Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
4754587 | Journal of Photochemistry and Photobiology B: Biology | 2017 | 10 Pages |
â¢C-dots were synthesized and characterized.â¢C-dots ceased colony formation of S. aureus.â¢The bactericidal effect of C-dots was accelerated by 808-nm light irradiation.â¢The mechanism of bactericidal effect of C-dots/light was explored.
Suspensions of Staphylococcus aureus (S. aureus) and methicillin-resistant S. aureus (MRSA) were irradiated with a 808-nm diode laser in the presence of different concentrations of carbon dots (C-dots). The effects of laser irradiation and C-dots on the bactericidal activity were separately investigated. The results indicated that without laser irradiation, C-dots caused to a significant cease in the colony formation of both wild and methicillin-resistance types of S. aureus in a concentration-dependent manner. On the other hand, the bactericidal effect of C-dots was accelerated upon laser irradiation. Mechanistic studies revealed that formation of reactive oxygen species and protein leakage, which occurred in the presence of C-dots, were greatly accelerated by laser irradiation. Moreover, field emission scanning electron microscopy (FESEM) images showed morphological changes in the bacterial surfaces in the presence of C-dots upon laser irradiations, while almost no changes in the bacteria morphology were observed in the presence of C-dots alone. Outer membrane damage was a synergism result of laser irradiation and presence of C-dots.