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Microphysiological systems are three-dimensional (3D) in vitro systems that recapitulate crucial biological aspects of cell heterogeneity and native tissue architecture by mimicking complex structures that are impossible in two-dimensional (2D) cell cultures. Microelectrode arrays (MEAs) are biosensors used to spatially and temporally monitor the activity of microphysiological systems by transducing cellular signals into electronic signals to provide quantitative data on the in vitro system. Conventional MEAs are typically planar in nature, however, 3D MEAs offer several advantages such as better simulation of an in vivo cellular environment and improved signal-to-noise ratio and cell-electrode coupling. MEA fabrication utilizing traditional cleanroom methods is rather extensive, expensive, and specialized, therefore this thesis presents a transition from 2D MEAs fabricated via the cleanroom approach to 3D MEAs fabricated via the makerspace approach utilizing polymers. The first study in the thesis discussed the fabrication and characterization of 2D MEA devices using cleanroom methods and investigated post-processing methods to address limitations that arise for planar devices. The next study introduced the makerspace approach, where benchtop techniques were used to successfully fabricate and characterize a fully functional 3D MEA. A subsequent study investigated another benchtop method to define an electrical insulation using a pour-spin method of polystyrene solution. However, there was a challenge of adhesion of the PS to the substrate, which was improved by both utilizing another type of printer and functionalizing these surfaces with polydopamine. In the final study of the thesis, a benchtop technique called electrospinning was used to define synthetic polymer-based nanofibers atop of the 3D MEAs to simulate extracellular matrices as well as demonstrate their potential as drug delivery systems. This thesis demonstrates the highly versatile nature of makerspace microfabrication utilizing polymers to allow for new processes that offer advanced functionalities when producing microdevices such as 3D MEAs interfacing with microphysiological systems.