Rapid Communication: Direct Optical Detection of Singlet Oxygen from a Single Cell ¶

Singlet oxygen has been detected in single nerve cells by its weak 1270 nm phosphorescence (a 1 Dg ! X 3 S 2 ) upon irradiation of a photosensitizer incorporated in the cell. Thus, one can now consider the application of direct optical imaging techniques to mechanistic studies of singlet oxygen at the single-cell level.