Low cost SU-8 lift-off process to fabricate a gold/glass microelectrodes array for culturing applications.

In this paper, a procedure to release SU-8 layers from glass substrates using typical undesirable effects is described. The proposed process can be used as lift off or stripping. The releasing method consists in taking advantage of the undesired thermal delamination, and the effect of UV overexposure on the delamination temperature, which are considered undesirable effects. This implies the use of SU-8 for both structural and lift off using the same facilities, without any additional photoresist, material, remover or developer. In this way, the fabrication of a glass/gold microelectrodes array (MEA) for cell culture applications is carried out as a proof of concept. The MEA is composed of gold tracks of 1.5 mm width and 8 electrodes with radii between 25 and 500 μ m at its ends. The SU-8 photoresist is also used as an insulation layer releasing the pads and the electrodes. Finally, biological experiments with neuroblastoma cells SK-N-SH cultured on the MEA surface were carried out in order to validate and demonstrate the biocompatibility of both the MEA and the process. The fabrication and biological results were successful, showing a normal cell proliferation over the developed MEA. [ABSTRACT FROM AUTHOR]