title: The enhancement of neural growth by amino-functionalization on carbon nanotubes as a neural electrode.
abstract: This paper reports the success of amino-functionalization on multi-walled carbon nanotubes (MWCNTs) to promote neuronal cells growth on MWCNT electrode for extracellular recording, attributed to the formation of positive charge of NH(2) molecules on their surfaces. Besides, the surface of MWCNT electrode becomes hydrophilic after amino-functionalization (AF-MWCNTs) which can enhance electrical conductivity because of lower MWCNT/electrolyte interfacial impedance and higher interfacial capacitance. Durability tests show that electrical characteristics of the MWCNTs treated by 2 wt% 1,4-diaminobutane solution (2 wt%-AF-MWCNTs) can last for at least six months in air ambient. The neural recording of crayfish shows that 2 wt%-AF-MWCNTs can provide better capability on detecting action potentials of caudal photoreceptor (CPR) interneuron compared to suction glass pipette from the evidence of a higher S/N ratio (126 versus 23). The amino-functionalized MWCNT electrode is feasible for long-term recording application according to the results of biocompatibility tests. As the MWCNTs were directly synthesized on Si-based substrates by catalyst-assisted thermal chemical vapor deposition (CVD) at a low temperature (400 °C), these self-aligned MWCNT electrodes could be friendly implemented in integrated circuits fabrications.
authors.affiliation: Department of Materials Science and Engineering, National Tsing-Hua University (NTHU), Hsinchu 30013, Taiwan.
authors.forename: Shiang-Jie
authors.initials: SJ
authors.lastname: Yen
authors.forename: Wei-Lun
authors.initials: WL
authors.lastname: Hsu
authors.forename: Yung-Chan
authors.initials: YC
authors.lastname: Chen
authors.forename: Huan-Chieh
authors.initials: HC
authors.lastname: Su
authors.forename: Yen-Chung
authors.initials: YC
authors.lastname: Chang
authors.forename: Hsin
authors.initials: H
authors.lastname: Chen
authors.forename: Shih-Rung
authors.initials: SR
authors.lastname: Yeh
authors.forename: Tri-Rung
authors.initials: TR
authors.lastname: Yew
mesh_terms: D000200:Action Potentials; D000818:Animals; D003400:Astacoidea; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods; D002478:Cells, Cultured; D004553:Electric Conductivity; D017097:Electric Impedance; D055664:Electrochemical Techniques; D004566:Electrodes; D006624:Hippocampus / Q000166:cytology; D066298:In Vitro Techniques; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D037742:Nanotubes, Carbon / Q000737:chemistry / Q000648:ultrastructure; D055495:Neurogenesis; D009457:Neuroglia / Q000166:cytology / Q000378:metabolism; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D056951:Photoelectron Spectroscopy; D051381:Rats
chemical_list: D037742:Nanotubes, Carbon