Blue Light Photo-Destroys Methicillin Resistant Staphylococcus aureus (MRSA) In-Vitro

Blue 470-nm Light Kills Methicillin-Resistant Staphylococcus aureus (MRSA) in Vitro

“…These strains represent HA-MRSA and CA-MRSA, respectively, and were identified by standard identification procedures, including Gram's staining, hemolytic patterns seen on blood agar, and catalase and coagulase production. As detailed in our previous reports, 19,20 each strain was separately diluted to a cell count of 5 ϫ 10 6 /mL in 0.9% normal saline. Then they were volumetrically streaked onto round 35-mm plates of tryptic soy agar before being irradiated with the light source.…”

“…To ensure even irradiation of each plate, we used 5.0-cm 2 culture plates, which were the same size as the surface area of the applicator, which was clamped at a distance of 1-2 mm perpendicularly above each open plate. As each dose was selected, the treatment time was automatically computed by the Solaris device to ensure that the bacteria were irradiated with 0, 1, 3,5,7,9,11,13,15,17,19,25,30,35,40,45, 50, 55, or 60 J/cm 2 of energy fluence. For example, to attain a fluence of 3 J/cm 2 , the Solaris device calculated that 100 sec of irradiation was needed, and the device automatically shut down after 100 sec had elapsed.…”

“…In our pioneering studies, 19,20 we showed that 405-nm light kills both HA-MRSA and CA-MRSA in vitro. The effect was dose-dependent, with maximum eradication rates of 92-94% of each type of bacteria occurring within 8-10 min of irradiation.…”

The relative antimicrobial effect of blue 405 nm LED and blue 405 nm laser on methicillin-resistant Staphylococcus aureus in vitro

“…Our laboratory and others have shown repeatedly that blue light in the range of 400-470 nm has antimicrobial effects on a diverse group of bacteria including Propionibacterium acnes, Pseudomonas aeruginosa, Porphyromonas gingivalis, Helicobacter pylori, and methicillin-resistant Staphylococcus aureus (MRSA) [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30]. However, most of the studies in this area have been done with blue LEDs or photodynamic therapy involving the use of blue absorbing dyes, not laser diodes.…”

Laser therapy: A review of its mechanism of action and potential medical applications

“…Shimon Rochkind [22][23][24][25] and Juanita Anders [26][27][28] have contributed to neuroscience. Chukuka Enwemeka's group to wound healing [29][30][31]; Leonardo Longo [32][33][34] and Richard Kolt's [35] studies on diabetes; and Boris and Tomislav Ivandic [36] to AgeRelated Macular Degeneration (AMD). Allan Gardiner has recently reported on the ability of low-intensity light with varying frequency to significantly mitigate Complex Regional Pain Syndrome (CRPS) [37]; Roberta Chow [38][39], Jan Bjordal [40][41][42] and Mary Dyson [43][44] present extensive data on other aspects of pain, pain analysis and numerous other light treatments.…”