Heart lipoamide dehydrogenase, liver alcohol dehydrogenase and egg-white lysozyme are photo-oxidized in the presence of various dye sensitizers. The photodynamic process is preceded by the binding between the enzyme and the sensitizers. Among the commonly used dyes, halogenated xanthines and thiazine are effective sensitizers for the photo-inactivation of these three enzymes. Histidine residues...

1 Laboratory of Photodynamic Inactivation of Microorganisms, Department of Materials Science and Physics, University of Salzburg, Hellbrunnerstraße 34, 5020 Salzburg, Austria 2 Department of Dermatology, Eberhard Karls University, Liebermeisterstraße 25, 72076 Tuebingen, Germany 3Department of Internal Medicine I, Paracelsus Medical University and Salzburger Landeskliniken (SALK), Muellner Haup...

Photodynamic inactivation of virus was tested as a potential therapeutic tool for herpesvirus-induced keratitis, which is a leading cause of blindness and disability. Experimental keratitis produced in rabbits by infection with herpesvirus isolated from a human periorbital lesion was treated with proflavine and light. The herpetic keratitis could be rapidly resolved by the dye-light treatment, ...

Photodynamic inactivation (PDI) may be a very promising alternative method for the antimicrobial treatment of periodontitis. Several studies have demonstrated the sensitivity of subgingival flora to PDI using toluidine blue, methylene blue, and chlorin e6 derivatives. In the present study we report the activity of the Fotolon sensitizer, composed of chlorin e6 and polyvinylpyrrolidone (PVP), ag...

Studies were carried out on the photodynamic inactivation of Bacillus subtilis cells by He-Ne laser irradiation in presence of methylene blue and toluidine blue. Electron paramagnetic resonance (EPR) measurements show decrease in the cell membrane nuidity due to photodynamic damage of the lipophilic compartments. Study of cell damage in presence of sodium azide, 0 20 and glutathione as well as ...

We review the recent literature concerning the efficiency of antimicrobial photodynamic inactivation toward various microbial species in planktonic and biofilm cultures. The review is mainly focused on biofilm-growing microrganisms because this form of growth poses a threat to chronically infected or immunocompromised patients and is difficult to eradicate from medical devices. We discuss the b...

The photodynamic inactivation of coliphage T3 was studied over a wide range of concentrations of the dye proflavine. With 2 x 10(7) phage/ml, two modes of inactivation were observed. Between 0.25 and 12 to 13 mug/ml, inactivation was biphasic. There was an initial first-order inactivation (Rx1) which became temporally associated with an apparently multiorder process (Rx2) at higher light doses....

The excellent photoluminescent properties of graphene quantum dots (GQD) makes them suitable candidates for biomedical applications, but their cytotoxicity has not been extensively studied. Here we show that electrochemically produced GQD irradiated with blue light (470 nm, 1W) generate reactive oxygen species, including singlet oxygen, and kill U251 human glioma cells by causing oxidative stre...

Whereas the photodynamic therapy (PDT) of cancer has recently shown rapid clinical acceptance, photodynamic antimicrobial chemotherapy (PACT)--which predates the related cancer regimen--is not widely appreciated. Like PDT, PACT utilizes photosensitizers and visible or ultraviolet light in order to give a phototoxic response, normally via oxidative damage. Currently, the major use of PACT is in ...