Department of Operative Dentistry and Periodontology, University Medical Center Regensburg, Franz-Josef-Strauss-Allee 11, 93053 Regensburg, Germany.
Department of Organic Chemistry, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg, Germany.
Free Radic Biol Med. 2013 Dec;65:477-487. doi: 10.1016/j.freeradbiomed.2013.07.031. Epub 2013 Jul 24.
Prevention and control of biofilm-growing microorganisms are serious problems in public health due to increasing resistances of some pathogens against antimicrobial drugs and the potential of these microorganisms to cause severe infections in patients. Therefore, alternative approaches that are capable of killing pathogens are needed to supplement standard treatment modalities. One alternative is the photodynamic inactivation of bacteria (PIB). The lethal effect of PIB is based on the principle that visible light activates a photosensitizer, leading to the formation of reactive oxygen species, e.g., singlet oxygen, which induces phototoxicity immediately during illumination. SAPYR is a new generation of photosensitizers. Based on a 7-perinaphthenone structure, it shows a singlet oxygen quantum yield ΦΔ of 99% and is water soluble and photostable. Moreover, it contains a positive charge for good adherence to cell walls of pathogens. In this study, the PIB properties of SAPYR were investigated against monospecies and polyspecies biofilms formed in vitro by oral key pathogens. SAPYR showed a dual mechanism of action against biofilms: (I) it disrupts the structure of the biofilm even without illumination; (II) when irradiated, it inactivates bacteria in a polymicrobial biofilm after one single treatment with an efficacy of ≥ 99.99%. These results encourage further investigation on the potential of PIB using SAPYR for the treatment of localized infectious diseases.
预防和控制生物膜生长微生物是公共卫生领域的严重问题，这是因为一些病原体对抗菌药物的耐药性不断增加，并且这些微生物有可能导致患者发生严重感染。因此，需要有能够杀死病原体的替代方法来补充标准治疗方法。一种替代方法是光动力细菌灭活（PIB）。PIB 的致死作用基于这样一个原理，即可见光激活光敏剂，导致活性氧（例如单线态氧）的形成，这在光照时立即引起光毒性。SAPYR 是新一代光敏剂。基于 7-萘满酮结构，它的单线态氧量子产率 ΦΔ 为 99%，并且水溶性和光稳定性好。此外，它还带有正电荷，有利于与病原体细胞壁的良好附着。在这项研究中，研究了 SAPYR 对口腔关键病原体体外形成的单物种和多物种生物膜的 PIB 特性。SAPYR 对生物膜具有双重作用机制：（I）即使没有光照，它也能破坏生物膜的结构；（II）当受到照射时，它可以在一次单一处理后使多微生物生物膜中的细菌失活，效力≥99.99%。这些结果鼓励进一步研究使用 SAPYR 进行光动力细菌灭活治疗局部感染性疾病的潜力。
