Singlet oxygen photodynamic action

In other cases fullerene antibacterial action takes place after photoirradiation of fulleropyrrolidinium salts. It is not yet clear if the photodynamic action implies the participation of superoxide and hydroxyl radicals (type I mechanism) or singlet oxygen (type II mechanism) but the efficacy is really interesting with the death of more than 99.9% of bacterial and fungal cells and a special selectivity for microbes over mammalian cells (Tegos et al., 2005). Also a sulfobutyl fullerene derivative is able to inhibit environmental bacteria after photoirradiation and it exerts its action on E. coli even if incorporated in coated polymer (Yu et al., 2005). 

Singlet-oxygen studies have being reported to such diverse areas as chemiluminescence [14], photocarcinogenity [15], ozonolysis [16], photodynamic action [17], peroxide decomposition [7], photosynthesis [14], air pollution [18], metallocatalyzed oxygenation reactions [19,20], synthetic applications [21], and polymer degradation [10]. 

Kalyanaraman, B., J.B. Ferx, F. Sieser, J.P. Thomas, and A.W. Girotti. Photodynamic Action of Merocyanine 540 on Artificial and Natural Cell Membranes Involvement of Singlet Molecular Oxygen. 

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