Detection Techniques For Time-and Spatially-resolved Singlet Oxygen Luminescence

Singlet oxygen (1O2) is widely considered to be the major cytotoxic species generated during Type-Ⅱ photochemical reaction of photodynamic therapy (PDT), and its production is crucial for the treatment outcome of PDT. Most recently, direct measurement of O2luminescence at1270nm has received considerable attention with the advances of near-infrared detector and photon counting techniques. In this study, based on the analysis of the existing photon counting techniques, a time-resolved1O2luminescence detection system using the MSA-300photon counters is proposed to measure1O2luminescence, and the derived lifetimes of triplet state and1O2during photosensitization were obtained. Furthermore, a spatially-resolved1O2luminescence imaging system was also developed to achieve spatially-resolved measurement of1O2luminescence during photosensitization. The obtained results indicate that both the time-resolved and spatially-resolved1O2luminescence have the potential application for the studies of1O2dosimetry during PDT treatments.