Photophysical and photosensitive properties of Elsinochrome A

In this paper, the photophysical and photosensitive properties of Elsinochrome A (EA), another member of perylenequinone photosensitizers derived via artificially biological synthesis, were stud- ied by taking hypocrellin A (HA) and hypocrellin B (HB) as the references. It was found that the quantum yield of singlet oxygen produced via the photosensi- tization of EA was 0.98 with HB (0.84) as a reference. Furthermore, the semiquinone anion could be pro- duced via photosensitization of EA in oxygen-free solution. Besides, taking advantage of nanosecond time-resolved spectral technique, the transient triplet absorption spectra and the lifetime of EA in cyclo- hexane were determined by the use of the ground- state depletion method.