Department of Chemistry, University of York, Heslington York YO10 5DD, UK.
Molecules. 2020 Nov 12;25(22):5280. doi: 10.3390/molecules25225280.
Verteporfin, a free base benzoporphyrin derivative monoacid ring A, is a photosensitizing drug for photodynamic therapy (PDT) used in the treatment of the wet form of macular degeneration and activated by red light of 689 nm. Here, we present the first direct study of its photofragmentation channels in the gas phase, conducted using a laser interfaced mass spectrometer across a broad photoexcitation range from 250 to 790 nm. The photofragmentation channels are compared with the collision-induced dissociation (CID) products revealing similar dissociation pathways characterized by the loss of the carboxyl and ester groups. Complementary solution-phase photolysis experiments indicate that photobleaching occurs in verteporfin in acetonitrile; a notable conclusion, as photoinduced activity in Verteporfin was not thought to occur in homogenous solvent conditions. These results provide unique new information on the thermal break-down products and photoproducts of this light-triggered drug.
血卟啉单甲醚，一种游离碱基苯并卟啉衍生物单酸环 A，是一种光动力疗法（PDT）的光敏药物，用于治疗湿性黄斑变性，并通过 689nm 的红光激活。在这里，我们首次在气相中直接研究了它的光解通道，使用激光接口质谱仪在 250 至 790nm 的宽光激发范围内进行。将光解通道与碰撞诱导解离（CID）产物进行比较，揭示了相似的解离途径，其特征是失去羧基和酯基。补充的溶液相光解实验表明，在乙腈中的血卟啉发生光漂白；这是一个值得注意的结论，因为以前认为在均相溶剂条件下不会发生 Verteporfin 的光诱导活性。这些结果为这种光触发药物的热分解产物和光产物提供了独特的新信息。
