[2026] High Density Microelectrode Arrays (HD-MEAs) for Neuron Recordings and Stimulation

Background: High-density microelectrode arrays (HD-MEAs) have revolutionized in-vitro electrophysiology by offering unprecedented spatiotemporal resolution, enabling the detection of subcellular features such as axonal action potential propagation and the precise mapping of functional network connectivity that were previously unattainable with standard low-density arrays. However, the inherent opacity of traditional metal-electrode (e.g, Au,Pt) based HD-MEAs restricts simultaneous morphological visualization with advanced optical microscopy techniques, effectively creating a "black box" around the recorded networks. ¹

PEDOT:PSS, an organic mixed ionic/electronic conductor, has shown promise as an electrode material for MEAs by facilitating ionic and electronic conduction, enhancing biological signal transduction. Its low impedance, volumetric capacitance, transparency, and ease of fabrication also enable simultaneous highly sensitive electrical and optical measurements.²

Aim: This project aims to develop fully transparent, high-density MEAs using the organic mixed ionic-electronic conductor PEDOT:PSS. By utilizing high-conductivity formulations and advanced geometric designs, the project will maximize transparency and signal sensitivity while maintaining compatibility with advanced microscopy.

Assignments:

1. Design & Simulation: Optimize electrode geometry and layout to minimize crosstalk and impedance using Finite Element Analysis (FEA).

2. Fabrication: Develop a scalable photolithographic workflow for high-conductivity PEDOT:PSS on flexible substrates.

3. Characterization: Optical characterization with optical transmittance measurements, electrochemical characterization with techniques like CV and EIS and material characterization with Raman Spectroscopy, SEM and AFM.

4. Biological Validation: Establish an iPSC derived neuronal culture on top of the HD-MEA with neuronal recordings. 

References

1.                Müller J, Ballini M, Livi P, et al. High-resolution CMOS MEA platform to study neurons at subcellular, cellular, and network levels. Lab Chip. 2015;15(13):2767-2780.

2.                Kim HW, Kim J, Kim JY, et al. Transparent, metal-free PEDOT:PSS neural interfaces for simultaneous recording of low-noise electrophysiology and artifact-free two-photon imaging. Nat Commun. 2025;16(1):4032.

Requirements

Requirements:

MSc students from Microelectronics are welcomed to apply. Interested students should contact Professor Achilleas Savva (a.savva@tudelft.nl), by including their CV, the list of courses attended, and a motivation letter. The student will work closely with Ir. Mustafeez Sha, a PhD candidate expert on microfabrication of PEDOT:PSS electrodes.

Contact

Last modified: 2026-02-09