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A Photophysical Study of Purines and Theophylline by Using Laser‐Induced Optoacoustic Spectroscopy
Author(s) -
Murgida Daniel H.,
Bilmes Gabriel M.,
ErraBalsells Rosa
Publication year - 1996
Publication title -
photochemistry and photobiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.818
H-Index - 131
eISSN - 1751-1097
pISSN - 0031-8655
DOI - 10.1111/j.1751-1097.1996.tb01834.x
Subject(s) - theophylline , purine metabolism , spectroscopy , laser , chemistry , photochemistry , optics , physics , biochemistry , biology , pharmacology , quantum mechanics , enzyme
— The photophysics of purinic compounds (purine, 6‐meth‐ylpurine, 6‐aminopurine [adenine], 6‐chloropurine, 6‐methoxypurine) and theophylline in acetonitrile solution were studied by pulsed laser‐induced optoacoustic spectroscopy (LIOAS) exciting at 266 nm. The effect of O 2 , Xe and MnCl 2 on the photophysical behavior of these compounds was studied; as well, the formation quantum yield of purine and 6‐methylpurine triplet states were determined, with φ T = 0.88 ± 0.03 for both compounds. Multiphotonic and depletion processes were observed at high laser fluences. In order to explain this behavior, theoretical UV‐visible absorption electronic spectra from both the S 0 and S 1 state have been calculated for purines and theophylline by using the semiempirical PM3 and ZINDO/S methods.