Continuous electrochemical H₂O₂ delivery for cancer cell treatment

Hydrogen peroxide (H₂O₂) has emerged as a promising agent in cancer therapy due to its ability to induce oxidative stress selectively in tumor cells, however, its efficacy is severely hampered by H₂O₂ breakdown when administered via standard routes. Our study introduces an innovative electrochemical method for the controlled and continuous delivery of H₂O₂ directly to cancer cells, potentially enhancing the efficacy of cancer treatments. We investigated the performance of gold, titanium, stainless steel, and poly(3,4-ethylenedioxythiophene), PEDOT, electrodes in generating H₂O₂, with PEDOT exhibiting superior consistency and efficiency in cell culture medium. The galvanostatic delivery of H₂O₂ demonstrated a dose-dependent reduction in cell viability for U87 glioblastoma and A375 melanoma cells, confirming the cytotoxic impact of H₂O₂. The addition of catalase restored cell viability, further validating the specificity of H₂O₂-induced cell death. Our results showed that U87 cells exhibited higher resistance to H₂O₂ compared to A375 cells, aligning with known tumor-specific variations in H₂O₂ metabolism. This novel approach of electrochemical H₂O₂ delivery holds significant potential for enhancing targeted cancer therapies, offering a controllable, precise, and efficient method for inducing tumor cell death while minimizing damage to healthy tissues. These results showcase the remarkable ability of PEDOT electrodes as a reliable electrocatalytic source of on-demand H₂O₂ in electrochemically-challenging biological environments.