Chemiluminescence from luminol solution after illumination of a 355 nm pulse laser.

Chemiluminescence (CL) on the time scale of microseconds to milliseconds from luminol solution after illumination of a 355 nm pulse laser is reported. It was found that the CL is the emission from 3-aminophthalate ion (AP*). In CL decay after the pulse laser illumination, a peak was observed from about 200 to 30 micros depending on the laser power and the luminol concentration. It seemed that there was a fast and slow decay process; their kinetics were greatly dependent on the laser power and the luminol concentration. Dissolved oxygen was involved in the CL and played the same role on the whole time scale of microseconds to milliseconds. Involvement of reactive oxygen species such as H(2)O(2), (1)O(2), O(2) (-) and OH in the CL was examined by adding their scavengers. Experimental results suggested that the possibility of involvement of H(2)O(2) and (1)O(2) in the CL was low. The CL in time periods less than 50 micros might be related to OH. The ()O(2) (-)-induced CL increased with time after 50 micros and became dominant on the time scale of milliseconds. The CL was considered to be caused by both the photoionization and type I reaction mechanisms.