Involvement of hydrogen peroxide in sonodynamical effect with sinoporphyrin sodium in hypoxic situation

Sonodynamic therapy (SDT) represents a noninvasive therapeutic method via the activation of certain chemical sensitizers using low-intensity ultrasound to generate various reactive oxygen species (ROS). In this work, we conducted systematic experiments to evaluate the production of hydrogen peroxide (H2O2) in sinoporphyrin sodium (DVDMS) mediated SDT (DVDMS-SDT). We found that the fluorescence intensities of H2O2-specific probe BES-H2O2 and Amplex Red increased significantly exposure to DVDMS-SDT while decreased with the introduction of catalase (H2O2 scavenger), indicating the production of H2O2. And the fluorescence intensity of H2O2 susceptible probes were positively correlated with DVDMS concentration, ultrasound intensity and irradiation time. Under the same molarity concentration, DVDMS has advantages over proto-porphyrin IX (PpIX) and hemoporrin monomethyl ether (HMME) in H2O2 production, indicating that the yield of H2O2 depends on the properties of sensitizer. More importantly, DVDMS-SDT is involved in the process of H2O2 even in the oxygen-free condition, showing its greater superiority for the treatment of tumor under hypoxia environment.