TY - JOUR
T1 - 3D-Printed Carbon Nanoneedle Electrodes for Dopamine Detection in Drosophila
AU - Shao, Zijun
AU - Zhao, He
AU - Dunham, Kelly E.
AU - Cao, Qun
AU - Lavrik, Nickolay V.
AU - Venton, B. Jill
N1 - Publisher Copyright:
© 2024 The Author(s). Angewandte Chemie International Edition published by Wiley-VCH GmbH.
PY - 2024/7/22
Y1 - 2024/7/22
N2 - In vivo electrochemistry in small brain regions or synapses requires nanoelectrodes with long straight tips for submicron scale measurements. Nanoelectrodes can be fabricated using a Nanoscribe two-photon printer, but annealed tips curl if they are long and thin. We propose a new pulling-force strategy to fabricate a straight carbon nanoneedle structure. A micron-width bridge is printed between two blocks. The annealed structure shrinks during pyrolysis, and the blocks create a pulling force to form a long, thin, and straight carbon bridge. Parameterization study and COMSOL modeling indicate changes in the block size, bridge size and length affect the pulling force and bridge shrinkage. Electrodes were printed on niobium wires, insulated with aluminum oxide, and the bridge cut with focused ion beam (FIB) to expose the nanoneedle tip. Annealed needle diameters ranged from 400 nm to 5.25 μm and length varied from 50.5 μm to 146 μm. The electrochemical properties are similar to glassy carbon, with good performance for dopamine detection with fast-scan cyclic voltammetry. Nanoelectrodes enable biological applications, such as dopamine detection in a specific Drosophila brain region. Long and thin nanoneedles are generally useful for other applications such as cellular sensing, drug delivery, or gas sensing.
AB - In vivo electrochemistry in small brain regions or synapses requires nanoelectrodes with long straight tips for submicron scale measurements. Nanoelectrodes can be fabricated using a Nanoscribe two-photon printer, but annealed tips curl if they are long and thin. We propose a new pulling-force strategy to fabricate a straight carbon nanoneedle structure. A micron-width bridge is printed between two blocks. The annealed structure shrinks during pyrolysis, and the blocks create a pulling force to form a long, thin, and straight carbon bridge. Parameterization study and COMSOL modeling indicate changes in the block size, bridge size and length affect the pulling force and bridge shrinkage. Electrodes were printed on niobium wires, insulated with aluminum oxide, and the bridge cut with focused ion beam (FIB) to expose the nanoneedle tip. Annealed needle diameters ranged from 400 nm to 5.25 μm and length varied from 50.5 μm to 146 μm. The electrochemical properties are similar to glassy carbon, with good performance for dopamine detection with fast-scan cyclic voltammetry. Nanoelectrodes enable biological applications, such as dopamine detection in a specific Drosophila brain region. Long and thin nanoneedles are generally useful for other applications such as cellular sensing, drug delivery, or gas sensing.
KW - 3d-printed electrodes
KW - carbon nanoneedle
KW - electrochemistry
KW - nanofabrication
KW - photolithography
UR - http://www.scopus.com/inward/record.url?scp=85196507550&partnerID=8YFLogxK
U2 - 10.1002/anie.202405634
DO - 10.1002/anie.202405634
M3 - Article
AN - SCOPUS:85196507550
SN - 1433-7851
VL - 63
JO - Angewandte Chemie - International Edition
JF - Angewandte Chemie - International Edition
IS - 30
M1 - e202405634
ER -