Chemiluminescence Arising from the Action of 1Δg-Molecular Oxygen on Chlorophyll-a

1973 ◽  
Vol 28 (5-6) ◽  
pp. 302-309 ◽  
Author(s):  
Hartmut Fuhr ◽  
Joachim Stauff
Keyword(s):  
Computer Simulation ◽  
Singlet Oxygen ◽  
Molecular Oxygen ◽  
Chlorophyll A ◽  
Microwave Discharge ◽  
Singlet State ◽  
Excited Species

Singlet oxygen (1Δg) was generated by a microwave discharge and bubbled through a solution of chlorophyll-a in dibutylphtalate at approximately 10-20 torr. It not only excited the dye to its first singlet state but also produced oxidized species which generated a very long lasting weak chemiluminescence. From quenching experiments for the generation of the excited species could computer simulation.

Optical Properties of Photodynamic Therapy Drugs in Different Environments: The Paradigmatic Case of Temoporfin

2020 ◽  
Author(s):  
busenur Aslanoglu ◽  
Ilya Yakavets ◽  
Vladimir Zorin ◽  
Henri-Pierre Lassalle ◽  
Francesca Ingrosso ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Optical Properties ◽  
Photodynamic Therapy ◽  
Minimally Invasive ◽  
Visible Light ◽  
Cancer Treatment ◽  
Singlet Oxygen ◽  
Tumor Cells ◽  
Molecular Oxygen ◽  
Computational Tools

Computational tools have been used to study the photophysical and photochemical features of photosensitizers in photodynamic therapy (PDT) –a minimally invasive, less aggressive alternative for cancer treatment. PDT is mainly based by the activation of molecular oxygen through the action of a photoexcited sensitizer (photosensitizer). Temoporfin, widely known as mTHPC, is a second-generation photosensitizer, which produces the cytotoxic singlet oxygen when irradiated with visible light and hence destroys tumor cells. However, the bioavailability of the mostly hydrophobic photosensitizer, and hence its incorporation into the cells, is fundamental to achieve the desired effect on malignant tissues by PDT. In this study, we focus on the optical properties of the temoporfin chromophore in different environments –in <i>vacuo</i>, in solution, encapsulated in drug delivery agents, namely cyclodextrin, and interacting with a lipid bilayer.

Polydiene Oxidations with Singlet Oxygen

1972 ◽  
Vol 45 (2) ◽  
pp. 423-436 ◽  
Author(s):  
M. L. Kaplan ◽  
P. G. Kelleher
Keyword(s):  
Singlet Oxygen ◽  
Gas Phase ◽  
Molecular Oxygen ◽  
Ground State ◽  
Homogeneous Solution ◽  
Surface Oxidation ◽  
Electrodeless Discharge ◽  
Photosensitized Oxidation

Abstract Excited molecular oxygen in its singlet delta (1Δg) state can be made chemically in homogeneous solution and in the gas-phase by the electrodeless discharge of ground state oxygen. Both techniques have been used to perform oxidations of polydiene systems. Solutions of high cis, trans, and vinyl polybutadienes have been treated with singlet oxygen produced in situ. Only the high cis and high trans were oxidized, apparently by different mechanisms. Squalene, a model for polyisoprene, has been oxidized in solution and the initially formed hydroperoxides reduced and analyzed and found identical to the product from a photosensitized oxidation. Cis-polybutadiene films were treated with gas-phase singlet oxygen and the extent of surface oxidation was monitored spectroscopically and chemically.

Sign in / Sign up

Export Citation Format

Share Document