Physico-chemical modeling of the role of free radicals in photodynamic therapy. II. Interactions of ground state sensitizers with free radicals studied by chemiluminescence spectrometry.
Chemiluminescence (CL) studies of the interaction between ground state hematoporphyrin photosensitizer (Hp) and peroxy radicals generated by the initiated oxidation of ethylbenzene at 60-80 degrees C revealed, that Hp is a singlet-singlet acceptor similarly to 9,10-diphenylanthracene. Furthermore, the fast decrease in the CL signal in the presence of Hp indicated that its consumption also took place due to chemical transformation, presumably by the attack of peroxy radicals on Hp. The rate constant of this attack has been calculated and it supports the view that such interaction can lead to an essential contribution to the bleaching processes in vivo.
Vasvári
G
G
Central Research Institute for Chemistry of the Hungarian Academy of Sciences, Budapest.
Elzemzam
S
S
Gál
D
D
D001555:Benzene Derivatives; D005609:Free Radicals; D006415:Hematoporphyrins / Q000737:chemistry*; D008163:Luminescent Measurements; D008962:Models, Theoretical; D010084:Oxidation-Reduction; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000737:chemistry*; D013053:Spectrophotometry / Q000379:methods
D001555:Benzene Derivatives; D005609:Free Radicals; D006415:Hematoporphyrins; D017319:Photosensitizing Agents; C004912:ethylbenzene