Medical University of Plovdiv, Plovdiv, Bulgaria.
Institute of Catalysis, Bulgarian Academy of Science, Sofia, Bulgaria.
Folia Med (Plovdiv). 2021 Jun 30;63(3):372-376. doi: 10.3897/folmed.63.e52102.
Antibacterial photodynamic therapy is a promising treatment modality in the anti-infective therapy of numerous oral diseases. It involves photo activation of a reactive substance (dye), thus releasing reactive oxygen species (ROS-radicals) which are highly destructive to the bacterial cell. However, thorough investigation of radical production properties of different dyes is not common in literature.
The aim of this study was to investigate and evaluate oxygen radical-producing potential of two commonly used photoactive dyes in the context of antibacterial photodynamic therapy.
The radical-producing properties of two commonly used dyes for photodynamic therapy in oral medicine, methylene blue and indocyanine green, irradiated under laser irradiation are investigated using electron paramagnetic resonance (EPR) spectroscopy. The detection of reactive oxygen species is performed with "spin-trapping" technique.
The selected photoactive dyes showed promising yields of reactive oxygen species (ROS) in aqueous solutions. The comparative analysis of the results deemed methylene blue as the more productive photoactive agent.
By employing the spin-trapping technique, this study indicates EPR-spectroscopy as a promising method of relative quantification of reactive oxygen species released by the photodynamic reaction in aqueous solutions.
抗菌光动力疗法是众多口腔疾病抗感染治疗中很有前途的治疗方式。它涉及到活性物质（染料）的光激活，从而释放出具有高度破坏性的活性氧物质（ROS-自由基）。然而，在文献中，对不同染料的自由基产生特性进行彻底研究并不常见。
本研究旨在调查和评估两种常用于口腔医学光动力疗法的光敏染料在抗菌光动力治疗中的产氧自由基的潜力。
使用电子顺磁共振（EPR）光谱法研究了两种常用于口腔医学光动力疗法的染料，亚甲蓝和吲哚菁绿，在激光照射下的自由基产生特性。使用“自旋捕获”技术检测活性氧物质。
所选的光活性染料在水溶液中表现出有希望的活性氧（ROS）生成量。对结果的比较分析认为亚甲蓝是更具生产力的光活性试剂。
通过采用自旋捕获技术，本研究表明 EPR 光谱学是一种有前途的相对定量方法，可用于测定水溶液中光动力反应释放的活性氧物质。
