Oxidation of dopamine on multi-walled carbon nanotubes

Abstract

Novel films consisting of multi-walled carbon nanotubes (MWCNTs) were fabricated by means of the chemical vapor deposition technique with decomposition of either acetonitrile (ACN) or benzene (BZ) in the presence of ferrocene (FeCp 2 ) which served as catalyst. The electrochemical response of the two different kinds of MWCNTbased films, further referred to as MWCNT-ACN and MWCNT-BZ, towards the oxidation of dopamine (DA) to dopamine-o-quinone (DAQ) was tested by means of cyclic voltammetry, differential pulse voltammetry, and electrochemical impedance spectroscopy. Both MWCNT-based films exhibit quasi-reversible response towards DA/DAQ with some slight kinetic differences; specifically, the charge-transfer process was found to be faster on MWCNT-ACN (k s 035.3 × 10 −3 cm s −1 ) compared to MWCNT-BZ (k s 06.55×10 −3 cm s −1 ). The detection limit of MWCNT-BZ for DA (0.30 μM) appears to be poorer compared to that of MWCNT-ACN (0.03 μM), but nevertheless, both MWCNT-based films exhibit greater detection ability compared to other electrodes reported in the literature. The sensitivities of MWCNT-ACN and MWCNT-BZ towards DA/DAQ were determined as 0.65 and 0.22 A M −1 cm −2 , respectively. The findings suggest that the fabricated MWCNT-based electrodes can be successfully applied for the detection of molecules with biological interest.

Multi-walled carbon nanotubes doped with boron as an electrode material for electrochemical studies on dopamine, uric acid, and ascorbic acid

“…B-MWCNTs appear to be more sensitive compared to other materials reported in literature and thus it can be considered as promising material for future applications in electrochemical sensing. [31] c Nitrogen-doped MWCNTs [34] d Nitrogen-doped MWCNTs [30] e Pristine MWCNTs [34] f MWCNTs modified with iron(II) thiocyanate complex [35] …”

“…In addition, the limits of detection of pristine MWCNTs, P-MWCNTs, BMWCNTs, and N-MWCNTs towards oxidation of DA and UA are presented graphically in histograms in Fig. S14 (ESM) [30,31,34,35]. Furthermore, a comprehensive comparison of detection limits of B-MWCNTs and other composite films reported in literature towards oxidation of DA, UA, and AA is shown in Table S3 (ESM).…”

Properties and electrochemical characteristics of boron-doped multi-walled carbon nanotubes

“…The growth processing time was kept constant at about 30 min, and consequently a total volume of 5.0 mL of boric acid/ethyl alcohol/ferrocene ternary mixture was sprayed into the furnace for the production of BMWCNTs. The scheme of CVD apparatus and additional experimental details regarding the spray pyrolysis technique were reported previously [11,12].…”

Boron-doped multi-walled carbon nanotubes as sensing material for analysis of dopamine and epinephrine in presence of uric acid

“…In all cases, the pyrolysis experiments were carried out by spraying a volume of about 5 mL of TEB/EtOH/FeCp2 ternary mixture. The scheme of CVD apparatus and experimental details concerning the pyrolysis process were already reported in previous published articles [23,24].…”