Maisch Tim
Antimicrobial PDT, Clinic and Polyclinic for Dermatology, Regensburg University Hospital, Germany, Franz-Josef-Strauss-Allee 11, 93053 Regensburg, Germany.
Mini Rev Med Chem. 2009 Jul;9(8):974-83. doi: 10.2174/138955709788681582.
Photodynamic activity of chemical compounds towards microorganisms was first published at the turn of 20th century and it is based on the concept that a chemical compound, known as the photosensitizer, is localized preferentially in the microorganism and subsequently activated by low doses of visible light of an appropriate wavelength to generate reactive oxygen species that are toxic to the target microorganisms. Processes, in which absorption of light by a photosensitizer induces chemical changes in another molecule, are defined as photosensitizing reactions. Since the middle of the last century, antibacterial photosensitizing reactions were forgotten because of the discovery and the beginning of the Golden Age of antibiotics. Certainly, in the last decades the worldwide rise in antibiotic resistance has driven research to the development of new anti-microbial strategies. Different classes of molecules including phenothiazine, porphyrines, phthalocyanines, and fullerenes have demonstrated antimicrobial efficacy against a broad spectrum of antibiotic resistant microorganisms upon illumination. Due to their extended pi-conjugated system these molecules absorb visible light, have a high triplet quantum yield and can generate reactive oxygen species upon illumination. This mini-review will focus on some major advances regarding physical and chemical properties of photosensitizers and light sources that appear to be suitable in the field of antimicrobial photodynamic therapy. Currently, topical application of a photosensitizer on infected tissues and subsequent illumination seems to be the most promising feature of antimicrobial photodynamic therapy, thereby not harming the surrounding tissue or disturbing the residual bacteria-flora of the tissue.
化合物对微生物的光动力活性最早于20世纪之交发表，其基于这样一个概念：一种被称为光敏剂的化合物优先定位于微生物中，随后被低剂量的适当波长可见光激活，以产生活性氧，这些活性氧对目标微生物有毒。光敏剂吸收光引发另一分子化学变化的过程被定义为光敏反应。自上世纪中叶以来，由于抗生素的发现和抗生素黄金时代的开始，抗菌光敏反应被遗忘了。当然，在过去几十年里，全球范围内抗生素耐药性的上升推动了新抗菌策略的研发。包括吩噻嗪、卟啉、酞菁和富勒烯在内的不同类分子在光照下已显示出对多种抗生素耐药微生物的抗菌效果。由于其扩展的π共轭体系，这些分子吸收可见光，具有高的三线态量子产率，并且在光照下能产生活性氧。本综述将聚焦于光敏剂和光源的物理化学性质方面的一些重大进展，这些进展似乎适用于抗菌光动力疗法领域。目前，在感染组织上局部应用光敏剂并随后进行光照似乎是抗菌光动力疗法最有前景的特点，从而不会损害周围组织或干扰组织中的残余菌群。
