log 10 CFU/mL. At a 1‐min preirradiation, this group significantly generated higher singlet oxygen than the positive control ( p < 0.001). Singlet oxygen levels correlated mildly with candidal reduction in the lower erythrosine group but not the higher group, likely due to singlet oxygen saturation. A 1‐min preirradiation with 200 μM erythrosine + 100 mM KI generates singlet oxygen to inhibit C. albicans biofilms and shows potential for clinical oral candidiasis treatment.
Source: Photochemistry and Photobiology
DOI: 10.1111/php.70053
Institution: Khon Kaen University
Language: English
Subfield: Pulmonary and Respiratory Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
Award: G3366712923
OpenAlex ID: W4415760323