Delaying the Onset of Resistance Formation: Effect of Manipulating Dose, Wavelength, and Rate of Energy Delivery of 405-, 464-, and 850-Nanometer Light for Staphylococcus aureus.

Objective: To determine whether manipulation of dose, wavelength, and rate of energy delivery could delay the onset of previously demonstrated Staphylococcus aureus resistance to blue light.

Methods: The organism was treated in vitro with 405 nm, 464 nm, and combined 464 nm and with 850 nm light emitted from a supraluminous diode (SLD) array. Doses of 9 J/cm2 and 30 J/cm2 were used.

Inactivation of Candida albicans following exposure to 624-nanometer light from a supraluminous diode array.

Objective: To determine the potential for visible light (405 or 624 nm) to produce an inhibitory effect on Candida albicans. In addition, the study sought to evaluate a series of doses in terms of their respective inhibiting capabilities.

Background Data: The authors have studied the effect of blue light on Staphylococcus aureus and found that a bactericidal outcome can be obtained with low doses of blue light.