Turk J Med Sci. 2018 Aug 16;48(4):873-879. doi: 10.3906/sag-1803-44.
BACKGROUND/AIM: This study was designed to evaluate the effect of antimicrobial photodynamic treatment (APDT) in a biofilm model using combinations of various dyes (rose bengal, riboflavin, and methylene blue) as photosensitizers and light sources (LED and UVA) against staphylococcal and candidal biofilms.
Sterile microtiter plates were used for the development and quantification of the biofilms. APDT was carried out using combinations of the light sources and dyes. The percentage of the growth inhibition was then calculated using a spectrophotometer. The broth media in the wells were aspirated, wells were stained with crystal violet, and optical density values were measured spectrophotometrically. SEM analysis of the impact of APDT on bacterial and fungal biofilms was also performed.
The experiments showed that the most efficacious combination was red LED + methylene blue against both staphylococcal and candidal biofilms. A marked inhibition (45.4%) was detected on both C. albicans and C. parapsilosis biofilms. Red LED + methylene blue was also effective on S. aureus and S. epidermidis biofilms. SEM images suggested that the number of adherent cells and biofilm mass were markedly reduced after APDT treatment.
Although the results of this study indicated the in vitro efficacy of APDT, it might also be a promising technique for the control of biofilm growth within intravenous catheters.
背景/目的：本研究旨在评估使用不同染料（孟加拉玫瑰红、核黄素和亚甲蓝）作为光敏剂和光源（LED 和 UVA）的组合在生物膜模型中对抗葡萄球菌和念珠菌生物膜的抗菌光动力治疗（APDT）的效果。
使用无菌微量滴定板来开发和量化生物膜。进行 APDT 时，使用光源和染料的组合。然后使用分光光度计计算生长抑制的百分比。从孔中吸出孔中的肉汤培养基，用结晶紫染色，并通过分光光度法测量光密度值。还对 APDT 对细菌和真菌生物膜的影响进行了 SEM 分析。
实验表明，最有效的组合是红色 LED +亚甲蓝，对葡萄球菌和念珠菌生物膜都有效。在白色念珠菌和近平滑念珠菌生物膜上均检测到明显的抑制作用（45.4%）。红色 LED +亚甲蓝对金黄色葡萄球菌和表皮葡萄球菌生物膜也有效。SEM 图像表明，APDT 处理后，附着细胞的数量和生物膜质量明显减少。
尽管这项研究的结果表明 APDT 的体外疗效，但它也可能是控制静脉内导管内生物膜生长的有前途的技术。
