Detection Of Dopamine Research Articles

Fiber Optic SPR Sensor Modified With Copper Oxide Nanoparticles for Highly Sensitive and Selective Detection of Dopamine

Fiber Optic SPR Sensor Modified With Copper Oxide Nanoparticles for Highly Sensitive and Selective Detection of Dopamine

Porous gold-layered cubic and octahedral Cu-oxide nanocrystals: Dopamine sensing

Two morphologically different porous gold layered on Cu-oxide-based electrochemical sensors were developed for the selective detection of dopamine in the presence of uric acid, ascorbic acid or dextrose. The nanoparticles were prepared by layering Au onto either a cubic or octahedron-shaped Cu-oxide crystal via a galvanic reaction. These were characterized with scanning electron microscopy, energy dispersive X-ray and X-ray photoelectron spectroscopy. The porous structure of the gold over layer was clearly visible on the scanning electron microscopy image while the macro morphology was maintained. X-ray photoelectron spectroscopy confirmed the presence of metallic gold while both CuI (CuO) and CuII (Cu2O) were present in the samples. These two Au/Cu-oxide nanocomposites were used to modify glassy carbon electrodes and were tested for their dopamine sensing ability. Differential pulse voltammetry was used to investigate the selectivity towards dopamine in the presence of different interfering molecules uric acid, ascorbic acid and dextrose). From the differential pulse voltammetry, the lowest limit of detection was found to be 1.1 μM, with a sensitivity of 3.4 μA mM−1 mm−2 in the linear range of 10–250 μM for the porous gold layered covering the octahedron Cu-oxide-modified glassy carbon electrode.

Non-enzymatic electrochemical voltammetric sensors based on thulium:zinc oxide for dopamine detection

In this study, zinc oxide (ZnO) powders with dopant rates of 1 mol% thulium (Tm) (1Tm:ZnO), 2 mol% Tm (2Tm:ZnO), and 3 mol% Tm (3Tm:ZnO) nanoparticles were synthesized by co-precipitation method. Subsequently, Polyaniline (PANI)/1Tm:ZnO, PANI/2Tm:ZnO, and PANI/3Tm:ZnO nanocomposite sensors were prepared using a low-cost and simple sonication method. The results showed that the prepared PANI/1Tm:ZnO-based biosensor detected dopamine in the concentration range of (0.8–6.5) µM with a sensitivity of 0.2568 µAµM−1cm−2. Using these sensitivity values of the sensor, the LOD and LOQ values of the PANI/1Tm:ZnO-based sensor were calculated as 1.92 µM and 5.8 µM, respectively. The incorporation of 1% Tm into ZnO host (PANI/1Tm:ZnO) significantly enhanced the sensitivity of the biosensors.

Biocompatible Folic-Acid-Strengthened Ag-Ir Quantum Dot Nanozyme for Cell and Plant Root Imaging of Cysteine/Stress and Multichannel Monitoring of Hg2+ and Dopamine.

To boost the enzyme-like activity, biological compatibility, and antiaggregation effect of noble-metal-based nanozymes, folic-acid-strengthened Ag-Ir quantum dots (FA@Ag-Ir QDs) were developed. Not only did FA@Ag-Ir QDs exhibit excellent synergistic-enhancement peroxidase-like activity, high stability, and low toxicity, but they could also promote the lateral root propagation of Arabidopsis thaliana. Especially, ultratrace cysteine or Hg2+ could exclusively strengthen or deteriorate the inherent fluorescence property with an obvious "turn-on" or "turn-off" effect, and dopamine could alter the peroxidase-like activity with a clear hypochromic effect from blue to colorless. Under optimized conditions, FA@Ag-Ir QDs were successfully applied for the turn-on fluorescence imaging of cysteine or the stress response in cells and plant roots, the turn-off fluorescence monitoring of toxic Hg2+, or the visual detection of dopamine in aqueous, beverage, serum, or medical samples with low detection limits and satisfactory recoveries. The selective recognition mechanisms for FA@Ag-Ir QDs toward cysteine, Hg2+, and dopamine were illustrated. This work will offer insights into constructing some efficient nanozyme sensors for multichannel environmental analyses, especially for the prediagnosis of cysteine-related diseases or stress responses in organisms.

Transplantation of human neural stem cell prevents symptomatic motor behavior disability in a rat model of Parkinson's disease.

Parkinson's disease (PD) is a ubiquitous brain cell degeneration disease and presents a significant therapeutic challenge. By injecting 6-hydroxydopamine (6-OHDA) into the left medial forebrain bundle, rats were made to exhibit PD-like symptoms and treated by intranasal administration of a low-dose (2 × 105) or high-dose (1 × 106) human neural stem cells (hNSCs). Apomorphine-induced rotation test, stepping test, and open field test were implemented to evaluate the motor behavior and high-performance liquid chromatography was carried out to detect dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC), serotonin, and 5-hydroxyindole-3-acetic acid in the striatum of rats. Animals injected with 6-OHDA showed significant motor function deficits and damaged dopaminergic system compared to the control group, which can be restored by hNSCs treatment. Treatment with hNSCs significantly increased the tyrosine hydroxylase-immunoreactive cell count in the substantia nigra of PD animals. Moreover, the levels of neurotransmitters exhibited a significant decline in the striatum tissue of animals injected with 6-OHDA when compared to that of the control group. However, transplantation of hNSCs significantly elevated the concentration of DA and DOPAC in the injured side of the striatum. Our study offered experimental evidence to support prospects of hNSCs for clinical application as a cell-based therapy for PD.

Ultrafine FeCuAgCeGd–based high–entropy nanozyme: Preparation, catalytic mechanism, and point–of–care detection of dopamine in human serum

Point–of–care testing (POCT) plays vital role in clinic field, especially in resource–limited areas. The nanozyme–based colorimetric platform is the potential strategy for POCT. Therefore, a high–entropy allay nanozyme (HEAzyme) was prepared via formaldehyde–assisted metal–ligand crosslinking method using multi–metal (FeCuAgCeGd) species. The obtained FeCuAgCeGd–HEAzyme showed coordination nanoparticles with ultrafine size (average size was approximately 5 nm). The peroxidase–like (POD–like) activity of FeCuAgCeGd–HEAzyme was verified through density functional theory (DFT) calculations, demonstrating the capability of FeCuAgCeGd–HEAzyme to catalyze H2O2 and generate hydroxyl radicals (•OH). These radicals can oxidize colorless 3,3′,5,5′–tetramethylbenzidine (TMB) to blue oxTMB. Dopamine (DA) scavenges •OH, resulting in an “on–off” effect for TMB oxidation. Subsequently, an FeCuAgCeGd–HEAzyme colorimetric sensor was developed for DA detection, which features a low detection limit of 0.77 µM and a linear range of 5.0–70.0 µM. The sensor demonstrated a recovery ratio in spiked serum samples ranging from 97.7 % to 104.3 % with high stability and favorable selectivity. Furthermore, an FeCuAgCeGd–HEAzyme POCT platform was designed for on–site detection of DA, achieving a reliable linear detection range (5.0–70.0 µM) and a low detection limit (5.69 µM). This platform offers a facile and efficient strategy for rapid, visual, and on–site DA detection in clinical settings with advantages of cost–effectiveness and ease of operation.

Aptamer-enhanced organic electrochemical transistors for ultra-sensitive dopamine detection

In this study, we present the development of an ultrasensitive dopamine (DA) aptasensor based on organic electrochemical transistors (OECTs). The aptasensor utilizes a highly efficient DA aptamer immobilized on the surface of a gold gate electrode in the OECT. The functionalization of the aptamer was confirmed through fluorescence intensity measurements and transfer characteristics of the OECT device. Real-time detection of DA was achieved, and the sensor exhibited a linear response in the concentration range of 10 fM to 10 nM, with a detection limit of 10 fM. The aptasensor's working mechanism was elucidated, involving mutual binding between DA and the aptamer that leads to a shift in the transfer characteristics. Our aptasensor shows great promise for sensitive and rapid detection of DA, which is crucial in diagnosing neurological disorders such as Parkinson's and Alzheimer's diseases. The combination of OECTs and aptamer-based recognition elements offers a cost-effective and efficient platform for detecting biomolecules like DA in various clinical applications.

Electrochemical Detection of Dopamine at a Novel Poly(2,4,6‐trihydroxybenzaldehyde) Film Modified Electrode

AbstractIn this study, a novel electrodeposition of poly(2,4,6‐trihydroxybenzaldehyde) on bare glassy carbon electrode for dopamine detection was reported. 2,4,6‐trihydroxybenzaldehyde and the electrodeposited poly(2,4,6‐trihydroxybenzaldehyde) were characterized using Fourier transform‐infrared spectroscopy, UV‐visible spectroscopy, and scanning electron microscopy. The bare electrode modified with the optimum amount of 2,4,6‐trihydroxybenzaldehyde (PTGCE) was used for dopamine electroanalysis. The linear dynamic range and the limit of detection of DA at PTGCE were 0.70‐19.48 μM and 19.48–53.30 μM, and 0.64 μM, respectively. The modified electrode showed outstanding discriminatory dopamine detection in the presence of uric acid and ascorbic acid due to a dopamine‐uric acid and a dopamine‐ascorbic acid peak‐to‐peak separation of 160 mV and 200 mV, respectively. The proposed sensor showed considerable reproducibility of dopamine current response and excellent % dopamine recovery of 99.70 % from the real sample solution.

Straightforward method for the electrochemical identification of dopamine in the presence of uric acid and ascorbic acid

A few-layer graphene/Pt (FGP) electrode and a novel electrochemical technique were used in determining dopamine and simultaneously detecting uric acid (UA), ascorbic acid (AA), and dopamine (DA) in a buffered phosphate-saline solution at pH 7.4. The FGP electrode effectively separated the oxidation peaks of UA, DA, and AA in the positive scan. Interestingly, during the negative scan, the FGP electrode selectively responded to DA while showing negligible response to UA and AA, thus allowing the accurate quantification of small amounts of DA in the presence of considerable UA and AA interferences. The sensors for AA, DA, and UA exhibited successful detection in the positive scan. The linear ranges were 10–1800 (AA), 1–300 (DA), and 5–800 (UA) µM, the sensitivity was 109.27 (AA), 754.19 (DA), and 493.03 (UA) µA cm–2 mM–1, and the detection limits were 4.2 µM (AA), 0.42 µM (DA), and 2.2 µM (UA). Furthermore, DA quantification was achieved in the negative scan, demonstrating a linear range of 1–100 µM, sensitivity of 2235.7 µA cm–2 mM–1, and detection limit of 0.14 µM. This study presents a novel and efficient electrochemical technique for the rapid and straightforward detection of dopamine.

Simultaneous electrochemical detection of dopamine and uric acid based on tri-composite of poly-pyrrole and α-Fe2O3 embedded MoS2 sheets modified electrode

Poly-pyrrole (Ppy) with α-Fe2O3 and MoS2 has served as an attractive catalyst for biosensor applications due to their versatility and structural diversity. The abnormal concentrations of dopamine (DA) and uric acid (UA) causes serious health issues in human. Hence, rapid and sensitive method requires to monitor DA and UA levels. In this esteem, a electrochemical biosensor based on Ppy-α-Fe2O3-MoS2 composite for rapid and accurate estimation of DA and UA in physiological conditions were reported. The ternary components like Ppy, MoS2 sheets, and α-Fe2O3 attribute the heterogeneous interfacial contact which leads to enhanced catalytic behavior. The Ppy-α-Fe2O3-MoS2/GCE electrocatalyst demonstrates the linear response of DA, and UA in the concentration range of 300 nM-1 mM with a detection limit of 73 nM, and 61 nM for DA and UA, respectively (S/N = 3σ/n). The sensitivity of the sensor was found to be 1.26 μA μM−1 cm2.The proposed methodology is highly selective, sensitive and cheaper to detect the DA and UA simultaneously. This approach could be utilized to employ in the fabrication of biosensor devices for practical utility in clinical diagnostics and health care centers.

Ultrasensitive detecting of dopamine in complex components by field effect transistor sensor based on the synergistic enhancement effect and overcoming debye length limitations

Field effect transistor (FET) has attracted high attention in biomolecules detection. However, the sensitivity of FET-based biosensors is often limited by the charge screening effect. In addition, the facile and ultra-sensitive detection for small biomolecules, which possess weak charge or electroneutral, remains to be studied. Here, the self-assembled monolayer AuNPs/three-dimensional (3D) crumpled graphene FET is structured for a biosensor by shrinking flexible polystyrene (PS) films through heat treatment method and realized label-free and ultra-sensitive detection of dopamine (DA) using DA aptamer as probes immobilized on the AuNPs/3D crumpled graphene surface. The nanoscale deformation caused by thermal expansion effect of flexible graphene/PS can effectively reduce charge screening and the synergistic application of crumpled graphene and AuNPs can promote electron transfer and the graphene carrier concentration, leading to conductivity increase and hydrophilicity enhancement of 3D graphene. In addition, the binding of DA aptamer to DA will cause conformational changes of the aptamer molecule, which affects the charge transport properties of the sensor, thus improving its selectivity and stability. The biosensor can also easily distinguish interfering substances for DA detection in complex components (PBS, human urine, and fetal calf serum) with the detection limits as low as 60, 240 and 316 zM (10−19–10−11 M), respectively. DA released from exocytosis induced by K+ stimulation was selectively detected. The results show that the biosensor can be used as an excellent tool for ultrasensitive molecular recognition and detecting the effects of exogenous reagents on living cells, which is promising for clinical diagnosis and early disease prevention.

Electrochemical synthesis of polypyrrole composite with modified gold nanoparticles for electrochemical detection of ascorbic acid, dopamine and acetaminophen in different pharmaceutical samples

Electrochemical synthesis of polypyrrole composite with modified gold nanoparticles for electrochemical detection of ascorbic acid, dopamine and acetaminophen in different pharmaceutical samples

Carbon Quantum Dot Embedding Silica–Molecularly Imprinted Polymer Coated Optical Fiber as Ratiometric Biosensors Toward Dopamine Detection

Carbon Quantum Dot Embedding Silica–Molecularly Imprinted Polymer Coated Optical Fiber as Ratiometric Biosensors Toward Dopamine Detection

Three-dimensional carbon interdigitated ring array nanofibers for electrochemical detection of dopamine neurotransmitter

Dopamine (DA) neurotransmitter is a prominent component of the central nervous system and its deficiency contributes to several diseases, such as Parkinson’s disease and schizophrenia, which significantly influence the quality of life of affected individuals. This paper introduces a circular interdigitated ring electrode, the three-dimensional carbon interdigitated ring array nanofibers (3D C-IDRA NFs), for the detection of DA using amperometric detection. The study utilized cyclic voltammetry and chronoamperometry to investigate DA. The integration of carbon nanofibers (CNFs) with 3D C-IDRA demonstrated enhanced surface area, increased current peak, and superior performance compared to the standalone 3D C-IDRA electrode, as evidenced by a redox amplification factor of 2.94 and a collection efficiency of 81.1%. The results highlight that integrating CNFs with 3D C-IDRA improves the electrochemical performance in detecting DA neurotransmitter. Thus, this discovery elucidates the advantageous potential of the 3D C-IDRA NF electrode in a wide range of applications.

Quantification of Plasma Dopamine in Depressed Patients Using Silver-Enriched Silicon Nanowires as SERS-Active Substrates.

A decrease in the levels of dopamine (DA)─a key catecholamine biomarker for major depressive disorder─highlights the need for quantitative analysis of biological fluids to aid in the early diagnosis of diverse neuropsychiatric disorders. This study developed silicon nanowires enriched with silver nanoparticles to serve as a surface-enhanced Raman scattering (SERS) substrate to enable precise and sensitive quantification of blood plasma DA levels in humans. The silver-enriched silicon nanowires (SiNWs@Ag) yielded flower-like assemblies with densely populated SERS "hot spots," allowing sensitive DA detection. By correlating DA concentration with Raman intensity at 1156 cm-1, the plasma DA levels in treatment-naïve patients with major depression (n = 18) were 2 orders of magnitude lower than those in healthy controls (n = 18) (6.56 × 10-10 M vs 1.43 × 10-8 M). The plasma DA concentrations differed significantly between the two groups (two-tailed p = 5.77×10-7), highlighting a distinct demarcation between depression patients and healthy controls. Furthermore, the SiNWs@Ag substrate effectively differentiated between DA and norepinephrine (NE) in mixtures at nanomolar levels, demonstrating its selective detection capability. This study represents the first report on the quantitative detection of DA levels in human blood samples from individuals with major depression using an SERS technique, emphasizing its potential clinical utility in the evaluation and diagnosis of neuropsychiatric disorders.

Electrochemical detection of dopamine by pineapple leaf‐derived porous carbon modified electrode

AbstractThis research established an electrochemical sensing platform for sensitive dopamine (DA) detection using a modified glassy carbon electrode (GCE) made from waste pineapple leaf derived porous carbon (PLPC), which was applied to DA analysis in human blood samples with the characteristics such as simple procedure, excellent anti‐interference ability and low detection limit. Transmission electron microscopy revealed a layered and porous structure in the morphology of PLPC. PLPC's specific surface area and average pore size were determined to be 350.48 m2/g and 3.72 nm, respectively. The crystal phase and valence state were examined using X‐ray photoelectron spectroscopy and X‐ray diffraction. Using the best parameters, cyclic voltammetry and differential pulse voltammetry were applied to study the electrochemical behaviors of DA on PLPC/GCE. On PLPC/GCE a wide linear range of 0.05–500.0 μmol/L and a low detection limit of 0.0075 μmol/L for DA detection could be realized. The recoveries of DA were 97.67–102.07 % for detection of human blood sample with excellent stability, reproducibility and repeatability. Therefore the waste pineapple leaf based biomass porous carbon could be used as promising potential candidate for sensing application.

Non-Enzyme, Temperature Calibrating, and Bioactive Fiber-based Flexible Sensors for Dopamine and Lactic Acid Detection

Non-Enzyme, Temperature Calibrating, and Bioactive Fiber-based Flexible Sensors for Dopamine and Lactic Acid Detection

Simultaneous detection of ascorbic acid, dopamine, acetaminophen and tryptophan using a screen-printed electrode modified with woolen ball-shaped La3+/TiO2 nanostructure as a quadruplet nanosensor

Woolen ball-shaped La3+/TiO2 nanostructure (WB-S La3+/TiO2-NS) was constructed, followed by specification using X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Cyclic voltammograms of this new nanocomposite sensor provided distinct and sharp oxidation peaks for the study analytes, including ascorbic acid (AA), dopamine (DA), acetaminophen (AC) and tryptophan (Try). An effective electron-mediated response of the nanosensor was determined with broad peak separations of 0.2 for AA-DA, 0.2 for DA-AC, and 0.31 V for AC-Try. According to differential pulse voltammograms, the nanostructure electrode could simultaneously detect AA, DA, AC and Try, with linear ranges from 0.001 to 900.0 μM, with the limit of detection of 0.63 ± 0.01, 0.51 ± 0.02, 0.72 ± 0.03 and 0.84 ± 0.04 nM, sequentially. Further, the analytical applicability of WB-S La3+/TiO2-NS/SPE was confirmed by sensing AA, DA, AC and Try in real human serum samples.

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.

Simultaneous Electrochemical Detection of Dopamine and Uric Acid via Au@Cu-Metal Organic Framework.

The incorporation of noble metals with metal-organic frameworks (MOFs) are conducive for simultaneous electrochemical detection of analytes owing to multiple accessible reaction sites. Herein, Au@Cu-metal organic framework (Au@Cu-MOF) is successfully synthesized and modified a screen-printed carbon electrode (SPCE), which serves as an excellent electrocatalyst for the oxidation of dopamine (DA) and uric acid (UA). The sensor shows a linear range from 10 μM to 1000 μM, with sensitivity and detection limit of 0.231 μA μM-1 cm-2 and 3.40 μM for DA, and 0.275 μA μM-1 cm-2 and 10.36 μM for UA. Au@Cu-MOF could realize the individual and simultaneous electrochemical sensing of DA and UA, with distinguishable oxidation peak potentials. Moreover, it exhibits reproducibility, repeatability, and stability. Ultimately, the sensor provides an avenue for an ultrasensitive label-free electrochemical detection of DA and UA.