Morphologically Tunable MnO2 Nanoparticles Fabrication, Modelling and Their Influences on Electrochemical Sensing Performance toward Dopamine

Abstract

Abstract:The morphology or shape of nanomaterials plays an important role in functional applications, especially in the electrochemical sensing performance of nanocomposites modified electrodes. Herein, the morphology-dependent electrochemical sensing properties of MnO 2 -reduced graphene oxide/glass carbon electrode (MnO 2 -RGO/GCE) toward dopamine detection were investigated. Firstly, various morphologies of nanoscale MnO 2 , including MnO 2 nanowires (MnO 2 NWs), MnO 2 nanorods (MnO 2 NRs), and MnO 2 nanotubes (MnO 2 NTs), were synthesized under different hydrothermal conditions. Then the corresponding MnO 2 -RGO/GCEs were fabricated via drop-casting and the subsequent electrochemical reduction method. The oxidation peak currents increase with the electrochemical activity area following the order of MnO 2 NWs-RGO/GCE, MnO 2 NTs-RGO/GCE, and MnO 2 NRs-RGO/GCE. The spatial models for MnO 2 NWs, MnO 2 NTs, and MnO 2 NRs are established and accordingly compared by their specific surface area, explaining well the evident difference in electrochemical responses. Therefore, the MnO 2 NWs-RGO/GCE is selected for dopamine detection due to its better electrochemical sensing performance. The response peak current is found to be linear with dopamine concentration in the range of 8.0 × 10 −8 mol/L-1.0 × 10 −6 mol/L and 1.0 × 10 −6 mol/L-8.0 × 10 −5 mol/L with a lower detection limit of 1 × 10 −9 mol/L (S/N = 3). Finally, MnO 2 NWs-RGO/GCE is successfully used for the determination of dopamine injection samples, with a recovery of 99.6-103%. These findings are of great significance for understanding the relationship between unlimited nanoparticle structure manipulation and performance improvement.

Determination of Uric Acid in Co-Presence of Dopamine and Ascorbic Acid Using Cuprous Oxide Nanoparticle-Functionalized Graphene Decorated Glassy Carbon Electrode

“…The oxidation peak current was proportional to the concentration of UA in the ranges of 2.0 nM−0.6 µM and 0.6 µM−10 µM, respectively, with a low limit of detection (S/N = 3, 1.0 nM) after an accumulation time of 120 s. Cu 2 O-ErGO/GCE was utilized for the rapid detection of UA in human blood serum and urine samples with satisfactory results. when detecting UA with bare electrodes since they have similar oxidation peak potentials [10][11][12]. Nanocomposite-modified electrodes can improve the anti-interference performance and selectivity, which is a common method that is used to solve this problem.…”

“…At present, many chemically modified electrodes have been proposed for the determination of UA [9,[13][14][15][16][17][18][19][20][21][22] although their selectivity is limited, especially due to the coexistence of DA and AA. Hence, developing a modified electrode with high sensitivity and selectivity to meet clinical demands is still challengeable and desirable.Catalysts 2018, 8, x FOR PEER REVIEW 2 of 15 potentials [10][11][12]. Nanocomposite-modified electrodes can improve the anti-interference performance and selectivity, which is a common method that is used to solve this problem.…”

“…Catalysts 2018, 8, x FOR PEER REVIEW 2 of 15 potentials [10][11][12]. Nanocomposite-modified electrodes can improve the anti-interference performance and selectivity, which is a common method that is used to solve this problem.…”

Application of carboxylic acid-functionalized of graphene oxide for electrochemical simultaneous determination of tryptophan and tyrosine in milk

“…Chemical modification of electrodes with suitable materials could solve these problems. Commonly, many nano structure materials such as polymer a nanocomposite [20][21][22][23][24][25], metal nanoparticles [26][27][28], and graphene nanocomposite [15,[29][30][31][32][33][34][35] have been introduced to enhance the electrode performance.…”

“…One of the most common functionalization is utilizing nanoparticles as a promising way to make nanoscale composite electrodes [21,48]. By enhancing properties of these host material, they are applicable in catalysis, opto-electronic materials, surface enhanced Raman Scattering, and biomedical fields [27,31,49,50]. It is worth noting that the modification of GO with carboxyl groups enhances both selectivity and sensitivity for electrochemical determination of Trp and Tyr.…”