Design and fabrication of microelectrodes for electrical impedance tomography of cell spheroids

Three-dimensional (3D) tumour spheroids exhibit great potential as an in vitro for pharmaceutical drug testing. Spheroids represent more physiologically relevant systems compared to 2D cell culture models. In this work, MCF7 spheroids are cultured in Corning® spheroid microplates to investigate cell morphology and proliferation. Platinum microelectrodes designed to enable electrical impedance tomography (EIT) imaging were fabricated on glass substrates. EIT measurements were performed on 250 μm radius circular electrode tips for 0.71 mm MCF7 spheroid at 20 kHz using time difference imaging method. Initial results indicate the capability of EIT to image cell spheroids.