RESUMEN
OBJECTIVE: To evaluate the potential of photodynamic therapy (PDT) with blue light-emitting diode (LED) 460 nm at 25, 50 and 100 J/cm2 using three concentrations of acai extracts (100, 40, and 10 mg/ml), in the proliferation and viability of head and neck tumor lines (SCC9). METHODS: Three groups of cells were analyzed for 3 days in an in vitro assay with MTT (3- (4,5-dimethylthiazol-2-yl) -2,5, -diphenyltetrazolium bromide) and crystal violet: cells in the absence of acai extract and PDT (control group); cells in the presence of acai extract and no light; and cells in the presence of acai extract and LED blue light (PDT groups). RESULTS: When using acai as a PS combined with blue LED (460 nm, 0.7466 cm2 , 1000 mW/cm2 ) and irradiation at 25, 50, and 100 J/cm2 , after 72 h, cell viability (p < 0.0001 vs. control, p = 0.0027 vs. 100 mg/ml açai group, p = 0.0039 vs. 40 mg/ml açai group, p = 0.0135 vs. 10 mg/ml açai group; One-Way ANOVA/Tukey) and proliferation (p < 0.05, One-Way ANOVA/Tukey) decreased. CONCLUSION: The acai in question is a potential photosensitizer (PS), with blue light absorbance and efficacy against head and neck tumor lines (SCC9).