Department of Inorganic Chemistry, Faculty of Science, Charles University, Hlavova 2030, 128 43 Prague 2, Czech Republic.
Institute of Inorganic Chemistry of the Czech Academy of Sciences, 250 68, Husinec-Řež 1001, Czech Republic.
ACS Appl Mater Interfaces. 2020 Apr 22;12(16):18792-18802. doi: 10.1021/acsami.9b23104. Epub 2020 Apr 7.
A three-step postprocessing functionalization of pristine electrospun polystyrene nanofiber membranes was used for the preparation of nanostructured biotinylated materials with an externally bonded porphyrin photosensitizer. Subsequently, the material was able to strongly bind biologically active streptavidin derivatives while keeping its photosensitizing and antibacterial properties due to the generation of singlet oxygen under the exclusive control of visible light. The resulting multifunctional materials functionalized by a streptavidin-horseradish peroxidase conjugate as a model bioactive compound preserved its enzymatic activity even in the presence of a porphyrin photosensitizer with some quenching effect on the activity of the photosensitizer. Prolonged kinetics of both singlet oxygen luminescence and singlet oxygen-sensitized delayed fluorescence (SODF) were found after irradiation by visible light. The above results reflected less effective quenching of the porphyrin photosensitizer triplet state by ground state oxygen and indicated hindered oxygen transport (diffusion) due to surface functionalization. We found that SODF could be used as a valuable tool for optimizing photosensitizing efficiency as well as a tool for confirming surface functionalization. Full photosensitizing and enzyme activity could be achieved by a space separation of photosensitizers and enzyme/biomolecules in the nanofiber composites consisting of two layers. The upper layer contained a photosensitizer that generated antibacterial singlet oxygen upon irradiation by light, and the bottom layer retained enzymatic activity for biochemical reactions.
采用三步后处理功能化方法对原始静电纺丝聚苯乙烯纳米纤维膜进行功能化，制备了具有外部结合卟啉光敏剂的纳米结构生物素化材料。随后，由于在可见光的独家控制下产生单线态氧，该材料能够强烈结合生物活性链霉亲和素衍生物，同时保持其光敏和抗菌特性。用链霉亲和素-辣根过氧化物酶缀合物作为模型生物活性化合物对所得多功能材料进行功能化，即使在具有卟啉光敏剂的情况下，其酶活性也得以保留，而卟啉光敏剂对其活性具有一定的淬灭作用。在可见光照射后，发现单线态氧发光和单线态氧敏化延迟荧光（SODF）的动力学都延长了。上述结果反映出，由于表面功能化，三重态卟啉光敏剂的基态氧淬灭效率降低，并且表明氧的传输（扩散）受阻。我们发现，SODF 可作为优化光敏效率的有用工具，以及确认表面功能化的工具。由两层组成的纳米纤维复合材料中，通过将光敏剂和酶/生物分子空间分离，可以实现完全的光敏和酶活性。上层含有在光照下产生抗菌单线态氧的光敏剂，而底层则保留用于生化反应的酶活性。
