Abstract
Carboxylated single-walled carbon nanotube thin-film (SWCNT-TF) is demonstrated as a pH electrode and a platform for enzymatic potentiometric acetylcholine biosensors. SWCNT is layer-by-layer assembled with a positively charged polyelectrolyte on the metal electrode. The open circuit potential on SWCNT-TF electrode is measured with reference to an Ag/AgCl electrode in various pH buffers. With the aid of acetylcholinesterase (AchE), acetylcholine (Ach) is successfully detected using the SWCNT-TF pH electrode that demonstrates Nernst potential of -43 mV/pH. AchE-modified electrode has a sensing resolution of 10 μM of Ach and sensitivity of 19 mV/decade. The SWCNT-TF pH electrode fabricated by layer-by-layer self-assembly may play an important role in micro/nanoscale electrochemical sensors.
Original language | English (US) |
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Pages (from-to) | 39-42 |
Number of pages | 4 |
Journal | Microelectronic Engineering |
Volume | 93 |
DOIs | |
State | Published - May 2012 |
Bibliographical note
Funding Information:The authors gratefully acknowledge the support of NSF Grant No. CMMI 0735268 . Parts of this work were carried out in the Characterization Facility and the Nanofabrication Center, University of Minnesota, which are partially supported by NSF.
Keywords
- Acetylcholine sensor
- Carbon nanotube
- Electrochemical biosensor
- Thin film
- pH sensor