Scalable Nanostructured Carbon Electrode Arrays for Enhanced Dopamine Detection

Abstract

Dopamine is a neurotransmitter that modulates arousal and motivation in humans and animals. It plays a central role in the brain "reward" system. Its dysregulation is involved in several debilitating disorders such as addiction, depression, Parkinson's disease, and schizophrenia. Dopamine neurotransmission and its reuptake in extracellular space takes place with millisecond temporal and nanometer spatial resolution. Novel nanoscale electrodes are needed with superior sensitivity and improved spatial resolution to gain an improved understanding of dopamine dysregulation. We report on a scalable fabrication of dopamine neurochemical probes of a nanostructured glassy carbon that is smaller than any existing dopamine sensor and arrays of more than 6000 nanorod probes. We also report on the electrochemical dopamine sensing of the glassy carbon nanorod electrode. Compared with a carbon fiber, the nanostructured glassy carbon nanorods provide about 2× higher sensitivity per unit area for dopamine sensing and more than 5× higher signal per unit area at low concentration of dopamine, with comparable LOD and time response. These glassy carbon nanorods were fabricated by pyrolysis of a lithographically defined polymeric nanostructure with an industry standard semiconductor fabrication infrastructure. The scalable fabrication strategy offers the potential to integrate these nanoscale carbon rods with an integrated circuit control system and with other complementary metal oxide semiconductor (CMOS) compatible sensors.

3D‐Printed Carbon Electrodes for Neurotransmitter Detection

“…To carbonize the electrodes, pyrolysis was performed by rapid thermal processing (RTP) (Figure 1e), a glassy-carbon like surface can be obtained by the pyrolysis step. [19] Figure 1f shows a microscope image of the carbonized microelectrodes.…”

Utilizing surface modification in plasma‐enhanced cyclic etching of tantalum nitride to surpass lithographic limits

“…For the OPL carrier wafer the profile of the Ta emission appears closer to the Si carrier, however, in this case it takes longer for the maximum value to be reached (the seventh cycle). The OPL material is known to contain oxygen, which could be released through exposure to the etch process and induce the tapered sidewall (82°) observed by SEM. This also correlates with the Ta 331 nm OES data trend in relation to the SiO x and Si carriers.…”

“…Titanium and tantalum‐based conductive films have been previously evaluated as gate materials for complementary metal‐oxide‐semiconductor (CMOS) devices . More recently, they have been incorporated as top electrodes for novel memory technologies such as magnetoresistive RAM and hard masks for carbon electrodes utilized in biological sensing . As the trend of downscaling device size continues, the ability to pattern these films at tight pitches with minimal redeposition becomes highly important.…”

3D‐Printed Carbon Electrodes for Neurotransmitter Detection

“…Ther esulting structures were developed in SU-8 developer (propylene glycol monomethyl ether acetate) to remove anything not cross-linked, producing free standing sensors ( Figure 1d). [19] Figure 1f shows am icroscope image of the carbonized microelectrodes. [19] Figure 1f shows am icroscope image of the carbonized microelectrodes.…”

“…To carbonize the electrodes,p yrolysis was performed by rapid thermal processing (RTP) (Figure 1e), ag lassy-carbon-like surface can be obtained by the pyrolysis step. [19] Figure 1f shows am icroscope image of the carbonized microelectrodes.…”