Centre of Molecular and Macromolecular Studies, Polish Academy of Science, Sienkiewicza 112, 90-363 Lodz, Poland.
Department of Pharmaceutical Microbiology, Faculty of Pharmacy, Medical University of Gdańsk, gen. Hallera 107, 80-416 Gdańsk, Poland.
Int J Mol Sci. 2021 Dec 13;22(24):13373. doi: 10.3390/ijms222413373.
The high photodynamic effect of the Newman strain of the and of clinical strains of MRSA 12673 and 12519 are observed for new cationic light-activated phenosafranin polyhedral oligomeric silsesquioxane (POSS) conjugates in vitro. Killing of bacteria was achieved at low concentrations of silsesquioxanes (0.38 µM) after light irradiation (λ = 522 nm, 10.6 mW/cm) for 5 min. Water-soluble POSS-photosensitizers are synthesized by chemically coupling a phenosafranin dye (PSF) (3,7-diamino-5-phenylphenazine chloride) to an inorganic silsesquioxane cage activated by attachment of succinic anhydride rings. The chemical structure of conjugates is confirmed by H, C NMR, HRMS, IR, fluorescence spectroscopy and UV-VIS analyzes. The APDI and daunorubicin (DAU) synergy is investigated for POSSPSFDAU conjugates. Confocal microscopy experiments indicate a site of intracellular accumulation of the POSSPSF, whereas iBuPOSSPSF and POSSPSFDAU accumulate in the cell wall or cell membrane. Results from the TEM study show ruptured cells with leaking cytosolic mass and distorted cells of . Bacterial cells are eradicated by ROS produced upon irradiation of the covalent conjugates that can kill the bacteria by destruction of cellular membranes, intracellular proteins and DNA through the oxidative damage of bacteria.
新型阳离子光激活苯并呋喃多面体低聚倍半硅氧烷（POSS）缀合物在体外对 Newman 株 和临床分离的耐甲氧西林金黄色葡萄球菌（MRSA）12673 和 12519 菌株具有高光动力效应。在光照（λ=522nm，10.6mW/cm）5min 后，低浓度的硅烷（0.38µM）即可杀死细菌。通过化学偶联苯并呋喃染料（PSF）（3,7-二氨基-5-苯基吩嗪盐酸盐）到通过连接琥珀酸酐环激活的无机 POSS 笼中，合成了水溶性 POSS-光敏剂。通过 1H、13C NMR、高分辨率 MS、IR、荧光光谱和 UV-VIS 分析证实了缀合物的化学结构。研究了 POSSPSFDAU 缀合物的 APDI 和柔红霉素（DAU）协同作用。共聚焦显微镜实验表明，POSSPSF 在内质网中积累，而 iBuPOSSPSF 和 POSSPSFDAU 则在细胞壁或细胞膜中积累。TEM 研究结果表明，ROS 产生的细胞破裂，细胞质泄漏，细胞变形。通过破坏细胞膜、细胞内蛋白质和 DNA 以及通过氧化损伤杀死细菌，辐照共价缀合物可以杀死细菌。
