Selective Electrochemical Detection Of Dopamine Research Articles

Bismarck brown-assisted hydrothermal synthesis of nitrogen-modified reduced graphene oxide for selective electrochemical detection of dopamine

Metal-free nitrogen-modified reduced graphene oxide (N-rGO) samples were prepared by convenient and cost-effective hydrothermal treatment of graphene oxide using two different concentrations of Bismarck Brown, namely 20 wt.% (rGO_BB20) and 50 wt.% (rGO_BB50). The synthesized N-rGO samples served as an electroactive platform for the highly selective electrochemical detection of dopamine (DA). Structural characterization using XPS demonstrated that Bismarck Brown-assisted hydrothermal treatment of GO leads to incorporation of nitrogen functional groups into the structure of graphene-based material, as evidenced by an increase in the nitrogen content in rGO_BB20 (3.8 at.%) and rGO_BB50 (10.6 at.%). Raman spectroscopy revealed increased FWHM(G) values for both samples, indicating interrupted carbon lattices and higher defective degrees due to nitrogen incorporation. Notably, rGO_BB20 exhibited a higher concentration of quaternary nitrogen species (6.1%), a larger specific surface area (52 m2 g−1), and higher electrical conductivity compared to rGO_BB50. This led to superior electrochemical performance, with rGO_BB20 demonstrating a lower detection limit (45 nM), higher sensitivity (0.61 μA μM−1 cm−2) in a 0–15 μM linear range, and 0.39 μA μM−1 cm−2 sensitivity in a wider 15–476 μM linear detection range compared to rGO_BB50. The proposed sensor displayed exceptional selectivity, reproducibility, repeatability, and stability.

Tailoring cellulose paper via electroless CuSnB deposition for selective electrochemical detection of dopamine.

A novel, biodegradable substrate based, and cost-effective flexible electrochemical sensor was developed for the highly selective and sensitive detection of one of the major neurotransmitters, dopamine, which can be utilised as a disposable electrode for point-of-care diagnostic applications. The active material CuSnB decorated over cellulose paper exhibits good sensitivities of 3.92 μA μM-1 cm-2 with a limit of detection of 0.5 nM. Moreover, the flexible sensor demonstrated superior selectivity towards co-existing metabolites such as ascorbic acid, glucose, and uric acid, in addition to stability at various mechanical deformations.

A simple microfluidic redox cycling-based device for high-sensitive detection of dopamine released from PC12 cells

Here, ITO electrodes modified with Au nanoparticles (AuNPs) were used to fabricate a microfluidic redox cycling-based chip device (AuNPs-MRECD) for highly sensitive and selective electrochemical detection of dopamine (DA). Briefly, ITO electrodes, each with a ∼ 3.2 × 3.2 mm2 working area, were fabricated using photolithography and dry etching processes. Afterward, the electrodes were modified with Au nanoparticles (AuNPs) electrochemically and used in the assembly of AuNPs-MRECD, in which case one AuNPs-ITO was mounted on top of another using a PET film spacer, which also defined the microfluidic channel of the device. According to the results, AuNPs-MRECD exhibited an excellent redox cycling efficiency with an amplification factor (Af) of 4.22 and a collection efficiency (Ce) of 93.7 %. Next, AuNPs-MRECD was tested for sensitive and selective detection of DA; where the device displayed an LOD of 27.9 nM over a linear detection range of 50 to 1000 nM based on reduction current. Finally, the device was successfully applied to the detection of DA released from PC12 cells, suggesting that the device is a promising tool for evaluating dopaminergic cells and the effects of dopaminergic drugs.

Highly Sensitive and Selective Electrochemical Detection of Dopamine and Uric Acid Using Sea Urchin-like Tungsten Oxide Nanostructure Modified SPCE

Highly Sensitive and Selective Electrochemical Detection of Dopamine and Uric Acid Using Sea Urchin-like Tungsten Oxide Nanostructure Modified SPCE

Hexagonal basalt-like ceramics LaxMg1-xTiO3 (x = 0 and 0.5) contrived via deep eutectic solvent for selective electrochemical detection of dopamine

Attributed to the increased interest in search of cost effective alternatives for electrochemical sensing materials, alkali and alkaline-earth metal oxides have seized the attention of material researchers. Herein we report the novel approach of deep eutectic solvent (DES) mediated facile solid state synthesis of pure and lanthanum doped magnesium titanate ceramics at 800 °C. The unique hexagonal basalt-like structure achieved for the La-doped ceramic material showed tremendous electrocatalytic activity towards dopamine biomolecules over a wide linear detection range of 5–50 μM. A remarkable limit of detection, 1.32 μM was attained for La-doped magnesium titanate modified glassy carbon electrode. %RSD value of 2.04 and recovery rate of 97.95 in spiked human serum ensures its promising future as a potential, cost effective and ecofriendly electrode modifier in portable dopamine sensors for point of care human serum analysis.

Lemon juice-assisted synthesis of LaMnO3 perovskite nanoparticles for electrochemical detection of dopamine

Dopamine (DA) is a significant neurotransmitter in the central nervous system that controls many physiological functions. The abnormal or imbalance of DA levels in the human body remarkably affects the physiological functions. Therefore, to detect and monitor DA levels in the human body is necessary to control the body functions. In this context, we have prepared well-defined three-dimensional (3D) polyhedron structured lanthanum manganite nanoparticles (LaMnO3 NPs) by using conventional (Cp) and lemon-juice (Lj) assisted routes and utilized as an electrocatalyst for the sensitive and selective electrochemical detection of DA. The crystalline phase and structure of as-prepared LaMnO3 NPs are confirmed by XRD, XPS and TEM analyses. The Lj-LaMnO3 NPs modified glassy carbon electrode (GCE) shows enhanced electrocatalytic activity towards DA oxidation with lower potential compared to the Cp-LaMnO3 NPs and bare GC electrodes. Moreover, Lj-LaMnO3 NPs/GCE exhibited a wide detection window (1–600 µM), lower detection limit (32 nM), good selectivity and stability. Besides, the modified electrodes are successfully used in the real samples analysis such as urine and saliva samples and the obtained recovery values are good and satisfactory. Hence, the Lj-LaMnO3 NPs/GCE can be used to determine the DA level and offers a best matrix for pharmaceutical applications.

Highly sensitive and selective electrochemical detection of dopamine based on CuCrO2-TiO2 composite decorated screen-printed modified electrode

In the present study, a dopamine (DA) sensor was constructed based on a screen-printed carbon electrode (SPCE) combined with CuCrO2-TiO2 composite. The CuCrO2-TiO2 composite was prepared by a self-combustion glycine nitrate process (GNP) and used to the selective and sensitive detection of DA. The prepared CuCrO2-TiO2 composite-modified SPCE electrode revealed an enhanced sensor response to the detection of DA, showing high peak current with less oxidation potential. The surface area and phase evolution of the CuCrO2-TiO2 composite were determined by the glycine-nitrate (GN) ratios. The structures of the prepared material were verified by scanning electron microscopy, X-ray diffraction, and scanning transmission electron microscopy studies. The active surface area of the composite was identified by BET surface area analysis. These studies confirmed the porous structure of the CuCrO2-TiO2 composite. The electrochemical performance of the SPCE/CuCrO2-TiO2 electrode was studied by cyclic voltammetry, electrochemical impedance spectroscopy, and differential pulse voltammetry methods. The SPCE/CuCrO2-TiO2 (GN = 1.5) electrode presented distinguished electrocatalytic activity for the detection of DA with a long linear response range (1–230 µM), low detection limit (0.14 µM), and high sensitivity (16.82 µA µM−1 cm−2). The modified sensor also showed outstanding repeatability, storage stability, reproducibility, and along with acceptable practicality.

A flexible carbon nanotube-modified poly(styrene-butadiene)-based dopamine sensor

In this work, a multi-walled carbon nanotube-modified flexible poly(styrene-butadiene) fiber membrane material was prepared for the sensitive and selective electrochemical detection of dopamine (DA) in human serum and DA injection. The flexible fiber membrane prepared by electrospinning technology is expected to realize its application in wearable devices. The obtained conductive film-based electrochemical sensor can effectively minimize interference caused by ascorbic acid and uric acid. Under the optimized experimental conditions of differential pulse voltammetry, DA gives a linear response in the range of 1–650 μM (R2 = 0.996). The detection limit of DA (signal-to noise ratio = 3) was determined to be 0.062 μM.

Highly sensitive and selective detection of dopamine using overoxidized polypyrrole/sodium dodecyl sulfate-modified carbon nanotube electrodes

Dopamine (DA), an organic chemical neurotransmitter in the human brain, plays important roles in neuronal reward, motor control, and decision making. Thus, accurate quantification of DA concentration is essential for the investigation of various dopaminergic neural circuits and diagnosis of neurological diseases. Herein, we report an overoxidized polypyrrole/sodium dodecyl sulfate (SDS)-modified multi-walled carbon nanotube (OPPy/SDS-CNT) electrode which allows detection of DA with high resolution and selectivity. By using SDS as a dopant and sodium hydroxide (NaOH) as an oxidizing agent, highly sensitive detection of DA down to 5nM with a detection limit of 136pM is achieved. Moreover, due to the strong electrostatic interaction between the negatively-charged electrode and the positively-charged DA molecules, selective electrochemical detection of DA is successfully demonstrated in the presence of ascorbic acid (AA) and glucose (Glc). Lastly, by demonstrating in vitro detection of DA secreted from dopaminergic cells (PC12 cells) and examining biocompatibility of the electrode, we show the potential of our OPPy/SDS-CNT electrode as a promising candidate for a functional neural interface for in vitro and in vivo monitoring of DA concentrations.

Schiff-base reaction induced selective sensing of trace dopamine based on a Pt41Rh59 alloy/ZIF-90 nanocomposite

Zeolitic imidazole frameworks (ZIFs) are a new class of functional porous materials with attractive characters, such as gas storage, selective separation, catalysis, and drug delivery. We report herein using nanoscale ZIF-90 crystals with free aldehyde group of imidazole-2-carboxaldehyde (ICA) ligand for the selective electrochemical detection of dopamine. The averaged adsorption enthalpy ΔH (i.e., isosteric heat) of ZIF-90 to dopamine is estimated as 72 kJ mol−1 according to grand canonical Monte Carlo (GCMC) simulation. With further modification of a Pt41Rh59 alloy nanocatalyst, the electrochemical sensing performances towards dopamine are improved. The synergetic effect generated by a Pt41Rh59/ZIF-90 nanocomposite endows it a low detection limit of 1 nM and good specificity. The different anti-interference mechanisms to coexisting redox active species and amino analogues are also included in this work. The strategy demonstrated here may be extended to tune metal nodes as well as ligands of ZIFs crystals and further regulating their functionalities for different target molecules identification.

The selective electrochemical detection of dopamine in the presence of ascorbic acid and uric acid using electro-polymerised-β-cyclodextrin incorporated f-MWCNTs/polyaniline modified glassy carbon electrode

The present work describes a differential pulse voltammetric determination of dopamine (DA) using a glassy carbon electrode (GCE) modified with poly-beta-cyclodextrin incorporated with oxidised (OH) multi-walled carbon nanotubes (poly-β-CD(f-MWCNTs) and anion-doped polyaniline (PANI) composite. The poly-β-CD(f-MWCNTs)/PANI composite modified electrode was prepared by electropolymerisation of β-CD(f-MWCNTs) on anion-doped polyaniline by scanning repetitively in the phosphate buffer solution (pH 7) from −2.0 to 2.5 V. The as-prepared poly-β-CD(f-MWCNTs)/PANI composite was characterized by scanning electron microscopy, transmission electron microscopy, electrochemical impedance spectroscopy and Fourier transform infrared spectroscopy. The composite presented excellent synergistic effect and shows an enhanced catalytic activity than electrodes modified with poly-β-CD and PANI. In comparison to the CV results of bare GC and modified GCE, the large electrochemical potential difference has achieved via the used of the poly-β-CD(f-MWCNTs)/PANI composite to distinguish the DA from AA and UA with peak-to-peak separations recorded at 244 mV (AA-DA) and 135 mV (DA-UA). Under optimum conditions, differential pulse voltammetric was used to determine the DA, and the voltammetric response of DA was linear over the concentration ranging from 2 μmol L−1 to 24 μmol L−1 with low detection limit (LOD) of 0.0164 μmol L−1 (S/N = 3) and high sensitivity of 26.79 μA μM−1 cm−2. The poly-β-CD(f-MWCNTs)/PANI composite modified electrode exhibits high selectivity in the presence range of potentially interfering uric acid and ascorbic acid even in high concentration. As a proof of concept, the practicality of the sensors was examined in human urine samples, and shows acceptable practicality for the determination of DA.

Au nanoparticles attached Ag@C core-shell nanocomposites for highly selective electrochemical detection of dopamine

Herein, a simple electrochemical sensor for dopamine (DA) detection was developed based on Ag@C core-shell structure and Au nanocomposites (Ag@C/Au). The Ag@C core-shell nanoparticles were synthesized by one-pot hydrothermal method, which were supported on Au nanoparticles in situ reduction process. The as-prepared nanocomposites were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and UV–vis absorption spectra. The electrochemical investigations indicated that Ag@C/Au nanocomposites possessed intriguing properties towards DA. These results could be attributed to the synergistic effect of Ag@C with enhanced substrate accessibility and conductivity, Au nanoparticles with surface of negative charges. Under the optimum experimental conditions, the liner range was 0.5 μM to 27.5 μM, 27.5 μM to 0.2775 mM and 0.2775 mM to 4.278 mM. The detection limit was 0.21 μM (S/N = 3). Furthermore, the electrochemical sensor showed favorable selectivity in the presence of interferents such as ascorbic acid (AA) and uric acid (UA). In general, the work could provide a promising possibility to develop excellent electrochemical sensors for DA detection.

Highly Sensitive and Selective Electrochemical Detection of Dopamine using Hybrid Bilayer Membranes

AbstractThe rapid and precise measurement of dopamine (DA) levels is of great benefit to unveil physiological and pathological processes. The electrochemical detection approaches feature fast DA response, but remain challenging at the moment to realize ultra‐high sensitivity and selectivity to the trace amount of DA, especially in the presence of highly concentrated ascorbic acid (AA, the most common interferent in the human body). To address this issue, a negatively charged hybrid bilayer membrane (HBM) modified gold electrode was designed, which was only attractive to the positive DA but not the negative AA. As a result, this work managed to achieve an ultra‐low detection limit of 0.41 pM DA under the interference of AA of 109 times higher concentration. Such an excellent performance is over three orders of magnitude better than previously reported electrochemical sensing methods, suggesting the promise of applying HBM functionalization in electrochemical and bio‐sensing applications.

Selective electrochemical detection of dopamine based on molecularly imprinted poly(5-amino 8-hydroxy quinoline) immobilized reduced graphene oxide

The dopamine-imprinted conducting polymer film of 5-amino 8-hydroxy quinoline (AHQ) was electrodeposited on reduced graphene oxide (rGO)-modified glassy carbon (GC) electrode and was applied as a molecular recognition element for the selective determination of dopamine. The molecularly imprinted polymer (MIP)-modified electrode showed an excellent affinity towards dopamine due to the presence of imprinted site through hydrogen bonding interaction between dopamine and poly (AHQ) membrane. The molecular recognition ability of MIP-modified electrode was analyzed by cyclic voltammetric and differential pulse voltammetric techniques. The most stable geometry of the template–monomer complex in the pre-polymerization mixture was calculated by computational approaches. The rGO modification augmented both surface area and electron transfer kinetics of the bare electrode. The GC/rGO/MIP electrode possessed 2.83 fold current enhancements when compared to GC/MIP electrode, indicating the improvement in sensitivity due to rGO modification. The limit of detection and sensitivity of GC/rGO/MIP electrode was observed to be 32.7 nM and 13.3 AM−1 cm−2, respectively. The imprinting methodology provided an exceptional selectivity towards the detection of dopamine even in the presence of high concentration of possible physiological interferents. Moreover, the fabricated electrode was successfully employed for the detection of dopamine in human blood plasma samples proving the effectiveness of the sensor for the sensitive detection of dopamine from real samples.

Facile fabrication of a 3,4,9,10-perylene tetracarboxylic acid functionalized graphene-multiwalled carbon nanotube-gold nanoparticle nanocomposite for highly sensitive and selective electrochemical detection of dopamine.

A novel non-enzymatic electrochemical sensor for highly sensitive and selective detection of dopamine was developed based on a 3,4,9,10-perylene tetracarboxylic acid functionalized graphene-multiwalled carbon nanotube-gold nanoparticle nanocomposite modified glassy carbon electrode (PTCA-RGO-MWCNTs-Au NPs/GCE). The nanocomposite film was prepared by a facile, eco-friendly and controllable route and its morphology was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopic (EDX) analysis, and X-ray diffraction (XRD) spectroscopy, respectively. Cyclic voltammetry and chronoamperometry were used for evaluating the electrochemical behaviors of the prepared sensor. The DA sensor exhibited excellent electrochemical performance toward DA with a sensitivity as high as 0.124 μA mM-1, a wide linear range of 1-100 μM and a low detection limit of 0.07 μM (S/N = 3). Moreover, it showed good selectivity toward DA without any obvious interference by AA and UA. Furthermore, the prepared DA sensor was applied to detect DA in real samples with satisfactory results.

Selective electrochemical detection of dopamine in presence of ascorbic acid and uric acid using NiFe2O4-activated carbon nanocomposite modified glassy carbon electrode

Nickel ferrite-Activated carbon nanocomposite was proposed for selective electrochemical detection of dopamine. The nanocomposite was prepared by a simple hydrothermal method and the morphology as well as the crystal pattern was analyzed using transmission electron microscope (TEM) and X-ray diffraction (XRD) respectively. The electrochemical response for dopamine was studied using cyclic voltammetry (CV). The NiFe2O4-AC/GCE showed good catalytic activity towards dopamine and a detection limit of 1 µM and linear range from 100 µM – 700 µM was deduced using differential pulse voltammetry (DPV). The selective detection of dopamine in presence of ascorbic acid (AA) and uric acid (UA) was accomplished. The reproducibility and stability of the modified electrode towards dopamine detection was demonstrated.

A facile one-pot green synthesis of gold nanoparticle-graphene-PEDOT:PSS nanocomposite for selective electrochemical detection of dopamine

A facile one-pot and green method was developed to prepare a nanocomposite of gold nanoparticle (AuNP), graphene (GP) and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS). Graphene was first electro-exfoliated in a polystyrene sulfonate solution, followed by a one-step simultaneous in situ formation of gold nanoparticle and PEDOT. The as-synthesized aqueous dispersion of AuNP-GP-PEDOT:PSS was thereafter used to modify the glassy carbon electrode (GCE). For the first time, the quaternary composite between AuNP, GP, PEDOT and PSS was used for selective determination of dopamine (DA) and uric acid (UA) in the presence of ascorbic acid (AA). In comparison to a bare GCE, the nanocomposite electrode shows considerably higher electrocatalytic activities toward the oxidation of DA and UA due to a synergistic effect between AuNP, GP, PEDOT and PSS. Using differential pulse voltammetry (DPV), selective determination of DA and UA in the presence of AA could be achieved with a peak potential separation of 110 mV between DA and UA. The sensor exhibits wide linear responses for DA and UA in the ranges of 1 nM to 300 μM and 10 μM to 1 mM with detection limits (S/N = 3) of 100 pM and 10 μM, respectively. Furthermore, the proposed sensor was also successfully used to determine DA in a real pharmaceutical injection sample as well as DA and UA in human serum with satisfactory recovery results.

Selective Electrochemical Detection of Dopamine Using Reduced Graphene Oxide Sheets-Gold Nanoparticles Modified Electrode

Selective Electrochemical Detection of Dopamine Using Reduced Graphene Oxide Sheets-Gold Nanoparticles Modified Electrode

Introducing Schottky barrier into electrochemical response: A novel adjusting strategy for designing electrochemical sensors

A novel strategy of using Schottky barrier as a controllable tuning factor for electrochemical detection was proposed. Our results showed that the Schottky barrier height could be tuned purposely by the charged characteristics of adsorbed molecules so that the electrochemical response could be controllably enhanced or weakened. The fabricated 3D Ni/ZnO/CQDs (carbon quantum dots) foam with Schottky interfaces was successfully employed for selective electrochemical detection of dopamine. It is an effective approach to overcome the limit of selective detection of targets with similar redox properties by using electrochemical method. Rational design of Schottky barrier is promising to develop new-type and more effective electrochemical sensors.

Selective Electrochemical Detection of Dopamine on Polyoxometalate‐Based Metal–Organic Framework and Its Composite with Reduced Graphene Oxide

The interfacing of polyoxometalates and reduced graphene oxide (rGO) can be considered to be an effective way to generate hybrid structures which colligates the advantages of both components. Here, a hybrid material (polyoxometalate‐based metal–organic framework (POMOF)/rGO) integrating POMOF and rGO is obtained via a simple one‐pot approach. The as‐prepared materials are used as electrochemical active materials to detect dopamine for the first time. It is shown that the hybridization results in a superior catalytic activity for oxidation of dopamine owing to the synergistic effect between POMOF and rGO, as well as favorable interaction of DA with CC network of the composite. The promoted electron transfer, as well as abundant active sites, open channels, and aromatic planes in the hybrid material produce a wider linear detection range of 1 × 10−6 to 2 × 10−4 m with the lower detection limit of 80.4 × 10−9 m (S/N = 3). Moreover, the developed biosensor also exhibits favorable selectivity, reproducibility, and stability. As a non‐noble metal catalyst constructing from function and structure‐matched building blocks, the prepared POMOF/rGO hybrid material demonstrates its highly promising properties for dopamine detection and the result should promote the further development of POMOF‐based sensors.