Rapid Nanofabrication of Nanostructured Interdigitated Electrodes (nIDEs) for Long-Term In Vitro Analysis of Human Induced Pluripotent Stem Cell Differentiated Cardiomyocytes

Abstract

Adverse cardiac events are a major cause of late-stage drug development withdrawals. Improved in vitro systems for predicting cardiotoxicity are of great interest to prevent these events and to reduce the expenses involved in the introduction of cardiac drugs into the marketplace. Interdigitated electrodes (IDEs) affixed with a culture well provide a simple, suitable solution for in vitro analysis of cells because of their high sensitivity, ease of fabrication, and label-free, nondestructive analysis. Culturing human pluripotent stem cell differentiated cardiomyocytes onto these IDEs allows for the use of the IDE–cell combination in predictive toxicity assays. IDEs with smaller interdigitated distances allow for greater sensitivity, but typically require cleanroom fabrication. In this communication, we report the definition of a simple IDE geometry on a printed nanostructured substrate, demonstrate a Cellular Index (CI) increase from 0 to 7.7 for human cardiomyocytes, and a decrease in CI from 2.3 to 1 with increased concentration of the model drug, norepinephrine. The nanostructuring results in an increased sensitivity of our 1 mm pitch IDEs when compared to traditionally fabricated IDEs with a pitch of 10 μm (100 times larger electrode gap). The entire nanostructured IDE (nIDE) is fabricated and assembled in a rapid nanofabrication environment, thus allowing for iterative design changes and robust fabrication of devices.

Optimization of makerspace microfabrication techniques and materials for the realization of planar, 3D printed microelectrode arrays in under four days

“…MEAs along with cells allow for prediction of a drug's behavior prior to clinical trials and evades numerous, expensive late stage drug development failures and market withdrawals. 2,3 MEAs are used to monitor the electrical signals emanating from electrogenic cells or to stimulate these cells electrically. These measurements are made in real-time, allowing researchers to study how a cluster of cells reacts in a small network area in vitro in the vicinity of the microelectrode with great accuracy.…”

Low-Power, Multimodal Laser Micromachining of Materials for Applications in sub-5 µm Shadow Masks and sub-10 µm Interdigitated Electrodes (IDEs) Fabrication

“…The laser micromachined shadow masks were further used to pattern both metal and gelatin/bio-ink as described in Section 4.5. The organic and inorganic layer patterning can be utilized for applications such as accurate cell placement in single cell and culture assays, precision confinement and growth of cellular constructs, tissue engineering, metal micro/nanoelectrodes, definition of organic insulation layers, and other lab-on-a-chip and diagnostic applications [3,23,41,49,51].…”

Simulation and Experiment for Electrode Coverage Evaluation by Electrochemical Impedance Spectroscopy Using Parallel Facing Electrodes

“…evaluate impedance sensors. 4,30,31 The experiment was performed in the range of   0 -30 since  of the undiluted suspension was 30. The latex beads suspension was diluted with 10 mM phosphate buffered saline (Wako 164-18541) so that the electrode coverage  became 0%, 10%, 20% and 30% when all the beads were precipitated on the electrode surface.…”