Patterson M S, Madsen S J, Wilson B C
Hamilton Regional Cancer Centre, Ontario, Canada.
J Photochem Photobiol B. 1990 Apr 1;5(1):69-84. doi: 10.1016/1011-1344(90)85006-i.
Singlet oxygen (1O2) is thought to be the cytotoxic agent in photodynamic therapy (PDT) with current photosensitizers. Direct monitoring of 1O2 concentration in vivo would be a valuable tool in studying biological response. Attempts were made to measure 1O2 IR luminescence during PDT of cell suspensions and two murine tumour models using the photosensitizers Photofrin II and aluminium chlorosulphonated phthalocyanine. Instrumentation was virtually identical to that devised by Parker in the one positive report of in vivo luminescence detection in the literature. Despite the fact that our treatments caused cell killing and tissue necrosis, we were unable to observe 1O2 emission under any conditions. We attribute this negative result to a reduction in 1O2 lifetime in the cellular environment. Quantitative calibration of our system allowed us to estimate that the singlet oxygen lifetime in tissue is less than 0.5 microsecond. Some technical improvements are suggested which would improve detector performance and perhaps make such measurements feasible.
单线态氧（1O2）被认为是目前光敏剂在光动力疗法（PDT）中的细胞毒性剂。体内1O2浓度的直接监测将是研究生物反应的一个有价值的工具。人们尝试使用光敏剂二血卟啉醚和氯磺化铝酞菁在细胞悬液和两种小鼠肿瘤模型的光动力疗法期间测量1O2红外发光。仪器设备实际上与文献中关于体内发光检测的唯一一篇阳性报告中帕克设计的仪器相同。尽管我们的治疗导致了细胞杀伤和组织坏死，但我们在任何条件下都无法观察到1O2发射。我们将这个阴性结果归因于细胞环境中1O2寿命的缩短。我们系统的定量校准使我们能够估计组织中单线态氧的寿命小于0.5微秒。提出了一些技术改进措施，这些措施将提高探测器性能，也许会使此类测量变得可行。
