Unknown

Dataset Information

0

High temporal resolution measurements of dopamine with carbon nanotube yarn microelectrodes.


ABSTRACT: Fast-scan cyclic voltammetry (FSCV) can detect small changes in dopamine concentration; however, measurements are typically limited to scan repetition frequencies of 10 Hz. Dopamine oxidation at carbon-fiber microelectrodes (CFMEs) is dependent on dopamine adsorption, and increasing the frequency of FSCV scan repetitions decreases the oxidation current, because the time for adsorption is decreased. Using a commercially available carbon nanotube yarn, we characterized carbon nanotube yarn microelectrodes (CNTYMEs) for high-speed measurements with FSCV. For dopamine, CNTYMEs have a significantly lower ?Ep than CFMEs, a limit of detection of 10 ± 0.8 nM, and a linear response to 25 ?M. Unlike CFMEs, the oxidation current of dopamine at CNTYMEs is independent of scan repetition frequency. At a scan rate of 2000 V/s, dopamine can be detected, without any loss in sensitivity, with scan frequencies up to 500 Hz, resulting in a temporal response that is four times faster than CFMEs. While the oxidation current is adsorption-controlled at both CFMEs and CNTYMEs, the adsorption and desorption kinetics differ. The desorption coefficient of dopamine-o-quinone (DOQ), the oxidation product of dopamine, is an order of magnitude larger than that of dopamine at CFMEs; thus, DOQ desorbs from the electrode and can diffuse away. At CNTYMEs, the rates of desorption for dopamine and dopamine-o-quinone are about equal, resulting in current that is independent of scan repetition frequency. Thus, there is no compromise with CNTYMEs: high sensitivity, high sampling frequency, and high temporal resolution can be achieved simultaneously. Therefore, CNTYMEs are attractive for high-speed applications.

SUBMITTER: Jacobs CB 

PROVIDER: S-EPMC4063327 | biostudies-literature | 2014 Jun

REPOSITORIES: biostudies-literature

altmetric image

Publications

High temporal resolution measurements of dopamine with carbon nanotube yarn microelectrodes.

Jacobs Christopher B CB   Ivanov Ilia N IN   Nguyen Michael D MD   Zestos Alexander G AG   Venton B Jill BJ  

Analytical chemistry 20140528 12


Fast-scan cyclic voltammetry (FSCV) can detect small changes in dopamine concentration; however, measurements are typically limited to scan repetition frequencies of 10 Hz. Dopamine oxidation at carbon-fiber microelectrodes (CFMEs) is dependent on dopamine adsorption, and increasing the frequency of FSCV scan repetitions decreases the oxidation current, because the time for adsorption is decreased. Using a commercially available carbon nanotube yarn, we characterized carbon nanotube yarn microel  ...[more]

Similar Datasets

| S-EPMC4944855 | biostudies-literature
| S-EPMC4276597 | biostudies-literature
| S-EPMC6057988 | biostudies-literature
| S-EPMC7175412 | biostudies-literature
| S-EPMC4789747 | biostudies-literature
| S-EPMC9079689 | biostudies-literature
| S-EPMC9080399 | biostudies-literature
| S-EPMC6317378 | biostudies-literature
| S-EPMC6223678 | biostudies-literature
| S-EPMC5837047 | biostudies-literature