Selective Determination of Dopamine on a Boron‐Doped Diamond Electrode Modified with Gold Nanoparticle/Polyelectrolyte‐coated Polystyrene Colloids

Abstract

Negatively charged gold nanoparticles (AuNPs) and a polyelectrolyte (PE) have been assembled alternately on a polystyrene (PS) colloid by a layer‐by‐layer (LBL) self‐assembly technique to form three‐dimensional (Au/PAH)4/(PSS/PAH)4 multilayer‐coated PS spheres (Au/PE/PS multilayer spheres). The Au/PE/PS multilayer spheres have been used to modify a boron‐doped diamond (BDD) electrode. Cyclic voltammetry is utilized to investigate the properties of the modified electrode in a 1.0 M KCl solution that contains 5.0 × 10−3 M K3Fe(CN)6, and the result shows a dramatically decreased redox activity compared with the bare BDD electrode. The electrochemical behaviors of dopamine (DA) and ascorbic acid (AA) on the bare and modified BDD electrode are studied. The cyclic voltammetric studies indicate that the negatively charged, three‐dimensional Au/PE/PS multilayer sphere‐modified electrodes show high electrocatalytic activity and promote the oxidation of DA, whereas they inhibit the electrochemical reaction of AA, and can effectively be used to determine DA in the presence of AA with good selectivity. The detection limit of DA is 0.8 × 10−6 M in a linear range from 5 × 10−6 to 100 × 10−6 M in the presence of 1 × 10−3 MAA.

Electrochemical Determination of Dopamine Based on Carbon Nanotube-Sol-Gel Titania-Nafion Composite Film Modified Electrode

“…The high sensitivity of the present DA sensor based on the CNT-titaniaNafion/GC electrode can be attributed to the porous nature of sol-gel titania-Nafion composite film as well as the electrocatalytic effect of CNT. As summarized in Table 1, the present DA sensor based on the CNT-titania-Nafion/GC electrode displayed a relatively low detection limit even without the additional loading of noble metal NPs such as Pt, Au and Pd [11][12][13][14] or a complicated CNT modification step. [18][19][20] However, the present sensor showed a relatively wide linear dynamic range from 0.5 μM to 500 μM.…”

“…[2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21] These include pretreatment and modification of electrode surface with various materials such as self-assembled monolayers, 4,5 permselective film coatings such as Nafion 6 and electropolymerized polymer, 7 zeolite, 2 cyclodextrins, 8 and DNA. 9 Because of the excellent electrocatalytic activity of noble metal nanoparticles (NPs), [11][12][13][14] carbon based nano-materials such as nanofiber, 15 graphene, 17 and nanotube, 10,[18][19][20] the DA sensors based on these nano-materials exhibited good sensitivity and stability. Despite of these great advantages of those carbonbased nano-materials, the insolubility of them, especially carbon nanotube (CNT), in most solvents is one of the most difficult obstacles for their wide application in electrochemical sensors.…”

Selective detection of dopamine using a combined permselective film of electropolymerized (poly-tyramine and poly-pyrrole-1-propionic acid) on a boron-doped diamondelectrode

“…[19][20][21] Modified BDD electrodes for the selective determination of DA have been reported. 1,19,22,23 Of particular interest is the selectivity towards DA by anodical treatment, 23 and the electrodeposition of a poly(N,N-dimethylaniline) film. 1 surface to form a thin 'layer-by-layer' film with synergistic permselectivity against ascorbic and uric acids.…”

Electrochemical Detection of Catechol on Boron‐doped Diamond Electrode Modified with Au/TiO2 Nanorod Composite

“…The prepared materials were characterized by TEM and scanning electron microscopy (SEM, LE01530VP, Zeiss, Germany). Preparation of the BDD electrode 15 BDD electrodes were prepared by a microwave-assisted plasma chemical vapor deposition (CVD) technique on silicon (100) wafers, using a commercial microwave plasma reactor (ASTeX Corp., Woburn, MA) at 5 kW with high purity hydrogen as the carrier gas. First, the silicon substrates were hand-polished with diamond powder (0.5 mm) for nucleation, they were then rinsed with 2-propanol.…”

“…[7][8][9][10][11] On the other hand, nanomaterial-modified electrodes have been increasingly attended aiming to attain better performance by enhancing the electrode conductivity, facilitating the electron transfer and improving the sensitivity and selectivity. [12][13][14][15][16] Moreover, due to their structure-, sizedependent properties, the materials with various shapes have distinct effects on electrode modification. [17][18][19] The metal/TiO 2 composites with different nano-structure have been reported to construct electrochemical sensors due to their superior properties such as high active electrode surface area, good biocompatibility, high electrocatalytic activity, long-term chemical stability and interface-dominated properties.…”