A Low-Cost, Scalable, and Configurable Multi-Electrode System for Electrical Bio-Interfacing with In-Vitro Cell Cultures

Abstract

Electrical intervention has been one of the prime approaches in therapeutics in recent times. Research studies have reported several instances of electrical intervention in in vitro, in vivo, ex vivo, and clinical experiments. In vitro research shows a direct relationship between applied modulation and changes in a biological entity and leads to proof of theory. Although the stimulus used in in vitro experiments is current, voltage, or electric field, the ionic current flowing through the biological samples is the key factor in biomodulation. The direction and density of ionic current through the biological sample depend heavily on the experimental setup and electrode configuration. Bio-interfacing electrodes within a biological system have been a matter of concern in in vitro experiments, leading to various expensive and commercially available electrode setups. However, most of the setups are tailored for a specific experiment and cannot be altered as required. This paper demonstrates a multi-electrode system designed for in vitro experiments in standard 24-well culture dishes. The electric field distribution and current density of the setup were analyzed using COMSOL Multiphysics. The system is designed using standard PCB building technology. It can be configured into bipolar or tetrapolar setups. The system was used to measure in vitro bio-impedance in a 24-well culture dish for both bipolar and tetrapolar configurations. Bio-compatibility was observed by keeping the system in contact with human dermal fibroblasts (HDFs) in an in vitro experiment environment. The results indicate no statistical difference in the proliferation of HDFs due to exposure to electrodes. Moreover, no corrosion on the electrodes was observed. In general, the system is a low-cost, easy-to-make alternative to commercially available in vitro electrical bio-interfacing studies.