Detection Of Dopamine Research Articles

ZnO-CeO2 Hollow Nanospheres for Selective Determination of Dopamine and Uric Acid

ZnO-CeO2 hollow nanospheres have been successfully synthesized via the hard templating method, in which CeO2 is used as the support skeleton to avoid ZnO agglomeration. The synthesized ZnO-CeO2 hollow nanospheres possess a large electrochemically active area and high electron transfer owing to the high specific surface area and synergistic effect of ZnO and CeO2. Due to the above advantages, the resulting ZnO-CeO2 hollow spheres display high sensitivities of 1122.86 μA mM−1 cm−2 and 908.53 μA mM−1 cm−2 under a neutral environment for the selective detection of dopamine and uric acid. The constructed electrochemical sensor shows excellent selectivity, stability and recovery for the selective analysis of dopamine and uric acid in actual samples. This study provides a valuable strategy for the synthesis of ZnO-CeO2 hollow nanospheres via the hard templating method as electrocatalysts for the selective detection of dopamine and uric acid.

Graphene derivative-based ink advances inkjet printing technology for fabrication of electrochemical sensors and biosensors

The field of biosensing would significantly benefit from a disruptive technology enabling flexible manufacturing of uniform electrodes. Inkjet printing holds promise for this, although realizing full electrode manufacturing with this technology remains challenging. We introduce a nitrogen-doped carboxylated graphene ink (NGA-ink) compatible with commercially available printing technologies. The water-based and additive-free NGA-ink was utilized to produce fully inkjet-printed electrodes (IPEs), which demonstrated successful electrochemical detection of the important neurotransmitter dopamine. The cost-effectiveness of NGA-ink combined with a total cost per electrode of $0.10 renders it a practical solution for customized electrode manufacturing. Furthermore, the high carboxyl group content of NGA-ink (13 wt%) presents opportunities for biomolecule immobilization, paving the way for the development of advanced state-of-the-art biosensors. This study highlights the potential of NGA inkjet-printed electrodes in revolutionizing sensor technology, offering an affordable, scalable alternative to conventional electrochemical systems.

A photoelectrochemical sensor based on In2O3/In2S3/ZnIn2S4 ternary Z-scheme heterojunction for ultrasensitive detection of dopamine in sweat.

A novel ternary heterojunction material In2O3/In2S3/ZnIn2S4 was synthesized, and a photoelectrochemical sensor was fabricated for the non-invasive test of dopamine (DA) in sweat. In2O3 multihollow microtubules were synthesized and then In2S3 was formed on their surface to construct a type-I heterojunction between In2S3 and In2O3. ZnIn2S4 was further introduced to form a Z-scheme heterojunction between In2S3/ZnIn2S4. Under photoexcitation, the photogenerated holes of In2O3 transferred to the valence band of In2S3, superimposed with the holes produced by In2S3, leads to a significantly higher photocatalytic oxidation capacity of In2O3/In2S3/ZnIn2S4 ternary composites than that of In2O3/In2S3. TheZ-scheme heterojunction accelerates the transfer of photogenerated electrons accumulated on the type-I heterojunction. In the presence of DA, itis rapidly oxidized into polydopamine (PDA) by In2O3/In2S3, and the benzoquinone groups of PDA compete for the photogenerated electrons to reduce the current in the external circuit, whereby DA determination is achieved. Owing to the combination of type-I and Z-scheme heterojunction, the sensor showed extremely high sensitivity, with a detection limit of 3.94 × 10-12 mol/L. It is one of the most sensitive methods for DA detection reported and has been applied to the determination of DA in human sweat.

Hydroxylase-like Biomimetic Nanozyme Synthesized via a Urea-Mediated MOF Pyrolytic Reconstruction Strategy for Non-"o-Phenol hydroxyl"-Dependent Dopamine Electrochemical Sensing.

Dopamine (DA), an essential neurotransmitter, is closely associated with various neurological disorders, whose real-time dynamic monitoring is significant for evaluating the physiological activities of neurons. Electrochemical sensing methods are commonly used to determine DA, but they mostly rely on the redox reaction of its o-phenolic hydroxyl group, which makes it difficult to distinguish it from substances with this group. Here, we design a biomimetic nanozyme inspired by the coordination structure of the copper-based active site of dopamine β-hydroxylase, which was successfully synthesized via a urea-mediated MOF pyrolysis reconstruction strategy. Experimental studies and theoretical calculations revealed that the nanozyme with Cu-N3 coordination could hydroxylate the carbon atom of the DA β-site at a suitable potential and that the active sites of this Cu-N3 structure have the lowest binding energy for the DA β-site. With this property, the new oxidation peak achieves the specific detection of DA rather than the traditional electrochemical signal of o-phenol hydroxyl redox, which would effectively differentiate it from neurotransmitters, such as norepinephrine and epinephrine. The sensor exhibited good monitoring capability in DA concentrations from 0.05 to 16.7 μM, and its limit of detection was 0.03 μM. Finally, the sensor enables the monitoring of DA released from living cells and can be used to quantitatively analyze the effect of polystyrene microplastics on the amount of DA released. The research provides a method for highly specific monitoring of DA and technical support for initial screening for neurocytotoxicity of pollutants.

Covalent organic frameworks surface-anchored with silver nanoparticles for colorimetric detection of dopamine based on its oxidase-mimicking activity

Sensitive detection of dopamine (DA) is essential for the diagnosis of nervous system diseases. Herein, a nanozyme-based colorimetric platform for DA determination was proposed. Using an imine-type covalent organic framework (COF-TD) as a host matrix, a nanozyme (AgNPs@COF-TD) was fabricated by anchoring silver nanoparticles (AgNPs) on the surface of COF-TD via in situ reduction of silver ions. Various characterization results confirmed the successful synthesis of flower-like AgNPs@COF-TD with surface-anchored AgNPs, which could expose more active sites. The as-prepared AgNPs@COF-TD exhibited satisfactory oxidase-mimicking activity with a low Km, which could catalyze the oxidation of colorless 3,3′,5,5′-tetramethylbenzidine (TMB) to blue oxidized TMB (oxTMB) with significant absorbance at 657 nm. The introduction of DA not only reduced blue oxTMB to colorless TMB but also competed with TMB for the active sites of AgNPs@COF-TD, making a significant decrease in absorbance. Therefore, a label-free sensing strategy based on the oxidase-mimicking activity of AgNPs@COF-TD was successfully established for the colorimetric detection of DA, with a detection limit down to 0.2 μM. The practical applicability of this assay was further validated by analyzing DA-spiked human urine samples. This work provided a facile approach to prepare COF-based nanozymes, and demonstrated their great potential in colorimetric detection and bioanalysis.

The Layer-by-Layer Assembled ERGO+/ERGO- Multilayer Modified Electrode for Sensitive Detection of Dopamine

Abstract Graphene materials represented by graphene oxide (GO) have been widely regarded as functional coatings or films to modify surface of the electrode for detecting dopamine molecules. However, interfacial material properties for detection sensitivity, film stability, and applicability to electrodes are still highly desired. Herein, we first present a screen-printing carbon electrode (SPCE) coated with an electrochemically reduced layer-by-layer (LbL) assembled multilayer driven by an electrostatic interaction between positively charged polyethyleneimine-modified GO with amine groups (ERGO+) and negatively charged carboxyl-functionalized GO (ERGO-), which is briefly described as (ERGO+/ERGO-)n/SPCE. Firstly, without using conventional glassy carbon and gold electrodes, SPCE was tried to make coatings adapt to more flexible and unstable electrodes, simultaneously guaranteeing higher detection performance. Secondly, although a variety of electrochemical sensors such as GO-/SPCE and ERGO-/SPCE were obtained through the drop-casting technique, as-prepared (ERGO+/ERGO-)n/SPCE showed much higher electrocatalytic activities with enhanced peak current signals and reduced charge transfer resistance. Finally, excellent electrochemical properties and sensing performances of the (ERGO+/ERGO-)n/SPCE sensor for detection of dopamine were demonstrated, especially having a linear range of 1 μM to 1000 μM. Meanwhile, the detection limit is as low as 0.39 μM and S/N is equal to 3. The present work offers a potential direction to develop GO modified electrodes for sensitive biomolecular detection.

Electrochemically selective detection of dopamine over serotonin by CuO/Cu2O bulk heterostructure electrode

Electrochemically selective detection of dopamine over serotonin by CuO/Cu2O bulk heterostructure electrode

BSA nanoclusters-based sensor for detection of dopamine in schizophrenia from biofluids

Objective To develop nontoxic and stable fluorescent emission B-Cu nanoclusters (NCs) for the specific detection of dopamine at low concentrations in cerebrospinal fluid (CSF). Significance Fluorescent gold and copper NCs conjugated with proteins, such as bovine serum albumin (BSA), offer photostability and healthcare potential. This study focused on fabricating B-Cu NCs that exhibited superior characteristics for sensitive dopamine detection. Methods The study employed various instrumental techniques including attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), spectrofluorometry, and transmission electron microscopy (TEM) to characterize the formulated B-Cu NCs. The NCs were synthesized, resulting in particle size ∼300 nm. The highest observed fluorescence was recorded at 24542.81 relative fluorescence units (RFU). Results The introduction of dopamine at concentrations of 0.1, 0.2, 0.3, and 0.4 ng/mL led to decreased fluorescence in both B-Au and B-Cu NCs due to an electron transport system. This reduction in fluorescence allowed dopamine concentration analysis in phosphate buffer and biological fluids such as blood plasma and CSF. B-Cu NCs showed potential as a biosensing system for point-of-care (POC) applications, specifically for diagnosing schizophrenia. Conclusion The study successfully synthesized stable and nontoxic B-Cu NCs with enhanced fluorescent emission properties. These NCs exhibited the capacity to detect dopamine at low concentrations in CSF. The study’s findings hold promise for future applications, particularly in the development of a B-Cu NCs-based biosensing system for convenient POC detection of schizophrenia by both patients and clinicians. The potential impact of this technology on healthcare and biomedical fields is substantial.

Design and Fabrication of NiMn Layered Double Hydroxide/Reduced Graphene Oxide as Electrochemical Sensor for Simultaneous Detection of Ascorbic Acid, Dopamine and Uric Acid

Design and Fabrication of NiMn Layered Double Hydroxide/Reduced Graphene Oxide as Electrochemical Sensor for Simultaneous Detection of Ascorbic Acid, Dopamine and Uric Acid

One-pot synthesis of cerium-organic framework@carbon black composites for simultaneous detection of dopamine, uric acid, and acetaminophen

Accurate identification of dopamine (DA), uric acid (UA), and acetaminophen (APAP) is critical to safeguarding human health. However, their simultaneous detection is still challenging due to their similar oxidation potentials. In this work, a series of new composites based on cerium-organic framework (Ce-MOF) and carbon black (CB) were constructed by one-pot method at room temperature. The introduction of CB can significantly affect the conductivity and specific surface area of the composites. The optimal composite Ce-MOF-COOH/CB0.4 can identify DA, UA, and APAP simultaneously with low detection limit of 0.030, 0.045, and 0.057 μM and wide detection range of 2.5–310.0, 3.0–305.0, and 2.5–617.0 μM, respectively. Furthermore, density-functional theory (DFT) calculation was performed to explore the influence of functional groups (-NH2 or –COOH) on the sensing performance. It was found that the introduced functional groups can obviously enhance the host-guest interactions through the formation of strong hydrogen bonds, which is beneficial for promoting sensing performance. In addition, the constructed electrode could also detect DA, UA, and APAP in real samples, which indicated its potential for practical applications. This study provides a feasible approach to utilize MOFs as electrochemical sensors for simultaneously detection of biomolecules.

Ratiometric fluorescence detection of dopamine based on copper nanoclusters and carbon dots

Nanoclusters for fluorescence detection are generally comprised of rare and expensive noble metals, and the nanoclusters based on more affordable transition metal have attracted increasing attention. This study designed a ratiometric fluorescent probe to detect dopamine (DA), an important neurotransmitter. With carbon dots encapsulated within silica (CDs@SiO2) as the reference, the emitted reference signal was almost unchanged due to the protection of inert silicon shell. Meanwhile, copper nanoclusters modified with 3-aminophenyl boronic acid (APBA-GSH-CuNCs) provided the sensing signal, in which the phenylboric acid could specifically recognize the cis-diol structure of DA, and caused the fluorescence quenching by photoinduced electron transfer. This dual emission ratiometric fluorescent probe exhibited high sensitivity and anti-interference, and was able to selectively responded to DA with a linear range of 0–1.4 mM, the detection limit of 5.6 nM, and the sensitivity of 815 mM−1. Furthermore, the probe successfully detected DA in human serum samples, yielding recoveries ranging from 92.5% to 102.7%. Overall, this study highlights the promising potential of this ratiometric probe for detecting DA.

In situ growth of BiVO4–Bi2O3 p-n heterojunction nanocomposite via facile green combustion method: Efficient photocatalytic activity under visible light, photoluminescence and biosensing applications

The easiest and simplest green combustion approach was successfully used to synthesize the pn Heterojunction BiVO4/Bi2O3 nanocomposites (NCs) with efficient visible light activity. Different stoichiometric ratios of butea monosperma leaf powder were used as the green fuel. Using XRD, SEM, EDAX, FTIR, UV–visible, and PL spectroscopy, the phase and surface structure, composition, and optical properties of synthesized NCs are characterised. In comparison to other ratios, it was found that the 1:1.5 ratio of BiVO4/Bi2O3 NCs exhibits good photocatalytic performance for the degradation of rose bengal dye. The outcome demonstrated that the formation of a p-n heterojunction between p-type Bi2O3 and n-type BiVO4 is responsible for the improved photocatalytic activity. It resulted from the separation of electron and hole pairs and the improvement of the interfacial charge transfer efficiency, both of which were made possible by the heterojunction. In addition, the BVO 15 photocatalyst exhibits good stability across 4 degradation cycles. The glassy carbon electrode (GCE) was modified with BVO NCs for the electrochemical detection of dopamine (DA). By using CV and LSV, the electrochemical behaviour of the fabricated electrode was examined. The outcomes demonstrate that BVO NCs have strong electrocatalytic activity. The limit of detection (LOD) was determined to be 33 μM. The current work is also a beneficial effort for developing new visible light photocatalysts with heterojunction architectures and biosensors.

One-drop micro-array towards accelerated optical quantification of dopamine in human biofluids using triangular silver nanoparticles: Smartphone-assisted biomedical analysis by colorimetric sensing and Lab-on-paper technology

Trace-level detection of Dopamine (DA) in human body fluids is crucial for diagnosing neurological disorders, understanding mental health, and advancing drug discovery, but found challenging with rapid and low-cost detection technologies. Herein, an innovative paper-based photochemical method has been developed for the detection of DA using triangular silver nanoprism (AgNPrs), as an optical nanoprobe, in human blood plasma and urine samples. The redox reaction between DA and AgNPrs was evaluated through a color change at two pHs (5.35and 6.14), which can be analyzed by UV–Vis spectrophotometry and microfluidic paper-based colorimetric device (µPCD) with low limit of quantification of 0.01 µM. This study presents pioneering work with the potential to inspire the development of simple and effective on-site semi quantifying recognition devices for other neurotransmitters, requiring only a lightweight piece of paper and a single drop of the necessary reagent.

Construction of an ECL-DPV Dual Model Biosensor for Dopamine Detection Based on PSO-ANN Algorithm

Construction of an ECL-DPV Dual Model Biosensor for Dopamine Detection Based on PSO-ANN Algorithm

Reusable graphite-based electrochemical sensors for L-dopa and dopamine detection.

Afully reusable electrochemical device is proposed for the first timemade from laser cutting and a homemade conductive ink composed of carbon and nail polish. As a sensor substrate, we applied polymethyl methacrylate, which allows the surface to be renewed by simply removing and reapplying a new layer of ink. In addition to the ease of renewing the sensor's conductive surface, the design of the device has allowed for the integration of different forms of analysis. The determination of L-Dopa was performed using DPV, which presented a linear response range between 5.0 and 1000.0μmol L-1, and a LOD of 0.11μmol L-1. For dopamine, a flow injection analysis system was employed, and using the amperometric technique measurements were performed with a linear ranging from 2.0 to 100.0μmol L-1anda LOD of 0.26μmol L-1. To demonstrate its applicability, the device was used in the quantification of analytes in pharmaceutical drug and synthetic urine samples.

Highly sensitive photoelectrochemical sensors for multichannel detection and uniform bioimaging based on fireworks-like silicon nanowires and its heterojunctions fabricated by MACE and sputtering processes

Photoelectrochemical (PEC) sensors have emerged as a promising candidate for biochemical detection. However, PEC sensors based on bulk semiconductors are limited by sensitivity and detection varieties, though they can provide uniform imaging; PEC sensors based on nanomaterials can meet the requirements of various analytes and sensitivity, but the inhomogeneity of their surface poses a challenge to imaging uniformity. In this work, metal-assisted chemical etching (MACE) and sputtering processes were used to directly fabricated PEC sensors with fireworks-like silicon nanowires (F-SiNWs) and their heterojunctions with excellent performance. Through regulating the etching and sputtering times, the structure and nanomaterials attachment of F-SiNWs can be well controlled. The photoelectric and sensing properties of F-SiNWs with different morphologies were investigated and optimized. Then, the sensor fabricated by optimal F-SiNWs can directly detect H2O2 and indirectly detect glucose under negative bias, while directly detect dopamine (DA) under positive bias. The detection of these three analytes do not interfere with each other, contributing to an excellent multichannel detection system. Subsequently, the multichannel detection of various secretions (H2O2, DA and glucose) of PC-12 cells was achieved by the sensor. Finally, the imaging uniformity of the sensor was demonstrated in different solutions. PEC bioimaging was successfully applied to monitor enzyme activity by bioimaging gradients and cell survival by bioimaging distribution. These results demonstrate the high sensitivity in multichannel detection and excellent stability and homogeneity in bioimaging of the sensor. Therefore, MACE and sputtering process can be a promising tool for constructing PEC sensor.

Nb4C3Tx MXene-AgNPs decorated laser-induced graphene for selective detection of dopamine

In this study, a selective electrochemical sensor based on Nb4C3Tx MXene-silver nanoparticles (Nb4C3Tx MXene-AgNPs) decorated laser-induced graphene (LIG) electrode synthesized from flexible pyralux film was employed to detect dopamine (DA). The characterization of the synthesized LIG, Nb4C3Tx MXene, and AgNPs was conducted using UV–visible spectroscopy, scanning electron microscopy, and Raman spectroscopy. The electrochemical performance of the fabricated LIG electrode was enhanced from a peak anodic current (Ipa) of 150 μA to 330.4 μA upon modification with Nb4C3Tx MXene-AgNPs nanocomposite. The LIG- Nb4C3Tx MXene-AgNPs electrode exhibited high electrocatalytic activity toward the oxidation of DA via cyclic voltammetry and chronoamperometry techniques. The current response increased linearly with DA concentration and exhibited a wide linear range from 100 nM to 10 µM with a detection limit of 1 nM. The sensor also exhibited an excellent sensitivity of 160.96 μA/nM cm−2. Furthermore, the fabricated LIG-Nb4C3Tx MXene-AgNPs electrode showed excellent selectivity toward DA detection in the presence of common interfering compounds such as glucose, ascorbic acid, and uric acid and had high reproducibility. The developed LIG-Nb4C3Tx MXene-AgNPs flexible electrode platform is suitable for accurately and reliably detecting DA in the presence of competing analytes.

Synthesis of a Fluorescent Sensor by Exploiting Nitrogen-Doped MXene Quantum Dots for the Detection of Dopamine

Synthesis of a Fluorescent Sensor by Exploiting Nitrogen-Doped MXene Quantum Dots for the Detection of Dopamine

Synthesis of graphene quantum dots inside a nanoreactor for fluorescence detection of dopamine

A label-free fluorescence sensor for selective detection of dopamine (DA) was developed by using graphene quantum dots (GQDs) as fluorescence probes. The GQDs were prepared via a top-down acid vapor oxidation strategy, in which a hollow carbon @ mesoporous silica nanosphere (h-C@mesoSiO2) serves as nanoreactor and only 1 mL of HNO3 was used as scissors for quickly cleaving the thin carbon layer in the nanospace of h-C@mesoSiO2. The method not only effectively avoids a tedious separation process but also endows GQDs with uniform size and good dispersion. And the as-prepared GQDs display good linear fluorescence response to DA in the range of 0.24–5.86 mM with a low detection limit of 12.7 nM. The proposed sensor shows high selectivity and satisfying recovery for DA detection in human urine. The good specificity toward DA may be due to a) the carboxyl groups on the surface of GQDs can interact with the amine functional groups in DA through electrostatic interactions and b) this specificity is further enhanced by the π–π interaction between GQDs and DA. Importantly, the work not only provides an avenue for the controllable synthesis of GQDs, but also expands the application of GQDs prepared by top-down method to DA sensor.

A novel dual recognition sensor based on molecularly imprinted polymers and photochemical aptamer for non-autofluorescence determination of dopamine

Dopamine (DA), as a neurotransmitter that plays a crucial role in neuronal communication. Abnormal levels of DA concentration in vivo are associated with severe neurological disorders such as Alzheimer’s disease and Parkinson’s disease. Highly selective and highly efficient determination of DA from complex biological samples is very important. In this work, m-MIPs@DA@ZGGC-Apt, a novel sandwich structure persistent luminescence sensor was designed based on a photochemical aptamer sensor and magnetic molecularly imprinted polymers (m-MIPs). By modifying aptamers on the surface of ZGGC persistent luminescent nanoparticles, ZGGC-Apt probes with dual capabilities (recognition and detection) were obtained, which allowed for specific recognition and autofluorescence-free detection of DA. The m-MIPs recognition probe with specific cavity captures of DA was synthesized using Fe3O4 as the imprint carrier. In the presence of both probes, a m-MIPs@DA@ZGGC-Apt sandwich structure was formed continuously in real samples with the increase in DA concentration, resulting in a strong the luminescence response. Under optimal experimental conditions, satisfactory selectivity and sensitivity were obtained by the dual recognition sensor achieved a wide linear range from 0.01 to 100 μM and a low detection limit of 0.0065 μM. Moreover, the designed sensor showed good reliability and practicability in the detection of small molecule DA in real biological samples.