TY - GEN
T1 - Development of pulsed blue light technologies for bacterial biofilm disruption
AU - Bumah, Violet V.
AU - Masson-Meyers, Daniela
AU - Castel, Dawn
AU - Castel, Chris
AU - Enwemeka, Chukuka S.
N1 - Publisher Copyright:
© 2019 SPIE.
PY - 2019
Y1 - 2019
N2 - In recent studies, we showed that pulsed blue light is more potent in suppressing bacterial growth than continuous wave blue light. The potency of pulsed blue light makes it a viable antimicrobial for suppressing bacteria growth in biofilms, where the protective cover of the biofilm makes it is tougher to suppress bacteria. Consequently, we studied the efficacy of pulsed 450 nm light in suppressing the growth of MRSA and P. acnes biofilms. The results showed 100% bacterial suppression in planktonic cultures of MRSA irradiated with 7.6 J/cm2 three times a day, using 3 mW/cm2 irradiance, and in P. acnes planktonic cultures irradiated with 5 J/cm2 thrice daily for 3 days, using 2 mW/cm2 irradiance. However, a similar 100% suppression was not attained in MRSA or P. acnes biofilms irradiated thrice daily for 3 days at various fluences; but LIVE/DEAD assay showed a degree of bacterial suppression, with more live cells in controls than irradiated biofilms, and more dead cells in irradiated than control biofilms. In addition, while control biofilms had intact biofilm networks, irradiated biofilms had disrupted biofilm. The higher the dose, the more bacterial suppression and biofilm disruption. These findings confirm our previous reports that 100% bacterial suppression is attainable with pulsed blue light, and suggests further modification of the treatment protocol in order to achieve 100% bacterial suppression in biofilms.
AB - In recent studies, we showed that pulsed blue light is more potent in suppressing bacterial growth than continuous wave blue light. The potency of pulsed blue light makes it a viable antimicrobial for suppressing bacteria growth in biofilms, where the protective cover of the biofilm makes it is tougher to suppress bacteria. Consequently, we studied the efficacy of pulsed 450 nm light in suppressing the growth of MRSA and P. acnes biofilms. The results showed 100% bacterial suppression in planktonic cultures of MRSA irradiated with 7.6 J/cm2 three times a day, using 3 mW/cm2 irradiance, and in P. acnes planktonic cultures irradiated with 5 J/cm2 thrice daily for 3 days, using 2 mW/cm2 irradiance. However, a similar 100% suppression was not attained in MRSA or P. acnes biofilms irradiated thrice daily for 3 days at various fluences; but LIVE/DEAD assay showed a degree of bacterial suppression, with more live cells in controls than irradiated biofilms, and more dead cells in irradiated than control biofilms. In addition, while control biofilms had intact biofilm networks, irradiated biofilms had disrupted biofilm. The higher the dose, the more bacterial suppression and biofilm disruption. These findings confirm our previous reports that 100% bacterial suppression is attainable with pulsed blue light, and suggests further modification of the treatment protocol in order to achieve 100% bacterial suppression in biofilms.
KW - Antimicrobial therapy
KW - Biofilm formation
KW - Methicillin-resistant Staphylococcus aureus
KW - Printed LEDs
KW - Propionibacterium acnes
KW - Pulsed blue light
UR - http://www.scopus.com/inward/record.url?scp=85072197268&partnerID=8YFLogxK
U2 - 10.1117/12.2510699
DO - 10.1117/12.2510699
M3 - Conference contribution
AN - SCOPUS:85072197268
T3 - Proceedings of SPIE - The International Society for Optical Engineering
BT - Photonic Diagnosis and Treatment of Infections and Inflammatory Diseases II
A2 - Dai, Tianhong
A2 - Popp, Jurgen
A2 - Wu, Mei X.
PB - SPIE
T2 - Photonic Diagnosis and Treatment of Infections and Inflammatory Diseases II 2019
Y2 - 4 February 2019 through 5 February 2019
ER -
