Study protocol to determine wavelength, fluence, and irradiance activities of Os-4T:
- Lead in compound family (Os-4T) was applied to SK-MEL-28 melanoma cells in well-plates
- Well-by-well illuminations in triplicates with the ML8500 (37 ⁰C, 5% CO2) using 525 nm and 630 nm wavelengths. In the first experiment, irradiance was kept constant at 300 mW/cm2 and fluence was varied between 10-300 J/cm2, while in the second experiment, fluence was constant at 100 J/cm2 and irradiance varied 25-300 mW/cm2.
- Determine cell viability with Resazurin assay and read absorbance at 570 and 600 nm. Resazurin assay principle: The irreversible reaction of the purple resazurin to the pink-colored resorufin is proportional to aerobic respiration, indicating the amount of viable cells.
Illumination parameters significantly affected the phototoxicity of Os-4T. The green light (525 nm) was more effective than the red light (630 nm) at lower fluences, while the maximal potency was achieved at both wavelengths when using fluences higher than 100 J/cm2. Irradiance affected the potency with both the red and the green light that were more effective when lower irradiances were used.
Graphs from the original publication. Open-access content reproduced with permission from the contact author of the publication.
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