N.N. Semenov Institute of Chemical Physics, Department of Polymers and Composites, 4 Kosygin St., 119991, Moscow, Russia.
Institute for Regenerative Medicine, I. M. Sechenov First Moscow State Medical University, 8 Trubetskaya St., Moscow, 119991, Russia.
Sci Rep. 2018 May 23;8(1):8042. doi: 10.1038/s41598-018-26458-6.
By the example of a model process of tryptophan photooxidation in the aqueous medium in the presence of a three-component photosensitizing complex (porphyrin photosensitizer-polyvinylpyrrolidone- chitosan, PPS-PVP-CT) in the temperature range of 20-40 °С, we have demonstrated a possibility of modification of such a process by selecting different molar ratios of the components in the reaction mixture. The actual objective of this selection is the formation of a certain PPS-PVP-CT composition in which PVP macromolecules would coordinate with PPS molecules and at the same time practically block the complex binding of PPS molecules with chitosan macromolecules. Such blocking allows utilization of the bactericidal properties of chitosan to a greater extent, since chitosan is known to depress the PPS photosensitizing activity in PPS-PVP-CT complexes when using those in photodynamic therapy (PDT). The optimal composition of photosensitizing complexes appears to be dependent on the temperature at which the PDT sessions are performed. We have analyzed the correlations of the effective rate constants of tryptophan photooxidation with the photophysical characteristics of the formed complexes.
通过在 20-40°C 的温度范围内，在含有三组分光敏剂复合物（卟啉光敏剂-聚乙烯吡咯烷酮-壳聚糖，PPS-PVP-CT）的水介质中色氨酸光氧化的模型过程为例，我们已经证明了通过选择反应混合物中不同的摩尔比来改变该过程的可能性。这种选择的实际目的是形成一定的 PPS-PVP-CT 组成，其中 PVP 大分子与 PPS 分子配位，同时实际上阻止 PPS 分子与壳聚糖大分子的复合物结合。这种阻断允许更大程度地利用壳聚糖的杀菌特性，因为众所周知，在光动力疗法（PDT）中使用 PPS-PVP-CT 复合物时，壳聚糖会抑制 PPS 的光敏活性。光敏复合物的最佳组成似乎取决于进行 PDT 疗程的温度。我们分析了色氨酸光氧化的有效速率常数与形成的复合物的光物理特性之间的相关性。
