Electrochemical treatment of tumors: tracking study of electrodenaturation fronts propagating from a one-probe two-electrode device (OPTED)

OLAIZ NAHUEL; MAGLIETTI FELIPE; SUÁREZ CECILIA; MOLINA FERNANDO; MARSHALL GUILLERMO

Niza

Congreso; 61st Annual Meeting of the International Society of Electrochemistry; 2010

International Society of Electrochemistry

We have recently shown, using a collagen macronutrient gel (CMG) model, that in the classical electrochemical treatment (EChT) of tumors (the passage of a direct electric current through two electrodes inserted locally in the tumor tissue),  from an initial uniform condition two electrodenaturation fronts evolve, expanding towards each other, inducing tumor destruction. Here we present results using a CMG model system in conjunction with one-probe two-electrode device (OPTED) containing the cathode and the anode very close to each other (1 mm). Experiments show that upon application of a potential difference to the CMG-OPTED, two half spherical electrodenaturation fronts (one acid and the other alkaline) expand towards the periphery configuring a distorted full sphere. Tracking of the electrodenaturation front reveals a time scaling close to t1/2, signature of a diffusion-controlled process. An analytic model presented allows the estimation of the time needed for total tumor destruction with a minimum compromise of healthy tissue. The sphere maximum diameter is a function of the dose (charge) applied, as well as the availability of water, which can be exhausted thus stopping the production of H+ and OH-. However, comparing with the separated-electrodes approach currently employed, using the OPTED a gain of about 25% is obtained due to water recombination. Besides, water can be injected to improve conditions as it has been reported. Main advantages of the OPTED-EChT are the insertion of one applicator rather than two or more (thus minimizing tissue intrusion, for instance, in the nervous system) and the minimization of electric current circulation through the treated organ. Moreover, in contrast to previous simpler in vitro models, the use of the CMG model represents a better structural and chemical approximation to a real tissue thus providing a better tool for validation of new in silico EChT models aimed at a more accurate prediction of tissue destruction level.