Center for Biomedical Engineering, Department of Chemical and Nuclear Engineering, 1 University of New Mexico, MSC01 1141, Albuquerque, New Mexico 87131-0001, USA.
Langmuir. 2011 Apr 19;27(8):4956-62. doi: 10.1021/la105018g. Epub 2011 Mar 15.
The light-induced antibacterial activity of symmetric and asymmetric oligophenylene ethynylenes (OPEs) was investigated against Gram-positive (Staphylococcus aureus and Staphylococcus epidermidis) and Gram-negative (Escherichia coli) bacteria. To understand the light-induced biocidal effect better, the transient absorption and triplet lifetime of OPEs were studied in methanol and water. A higher triplet lifetime was observed for OPE samples in water than in methanol. The magnitudes of the changes in optical density (ΔOD) of the S-OPE-n(H) series of symmetric oligomers are much higher than that of the asymmetric OPE-n series in water and are generally correlated with the singlet oxygen yield. It was found that the antibacterial activity against both Gram-positive and Gram-negative bacteria is size-, concentration-, and time-dependent. The light-induced antibacterial activity may result from the coordinated interactions of membrane disruption and interfacial or intracellular singlet oxygen generation, and the dominant factor is most likely the latter. The results obtained in this study will aid in the design of more efficient biocides in the future.
研究了对称和不对称寡聚苯乙炔（OPE）的光致抗菌活性对革兰氏阳性（金黄色葡萄球菌和表皮葡萄球菌）和革兰氏阴性（大肠杆菌）细菌的影响。为了更好地理解光诱导的杀菌效果，研究了 OPE 在甲醇和水中的瞬态吸收和三重态寿命。在水中观察到 OPE 样品的三重态寿命比在甲醇中长。在水中，S-OPE-n(H)系列对称寡聚物的光密度（ΔOD）变化幅度远高于不对称 OPE-n 系列，并且通常与单线态氧产率相关。结果发现，对革兰氏阳性和革兰氏阴性细菌的抗菌活性均与尺寸、浓度和时间有关。光诱导的抗菌活性可能来自于膜破坏和界面或细胞内单线态氧生成的协同相互作用，而主要因素很可能是后者。本研究的结果将有助于未来设计更有效的杀菌剂。
