Journal
PHOTOCHEMICAL & PHOTOBIOLOGICAL SCIENCES
Volume 7, Issue 2, Pages 197-207Publisher
SPRINGERNATURE
DOI: 10.1039/b713374j
Keywords
-
Ask authors/readers for more resources
To establish the reaction mechanism of the high-quantum-yield bioluminescence in Cypridina (Vargula), we investigated the chemiluminescence of 6-aryl-2-methylimidazo[1,2-a] pyrazin-3(7H)-ones (1H) as Cypridina luciferin analogues in DMSO-1,1,3,3-tetramethylguanidine and in diglyme-acetate buffer. We found that the chemiluminescence of 1H with an electron-donating aryl group, such as a 4-(dimethylamino) phenyl, 3-indolyl or 3-(1-methyl) indolyl group, gave a high quantum yield (Phi(CL)) in diglymeacetate buffer. This indicates that the reaction mechanism producing this high Phi(CL) involves the chemiexcitation of a neutral dioxetanone intermediate possessing an electron-donating aryl group to the singlet excited state of neutral acetamidopyrazine (the light emitter). In addition, we investigated the. fluorescence of acetamidopyrazines and performed DFT calculations for neutral dioxetanones and the transition states (TS) of the dioxetanone's decomposition. The results made it clear that the electron-donating aryl group gives the TS and the singlet-excited acetamidopyrazine (S-1) a strong intramolecular charge transfer (ICT) character, and their similar ICT character leads to the ICT TS -> S-1 route in the charge transfer-induced luminescence (CTIL) mechanism for efficient chemiexcitation. The reaction mechanism of the chemiluminescence of 1H can explain the highly efficient chemiexcitation of Cypridina bioluminescence.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available