Evaluation of singlet oxygen production of a novel chlorin photosensitizer

Photodynamic therapy (PDT) utilizes the combined action of photosensitizer, light, and molecular oxygen to generate reactive singlet oxygen (1O2) to treat various diseases. Photosensitizer is a key component in PDT and its singlet oxygen quantum yield determines the effectiveness of its photodynamic reaction. This study evaluated the singlet oxygen production of a novel water soluble chlorin photosensitizer (YLG-I) using a 1O2-specificfluorescence probe - Singlet Oxygen Sensor Green reagent (SOSG). The spectra and singlet oxygen luminescence in different solvents were evaluated using mTHPC as a reference. It was estimated and verified that the singlet oxygen quantum yield of the new photosensitizer YLG-I was at the same level of the potent chlorin sensitizer mTHPC. Preliminary evaluation suggested that YLG-I was a promising photosensitizer for PDT.