The role of pH fronts in electrotherapy and electrochemotherapy

G. MARSHALL; F. MAGLIETTI; P. TURJANSKI; N. OLAIZ; C. SUÁREZ; S. MICHINSKI; F. MOLINA

Bs As

Workshop; Annual International Conference of the IEEE Engineering in Medicine and Biology Society; 2010

Abstract We present experimental measurements and theoretical predictions of ion transport during in vitro gel electrochemotherapy (ECT) for conditions typical to many clinical studies found in the literature revealing the presence of pH fronts emerging from both electrodes.  Since these pH fronts might give rise to tissue necrosis or plasmid damage, an unwanted condition in clinical applications of ECT and electrogenetherapy, it is important to quantify their extent and evolution. Here we use a tracking technique to follow the space-time evolution of these pH fronts that shows that they scale in time as t1/2, characteristic of a predominantly diffusive process. A comparison of the magnitude of pH fronts in ECT to those arising in electrotherapy (another electric treatment applying constant electric fields) whose main goal is tissue necrosis, shows that, for the same Coulomb dosage, anodic acidification is larger in ECT, suggesting that tissue necrosis could be larger too. We conclude, through experiments and theory, that pH fronts in ECT are immediate and substantial, and we suggest ways to diminish its adverse effects.