Excited Triplet State Interactions with Molecular Oxygen: Influence of Charge Transfer on the Bimolecular Quenching Rate Constants and the Yields of Singlet Oxygen [O*2(1.DELTA.g)] for Substituted Naphthalenes in Various Solvents

1994 ◽  
Vol 98 (14) ◽  
pp. 3762-3769 ◽  
Author(s):  
F. Wilkinson ◽  
D. J. McGarvey ◽  
A. F. Olea
Keyword(s):  
Charge Transfer ◽  
Triplet State ◽  
Singlet Oxygen ◽  
Molecular Oxygen ◽  
Rate Constants ◽  
Excited Triplet State ◽  
Quenching Rate ◽  
Excited Triplet ◽  
Bimolecular Quenching

Determination of absolute rate constants for an excited triplet state

1978 ◽  
Vol 68 (1) ◽  
pp. 327 ◽  
Author(s):  
Willem R. Leenstra ◽  
Martin Gouterman ◽  
Alvin L. Kwiram
Keyword(s):  
Triplet State ◽  
Rate Constants ◽  
Excited Triplet State ◽  
Absolute Rate ◽  
Excited Triplet

PET-based bisBODIPY photosensitizers for highly efficient excited triplet state and singlet oxygen generation: tuning photosensitizing ability by dihedral angles

2017 ◽  
Vol 19 (36) ◽  
pp. 24792-24804 ◽  
Author(s):  
Xian-Fu Zhang ◽  
Xudong Yang ◽  
Baomin Xu
Keyword(s):  
Triplet State ◽  
Singlet Oxygen ◽  
Excited Triplet State ◽  
Dihedral Angles ◽  
Excited Triplet ◽  
Oxygen Generation ◽  
Singlet Oxygen Generation ◽  
Highly Efficient

PET-based excited triplet state and singlet oxygen photosensitizers: covalent BODIPY dimers.

PHOTOUREIDOMETHYLATION OF 9-CYANOPHENANTHRENE WITH TETRAMETHYLUREA INVOLVING THE CHARGE-TRANSFER PROCESS IN THE EXCITED TRIPLET STATE

1979 ◽  
Vol 8 (6) ◽  
pp. 613-616 ◽  
Author(s):  
Yuji Tsujimoto ◽  
Mitsunori Hayashi ◽  
Takuji Miyamoto ◽  
Yoshinobu Odaira ◽  
Yasuhiko Shirota
Keyword(s):  
Charge Transfer ◽  
Triplet State ◽  
Transfer Process ◽  
Excited Triplet State ◽  
Charge Transfer Process ◽  
Excited Triplet

Carotenoids, tocopherols and thiols as biological singlet molecular oxygen quenchers

1990 ◽  
Vol 18 (6) ◽  
pp. 1054-1056 ◽  
Author(s):  
PAOLO Di MASCIO ◽  
THOMAS P. A. DEVASAGAYAM ◽  
STEPHAN KAISER ◽  
HELMUT SIES
Keyword(s):  
Singlet Oxygen ◽  
Molecular Oxygen ◽  
Rate Constants ◽  
Protective Action ◽  
Biological Tissues ◽  
Oxygen Quenching ◽  
Quenching Rate ◽  
Singlet Molecular Oxygen ◽  
Singlet Oxygen Quenching ◽  
Β Carotene

Singlet molecular oxygen (1O2) has been shown to be generated in biological systems and is capable of damaging proteins, lipids and DNA. The ability of some biological antioxidants to quench 1O2 was studied by using singlet oxygen generated by the thermodissociation of the endoperoxide of 3,3′-(1,4-naphthylidene) dipropionate (NDPO2). The carotenoid lycopene was the most efficient 1O2 quencher (kq + kr = 31 × 109m-1s-1). Tocopherols and thiols were less effective. The singlet oxygen quenching ability decreased in the following order: lycopene, γ-carotene, astaxanthin, canthaxanthin, α-carotene, β-carotene, bixin, zeaxanthin, lutein, bilirubin, biliverdin, tocopherols and thiols. However, the compounds with low quenching rate constants occur at higher levels in biological tissues. Thus, carotenoids and tocopherols may contribute almost equally to the protection of tissues against the deleterious effects of 1O2. The quenching abilities of carotenoids and tocopherols were mainly due to physical quenching. In case of some thiols chemical quenching also plays a significant role. Carotenoids and tocopherols have been reported to exert a protective action against some types of cancer.

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