Sensor For Determination Of Dopamine Research Articles

A simple and accurate ratiometric sensor for determination of dopamine based on dual-emission carbon dots.

Dopamine (DA) is a neuromodulatory molecule that plays critical roles in many biological processes. The dysfunctions of the DA system are closely associated with several nervous system diseases. Therefore, it is urgent to establish a simple and accurate method for DA analysis. In this study, an economic and accurate DA ratiometric sensor was established using dual-emission carbon dots (DE-CDs). DE-CDs were first synthesized by the one-step solvothermal method and two separate fluorescence emission peaks at 340 and 500nm were observed under the excitation of 310nm. In the presence of Hg2+, the fluorescence signal at 340nm was significantly quenched, while the signal at 500nm keeps stable. Upon adding DA, the quenched signal at 340nm was significantly recovered, whereas the signal at 500nm remains stable. Therefore, a novel ratiometric sensor for DA analysis was established. This method shows a good linear range from 500nM to 100μM, and the detection limit was calculated to be 80nM. Moreover, this established method shows excellent specificity and could be applied in real sample analysis, showing great potential for application in clinical research.

Determination of dopamine in blood serum and urine samples by differential pulse voltammetry at an iodine-coated platinum electrode

While platinum electrode shows hyperactivity towards adsorption and surface processes, iodine-coated platinum electrode offers remarkable inertness toward them. Therefore, iodine-coated platinum electrodes lend themselves to probe chemical species in the bulk solution without intervention from adsorption and surface processes. The current work presents utilization of iodine-coated polycrystalline platinum electrode as a voltammetric sensor for determination of dopamine in serum and urine samples. Differential pulse voltammetry (DPV) at iodine coated polycrystalline platinum electrode is the technique of choice whenever higher sensitivity is sought. DPV with a scan rate of 5 mV/s was applied for determination of dopamine in PBS at pH 7. The anodic peak related to dopamine oxidation in the above-mentioned solution was centered at ~0.1V vs. Ag/AgCl quasi reference electrode. The linear range for the developed method was between 1.0 and 100 µM. The anodic peak current showed excellent linearity with dopamine concentration (R2 =0.9977) over the above-mentioned range. The limit of detection (LOD) and limit of quantitation (LOQ) were 0.29 µM and 0.96 µM respectively which attests to the high sensitivity of the developed method. The proposed method was successfully applied to the analysis of dopamine in serum and urine samples. The percent recovery values ranged from 94.4 to 104.5% attesting to the accuracy of the developed method and absence of determinate errors.

A cobalt(ii) coordination polymer with 6-aminonicotinate and 1,2-bis(4-pyridyl)ethane as a new electrochemical sensor for determination of dopamine

Dopamine (DA), a typical and representative catecholamine, is crucial for medical treatment and clinical analysis because it is an essential neurotransmitter.

Synthesis, characterization and sensing application of HNTs@Pd-MoS2 ternary composite

In the current study, halloysite nanotube@palladium-molybdenum disulfide ternary composite (HNTs@Pd-MoS2) was synthesized. The characterization of HNTs@Pd-MoS2 ternary composite were carried out by Scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDX), Transmission electron micrsocopy (TEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) analysis and X-ray photoelectron spectroscopy (XPS). The as-synthesized HNTs@Pd-MoS2 ternary composite was utilized to prepare a sensor for electrochemical determination of dopamine. For this purpose, glassy carbon electrode (GCE) was modified with HNTs@Pd-MoS2 composite (HNTs@Pd-MoS2/GCE), and the modified electrode was utilized for electrochemical determination of dopamine in phosphate buffer solutions. Under optimal conditions, the improved electrosensor demonstrated considerable response toward electrocatalytic oxidation of dopamine with tip a well linearity in the concentration range of 25–1000 μM. The detection limit (LOD) of the recommended electrosensor was forecasted to be 0.15 μM. The effectiveness of the proposed electrosensor was tested against some interferant substances such as uric acid, glucose, ascorbic acid and acetaminophen. The results showed that the proposed electrosensor does not have a significant current response to such interference materials. Furthermore, HNTs@Pd-MoS2/GCE demonstrated a considerable reproducibility and fast-response time. As a result, it can be proffered that the modified GCE can be evaluated as an electrochemical sensor for determination of dopamine.

Electrochemical Construction of a Polymer-Metal Complex Surface Network for Selective Determination of Dopamine in Blood Serum

A surface base polymeric film was fabricated onto a glassy carbon electrode (GCE) via reversible voltammetric scanning in acidic electrolyte containing a (2,4,6-triaminopyrmidine) monomer (TP). The assembled poly(2,4,6-triaminopyrmidine) (PTP) surface material was further modified by electrochemical attachment of tris(2,2'-bipyridine) ruthenium(II) described as Ru(II)-complex. The structure and electrochemical properties of the resulting (Ru-PTP-GCE) surface network were characterized using X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The apparent estimated value of electron transfer rate constant (k app) of the prepared sensor was three times greater than the virgin PTP. The cooperative effects of the (PTP) and Ru(II)-complex composite increased the efficiency and the stability of the proposed sensor for the selective determination of dopamine (DA) in the presence of ascorbic acid (AA) and uric acid (UA). The detection limit (DL3σ) of DA in this environment was 0.021 μM. The fabricated sensor was successfully applied for DA detection in a blood serum sample with satisfactory recovery.

Actualities in immunological markers and electrochemical sensors for determination of dopamine and its metabolites in psychotic disorders (Review).

Psychotic disorders represent a serious health concern. At this moment, anamnestic data, international criteria for diagnosis/classification from the Diagnostic and Statistical Manual of Mental Disorders-5 and the International Classification of Diseases-10 and diagnostic scales are used to establish a diagnosis. The most commonly used biomarkers in psychotic illnesses are those regarding the neuroimmune system, metabolic abnormalities, neurotrophins and neurotransmitter systems and proteomics. A current issue faced by clinicians is the lack of biomarkers to help develop a more accurate diagnosis, with the possibility of initiating the most effective treatment. The detection of biological markers for psychosis has the potential to contribute to improvements in its diagnosis, prognosis and treatment effectiveness. The mixture of multiple biomarkers may improve the ability to differentiate and classify these patients. In this sense, the aim of this study was to analyze the literature concerning the potential biomarkers that could be used in medical practice and to review the newest developments in electrochemical sensors used for dopamine detection, one of the most important exploited biomarkers.

Graphite paste electrodes modified with a sulfo-functionalized metal-organic framework (type MIL-101) for voltammetric sensing of dopamine.

The metal-organic frameworks MIL-101 and sulfo-MIL-101 were used to modify graphite paste electrodes (GPEs) to obtain sensors for determination of dopamine (DA). Taking advantage of the catalytic activity of metal-organic frameworks (MOFs) and of the electrical conductivity of graphite, the modified GPEs show enhanced voltammetric responses, and the GPE modified with the sulfo-MOF displays superior sensitivity when operated at a working potential of -0.4 to 0.8V (vs. Ag/AgCl). The sensor works in the 0.07 to100 μM DA concentration range and has a 43nM detection limit. It is concluded that the sulfo group provides open sites for efficient electrostatic and hydrogen bonding interactions, which facilitates electron transfer. Graphical abstractSchematic representation of the structure of the sulfo-functionalized MOF (sulfo-MIL-101) and the different voltammetric signals of dopamine at the graphite paste electrodes (GPEs) modified with sulfo-MIL-101 and the parent MOF (MIL-101).

Novel Design of a Layered Electrochemical Dopamine Sensor in Real Samples Based on Gold Nanoparticles/β-Cyclodextrin/Nafion-Modified Gold Electrode.

Change in the level of dopamine (DA) concentration in the human body causes critical diseases such as schizophrenia and Parkinson’s disease. Therefore, the determination of DA concentration and monitoring its level in human body fluids is of great importance. An electrochemical sensor based on modification of the gold electrode surface with Nafion (NF), β-cyclodextrin (CD), and gold nanoparticles (AuNPs) was fabricated for the determination of DA in biological fluids. Combined impact of all the modifiers enhances the catalytic activity of the sensor. Gold nanoparticles increase the surface area of the sensor and enhance the electron transfer rate. CD plays a main role in enhancing the accumulation of protonated DA and forming stable complexes via electrostatic interactions and hydrogen bond formation. In addition, extra preconcentration of positively charged DA is achieved through ionic selectivity of NF. High electrocatalytic activity was achieved using the modified sensor for determination of DA in real urine samples in a wide concentration range, 0.05–280 μM with a low detection limit of 0.6 nM in the small linear dynamic range, 0.05–20 μM. Furthermore, common overlapped oxidation peaks of DA in presence of biologically interfering compounds at the gold electrode were resolved by using the modified sensor. Excellent recovery results were obtained using the proposed method for determination of DA in real urine samples.

Graphene Modified Molecular Imprinting Electrochemical Sensor for Determining the Content of Dopamine

Background: The unnatural levels of dopamine (DA) result in serious neurological disorders such as Parkinson’s disease. Electrochemical methods which have the obvious advantages of simple operation and low-cost instrumentation were widely used for determination of DA. In order to improve the measurement performance of the electrochemical sensor, molecular imprinting technique and graphene have always been employed to increase the selectivity and sensitivity. Methods: An electrochemical sensor which has specific selectivity to (DA) was proposed based on the combination of a molecular imprinting polymer (MIP) with a graphene (GR) modified gold electrode. The performance and effect of MIP film were investigated by differential pulse voltammetry (DPV) and cyclic voltammetry (CV) in the solution of 5.0 ×10-3 mol/L K3[Fe(CN)6] and K4[Fe(CN)6] with 0.2 mol/L KCl at room temperature. Results: This fabricated sensor has well repeatability and stability, and was used to determine the dopamine of urine. Under the optimized experiment conditions, the current response of the imprinted sensor was linear to the concentration of dopamine in the range of 1.0×10-7 ~ 1.0×10-5 mol/L, the linear equation was I (µA) = 7.9824+2.7210lgc (mol/L) with the detection limit of 3.3×10-8 mol/L. Conclusion: In this work, a highly efficient sensor for determination of DA was prepared with good sensitivity by GR and great selectivity of high special recognization ability by molecular imprinting membrane. This proposed sensor was used to determine the dopamine in human urine successfully.

Differential pulse voltammetric determination of dopamine using Pd nanoparticles deposited on (3-aminopropyl)triethoxysilane functionalized CeO 2 nanoparticles

In this study, a novel and effective electrochemical sensor for determination of dopamine (DA) was successfully developed by the modification of a glassy carbon electrode (GCE) using Pd nanoparticles deposited on (3-aminopropyl)triethoxysilane functionalized nanoceria (Pd@CeO$_{2}$-APTES) and nafion used as a protective membrane. The synthesized nanocomposites were evaluated using X-ray diffraction, high-resolution transmission electron microscopy, and Fourier transform infrared spectroscopy. Moreover, the electrochemical properties of the modified electrodes were investigated using cyclic voltammetry, electrochemical impedance voltammetry, and differential pulse voltammetry (DPV). The Nf/Pd@CeO$_{2}$-APTES/GCE showed a linear range of 2.5--149.5 $\mu $M for DA by DPV with a notable sensitivity of 3.89 mA mM$^{-1\, }$cm$^{-2}$ and a low limit of detection of 0.46 $\mu $M based on the signal-to-noise ratio of 3 (S/N = 3). In addition, the sensor exhibited satisfactory selectivity, remarkable sensitivity, repeatability, and reproducibility. The sensor protected 92.07{\%} of its initial electrocatalytic activity toward the oxidation of dopamine after 30 days. The Nf/Pd@CeO$_{2}$-APTES/GCE was used for determination of DA in serum samples. The results indicate that the sensor can be a notable device for the detection of DA in biological fluids.

A Simple but Highly Sensitive and Selective Electrochemical Sensor for Determination of Dopamine Based on Langmuir-Blodgett Film of Calix[4]resorcinarene

In this work, a new electrochemical sensor was structured based on calix[4]resorcinarene LB film modified glassy carbon electrode (GCE) and used for sensitive determination of dopamine (DA). This new sensor displayed a significant response to DA from the synergetic effect of calix[4]resorcinarene LB film (high supramolecular recognition and enrichment capability) and electrochemically pretreated GCE (large surface area and high active sites). Moreover, the response of DA at this sensor was not interfered by the coexistence of ascorbic acid (AA) and uric acid (UA). Under the selective conditions, the response currents were linear relationship with DA concentrations in range of 5.0 × 10−8 – 1.0 × 10−5 mol L−1 with a limit of detection of 1.5 × 10−8 mol L−1 and a limit of Quantity of 5.0 × 10−8 mol L−1. At the same time, the new sensor showed good stability, selectivity and reproducibility.

A novel sensor for determination of dopamine in meat based on ZnO-decorated reduced graphene oxide composites

Abstract A novel electrochemical sensor based on the Zinc oxide (ZnO)-decorated reduced graphene oxide (RGO) composites was developed for determination of dopamine (DA) in meat. ZnO-decorated RGO (ZnO−RGO) composites were synthesized by a simple hydrothermal method, and characterized by scanning electron microscopy (SEM) images, Raman spectra, energy dispersive spectra (EDS) and X-ray diffraction (XRD) patterns. Electrochemical performance of the composites was studied by co-immobilization onto the surface of glassy carbon electrodes (GCE), which showed both high sensitivity and selectivity for detection of DA. Two linear ranges were obtained from 0.1 to 100 μM and 200 to 1800 μM, respectively. The detection limit (S/N ratio 3.0) was found to be 0.063 μM. Lastly, the proposed sensor was used for determination of DA in meat samples, which exhibited acceptable detection accuracy of greater than 90.18%. Thus, the proposed sensor may provide a promising alternative method for determination of DA in meats. Industrial relevance China is the world's biggest market for meat in terms of production as well as consumption, and the safety of meat has become a major problem for consumers. Dopamine (DA) is one kind of widespread ‘lean meat powder’ added to animal feed to help stocks build muscle rather than fat as an adrenergic neural stimulant. Use of DA in animal feed has been banned in most countries, and it is essential to prevent its illegal use. It is well known that abnormal levels of DA have been linked with Parkinson's disease, epilepsy, senile dementia and schizophrenia. Therefore, detecting the presence of DA in meat samples becomes a subject of great importance. In the study, the proposed ZnO-RGO composites modified GCE showed high sensitivity, excellent selectivity, wide concentration and good stability in the presence of AA, 5-HT and UA, including in real meat sample analysis. Results show that the proposed sensor has great potential in low-cost and convenient determination of DA in meat samples.

Sensitive and Selective Determination of Dopamine at a Nanocomposite Modified Sensor

A sensitive electrochemical sensor for determination of dopamine has been developed by modification of carbon paste electrode (CPE) with graphene (GRP), chitosan (CHIT) and zirconium oxide (ZrO2) nanoparticles. The morphological characteristics of nanocomposite (GRP-CHIT-ZrO2) were studied by scanning electron microscope and atomic force microscopy. Electrochemical characterization of the modified sensor was done using cyclic voltammetry and electrochemical impedance spectroscopy. Enhancement in electron transfer process and reduction in charge transfer resistance was observed. Electrochemical behavior of dopamine at nanocomposite modified CPE (GRP-CHIT-ZrO2/CPE) was investigated in pH 7.4 phosphate buffer solution using cyclic voltammetry and square wave voltammetry. The modified sensor showed enhancement in current response as compared to bare CPE. The modified sensor showed a linear response for dopamine in the range 1000 to 5000 nM. The limit of detection and limit of quantification were found to be 20 and 67 nM respectively which is lower than many other sensors reported for dopamine in literature. The modified sensor showed high sensitivity (2.23 nA/nM) and selectivity for determination of dopamine. The method was also successfully employed for determination of dopamine in human blood serum samples.

Electrochemical activation of polyethyleneimine-wrapped carbon nanotubes/in situ formed gold nanoparticles functionalised nanocomposite sensor for high sensitive and selective determination of dopamine

An electrochemical sensor based on polyethyleneimine (PEI)–multiwalled carbon nanotubes (MWNTs)–gold nanoparticles (AuNPs) nanocomposite was constructed for determination of dopamine (DA). MWNTs–PEI–AuNPs nanocomposite combined the advantages of PEI-well dispersed MWNTs and in situ formed AuNPs, thus endowed with high stability and some special properties to the enzyme-free sensor. The formation of the material was characterized by scanning electron microscope, transmission electron microscope and energy-dispersive X-ray. Electrochemical activation of the modified sensor at a positive potential remarkably enhanced the signal due to some introduced fragmentation in the side wall of MWNTs–PEI–AuNPs. Another important conclusion which was not recognized before is that CVD–CNT with open end caps of CNT also can be electrochemically activated after coating with polyelectrolytes (PEs). The prepared sensor showed good performance for the determination of DA in a linear range from 50 to 4000nM with a limit of detection of 6.56nM and a sensitivity of 5.2μAμM−1. It also exhibit high stability of at least 2months and high selectivity of DA under the interferences of glucose, ascorbic acid, etc. due to the novel sensing materials and remarkable electrochemical activation. We also demonstrated the successful application of this sensor for the determination of dopamine in serum.

Highly sensitive and selective dopamine biosensor based on 3,4,9,10-perylene tetracarboxylic acid functionalized graphene sheets/multi-wall carbon nanotubes/ionic liquid composite film modified electrode

A sensitive and selective electrochemical sensor for determination of dopamine (DA) was fabricated based on 3,4,9,10-perylene tetracarboxylic acid functionalized graphene sheets, multi-wall carbon nanotubes and ionic liquid modified glass carbon electrode and the properties of modified electrode were characterized by scanning electron microscopy, transmission electron microscope and electrochemical impedance spectroscopy. The modified electrode showed excellent electrocatalytic activity toward the oxidation of DA. Meanwhile, a possible reaction mechanism related to the oxidation of DA was proposed. The differential pulse voltammetry was used for the determination of DA in the presence of 500μM ascorbic acid and 330μM uric acid under the optimum conditions and a good linear relationship between peak current and the concentration of DA was obtained in the concentration range from 0.03μM to 3.82mM with a detection limit of 1.2×10−9M (S/N=3). Moreover, the proposed method was successfully applied to determine DA in real sample and satisfactory results were obtained. The results showed that the modified electrode exhibits an excellent catalytic activity, good sensitivity, reproducibility and long-term stability.

A novel electrochemical sensor for determination of dopamine based on AuNPs@SiO2 core-shell imprinted composite

A novel core-shell composite of gold nanoparticles (AuNPs) and SiO2 molecularly imprinted polymers (AuNPs@SiO2-MIPs) was synthesized through sol–gel technique and applied as a molecular recognition element to construct an electrochemical sensor for determination of dopamine (DA). Compared with previous imprinting recognition, the main advantages of this strategy lie in the introduction and combination of AuNPs and biocompatible porous sol–gel material (SiO2). The template molecules (DA) were firstly adsorbed at the AuNPs surface due to their excellent affinity, and subsequently they were further assembled onto the polymer membrane through hydrogen bonds and π–π interactions formed between template molecules and silane monomers. Cyclic voltammetry (CV) was carried out to extract DA molecules from the imprinted membrane, and as a result, DA could be rapidly and effectively removed. The AuNPs@SiO2-MIPs was characterized by ultraviolet visible (UV–vis) absorbance spectroscopy, transmission electron microscope (TEM) and Fourier transform infrared spectrometer (FT-IR). The prepared AuNPs@SiO2-MIPs sensor exhibited not only high selectivity toward DA in comparison to other interferents, but also a wide linear range over DA concentration from 4.8×10−8 to 5.0×10−5M with a detection limit of 2.0×10−8M (S/N=3). Moreover, the new electrochemical sensor was successfully applied to the DA detection in dopamine hydrochloride injection and human urine sample, which proved that it was a versatile sensing tool for the selective detection of DA in real samples.

Glassy carbon electrode modified with poly(dibromofluorescein) for the selective determination of dopamine and uric acid in the presence of ascorbic acid

We are presenting an electrochemical sensor for the simultaneous determination of dopamine (DA) and uric acid (UA) in the presence of even high concentrations of ascorbic acid (AA). It based on a glassy carbon electrode modified with an electroactive film of polymerized dibromofluorescein. The electrochemical behaviors of DA and UA were studied by cyclic voltammetry using the modified electrode. It exhibits excellent electrocatalytic activity towards the oxidation of the two analytes. Most notably, the oxidation potentials differ by 180 and 200 mV between AA-DA and DA-UA, respectively. Thus, excellent selectivity towards the oxidation of DA and UA in the presence of even high concentrations of AA is accomplished. Under the optimum conditions, the anodic peak currents are linearly related to the concentrations of DA and UA in the range from 0.2 to 200 μmol L-1 and from 1.0 to 250 μmol L-1, respectively. The detection limits for DA and UA are 0.03 μmol L-1 and 0.2 μmol L-1, respectively (at an S/N of 3). The method has good selectivity and sensitivity and was successfully applied to the simultaneous determination of DA and UA in spiked human serum.

A novel N,N′-[1,1′-Dithiobis(phenyl)] bis(salicylaldimine) self-assembled gold electrode for determination of dopamine in the presence of high concentration of ascorbic acid

N,N′-[1,1′-Dithiobis(phenyl)] bis(salicylaldimine) (DTPS) self-assembled monolayer has been fabricated on a bare gold electrode (Au electrode) as a novel sensor for determination of dopamine. The characterization of Au DTPS self-assembled monolayer modified electrode (DTPS SAM-ME) was investigated by cyclic voltammetry and ac impedance spectroscopy using the [Fe(CN)6]−3/−4 redox couple. The electroanalytical determination of dopamine was carried out in pH 6.0 0.1molL−1 phosphate buffer solution using differential pulse voltammetry. The diffusion coefficient of dopamine was calculated by chronocoulometry in pH 6.0 phosphate buffer solution to be 6.6×10−5cm2s−1. A calibration curve was obtained for dopamine in a linear range of 8.0×10−7 to 1.3×10−4molL−1 in the presence of high concentration of ascorbic acid. Selective detection was realized in elimination of ascorbic acid response on the DTPS SAM-ME. The detection limit for dopamine was found to be 3.0×10−8molL−1. The modified electrode showed acceptable selectivity, stability and anti-fouling properties. The results indicated that the DTPS SAM-ME could be employed for the determination of dopamine in pharmaceutical formulations and plasma samples. The lack of a voltammetric response for the oxidation of uric acid demonstrated that the human urine could be used for dopamine recovery tests with adequate selectivity and precision.

Gold Electrode Incorporating Corrole as an Ion-Channel Mimetic Sensor for Determination of Dopamine

Here, we report on an ion-channel mimetic sensor using self-assembly monolayers deposited onto gold electrodes for electrochemical determination of dopamine. The different compositions of the modification solution consist of corrole-SH and other thiol derivatives used as the "background compounds" such as 1-dodecanethiol (DDT), 6-mercapto-1-hexanol (HS(CH(2))(6)OH), or 11-mercapto-1-undecanol (HS(CH(2))(11)OH) were explored to find the best self-assembled monolayer (SAM) suitable for dopamine determination. Among them, the mixed SAM consisting of corroles with the -SH group and 6-mercapto-1-hexanol (HS(CH(2))(6)OH) in the molar ratio 1:10 was the most sensitive. The signals generated by the formation of a complex between the corrole host and the dopamine guest were measured by Osteryoung square-wave voltammetry (OSWV) and electrochemical impedance spectroscopy (EIS) with [Ru(NH(3))(6)](3+) as an electroactive marker. The developed sensor was free of interferences of components of human plasma such as ascorbic acid, creatinine, creatine, and uric acid. The detection limits observed by EIS in buffer solution and in the presence of centrifuged human plasma 80 times diluted with a 0.9% NaCl containing 0.01 M borate buffer solution of pH 7.0 were 3.3 x 10(-12) and 5.3 x 10(-12) M, respectively.