Plasma activated solution synergistic with exogenous RONS enhances cancer cell apoptosis for improved tumor therapy

The role of reactive oxygen and nitrogen species (RONS) in plasma-activated solution (PAS) for inducing cancer cell apoptosis is well-established, but suboptimal concentrations and rapid degradation often limit their efficacy. This study addresses a significant gap in current research by exploring how the incorporation of exogenous RONS into PAS can enhance apoptosis in cancer cells, potentially overcoming the limitations of traditional PAS treatments. In this study, the effect of treating saline with a plasma jet for different durations was investigated to analyze how its chemical composition triggers apoptosis in cancer cells in vitro. It was observed that longer plasma treatment times resulted in lower cell viability, the reactive species of H₂O₂, NO₂⁻ and ONOO⁻ were found to play a crucial role in inducing apoptosis in cancer cells. Based on these findings, the anticancer efficacy of PAS was further evaluated after the addition of specific exogenous RONS, using measures such as cell viability, intracellular ROS levels, and microscopic imaging. Biological experiments demonstrated that the anticancer efficacy followed the order: addition of RONS to saline before plasma discharge treatment > addition of RONS to saline after plasma discharge treatment > exogenous RONS solution without plasma treatment. This suggests that the external introduction of RONS can modify the chemical composition of PAS to effectively enhance its anticancer properties, with the addition of H₂O₂ before plasma discharge treatment proving to be the most effective strategy. These results provide a novel perspective on harnessing the anticancer potential of PAS and expanding its potential applications in tumor therapy.