The effect of dual-frequency ultrasound waves on B16F10 melanoma cells: Sonodynamic therapy using nanoliposomes containing methylene blue.

Abstract

We investigated the effect of dual-frequency sonication on the viability of B16F10 melanoma cells in the presence of methylene blue (MB) encapsulated in nanoliposomes. Treatment protocols were studied: sonication groups (40kHz, 1MHz and dual-frequency), the same sonication groups with nanoliposomes containing MB, MB free and nanoliposomes containing MB groups, and so sham and control groups. The nanoliposomes were prepared by the lipid film hydration method. The cell viability of the different treatment groups was evaluated by the MTT assay. The dual-frequency protocols caused higher viability losses compared to the kHz and MHz sonications (P<.05). In presence of the nanoliposomes containing MB, dual frequency led to 6% and 3% viability for 600 and 1200seconds, respectively, while the corresponding values were 10% and 4% for the 40kHz protocols and 22% and 9% for the 1MHz, as compared to the control group (100%). The result of KI dosimetry showed that the cavitation activity of the dual-frequency protocol was about 1.23, as compared to sonication at 40kHz and 1MHz. Enhancement of inertial cavitation induction by dual-frequency sonication may be the primary effective mechanism, which causes increased sonochemical processes and drug release from nanocarriers.