Simultaneous Detection Of Uric Acid Research Articles

A wearable flexible electrochemical biosensor with CuNi-MOF@rGO modification for simultaneous detection of uric acid and dopamine in sweat

BackgroundIn health assessment and personalized medical services, accurate detection of biological markers such as dopamine (DA) and uric acid (UA) in sweat is crucial for providing valuable physiological information. However, there are challenges in detecting sweat biomarkers due to their low concentrations, variations in sweat yield among individuals, and the need for efficient sweat collection. ResultsWe synthesized CuNi-MOF@rGO as a high-activity electrocatalyst and investigated its feasibility and electrochemical mechanism for simultaneously detecting low-concentration biomarkers UA and DA. Interaction between the non-coordinating carboxylate group and the sample produces effective separation signals for DA and UA. The wearable biomimetic biosensor has a wide linear range of 1–500 μM, with a detection limit of 9.41 μM and sensitivity of 0.019 μA μM−1 cm−2 for DA, and 10–1000 μM, with a detection limit of 9.09 μM and sensitivity of 0.026 μA μM−1 cm−2 for UA. Thus, our sensor performs excellently in detecting low-concentration biomarkers. To improve sweat collection, we designed a microfluidic-controlled device with hydrophilic modification in the microchannel. Experimental results show optimal ink flow at 2% concentration. Overall, we developed an innovative and highly active electrocatalyst, successfully enabling simultaneous detection of low-concentration biomarkers UA and DA. SignificanceThis study provides a strategy for sweat analysis and health monitoring. Moreover, the sensor also showed good performance in detecting real sweat samples. This study has shown great potential in future advances in sweat analysis and health monitoring.

Development of a facile electrochemical sensor based on GCE modified with one-step prepared PNMA-CeO2-fMWCNTs composite for simultaneous detection of UA and 5-FU.

In this study, a poly(N-methyl aniline)-cerium oxide-functionalized MWCNTs (PNMA-CeO2-fMWCNTs) composite was synthesized in a one-step preparation technique. As a highly efficient modifier, the composite was used to modify the glassy carbon electrode surface for simultaneous detection of uric acid (UA) and 5-fluorouracil (5-FU). Morphological characterization of the GCE/PNMA-CeO2-fMWCNTs was studied using scanning electron microscopy. Structural characterization of the composite was performed using X-ray diffraction and Fourier-transformed infrared spectroscopy. Electron transfer properties of the prepared electrodes were carried out with electrochemical impedance spectroscopy and cyclic voltammetry. The linear working range for UA and 5-FU was found to be 0.25-50 μM and 0.5-750 μM, respectively. The limit of detection values for UA and 5-FU were 0.04 μM and 0.19 μM, respectively. The effects of various interfering substances on the electrochemical response of UA and 5-FU were investigated. The GCE/PNMA-CeO2-fMWCNTs sensor has excellent stability, reproducibility, anti-interference ability, and reproducibility. To demonstrate the practical application of the sensing platform, fetal bovine serum was selected and tested in the spiked samples, and satisfactory results were obtained. The prepared composite proved to be a promising platform for simple, rapid, and simultaneous analysis of UA and 5-FU.

Multifunctional electrode materials based on brochantite for the fabrication of high-stability supercapacitors and dual-mode uric acid/17β-estradiol electrochemical sensors

Compared to other transition metal-based materials, copper-based materials are often neglected despite their several advantages, such as facile redox properties, high stability, and low cost. For the first time, novel electrode materials based on brochantite were tested as supercapacitors and uric acid/17β-estradiol sensors. Brochantite (Cu4SO4(OH)6) was synthesized using the one-step solvothermal method. Upon thermal annealing, it was converted to dolerophanite (Cu2O(SO4)) and copper (II) oxide (CuO). The composite electrodes, combining brochantite, dolerophanite, copper (II) oxide, and polyaniline, were prepared. Interestingly, the quaternary composite synergistically gave a specific capacitance as high as 376 F g−1 and a capacitance retention of 95.34 % after 10,000 cycles, which are much better than each of its parent compounds. The analysis of variance was performed to elucidate the relationship between the materials and specific capacitance. Furthermore, the novel brochantite/polyaniline composite electrode demonstrated superb electrochemical sensing activity for the simultaneous detection of uric acid and 17β-estradiol. Based on these findings, the composite electrodes based on brochantite can multi-function as high-performance supercapacitor components and for the dual-mode, simultaneous detection of uric acid and 17β-estradiol. This work will also open the door for the search for new copper-based materials for a variety of electrochemical applications.

Single-Atom Indium Boosts Electrochemical Dopamine Sensing.

A rational design of high-efficiency electrocatalysts and thus achieving sensitive electrochemical sensing remains a great challenge. In this work, single-atom indium anchored on nitrogen-doped carbon (In1-N-C) with an In-N4 configuration is prepared successfully through a high-temperature annealing strategy; the product can serve as an advanced electrocatalyst for sensitive electrochemical sensing of dopamine (DA). Compared with In nanoparticle catalysts, In1-N-C exhibits high catalytic performance for DA oxidation. The theoretical calculation reveals that In1-N-C has high adsorption energy for hydroxy groups and a low energy barrier in the process of DA oxidation compared to In nanoparticles, indicating that In1-N-C with atomically dispersed In-N4 sites possesses enhanced intrinsic activity. An electrochemical sensor for DA detection is established as a concept application with high sensitivity and selectivity. Furthermore, we also verify the feasibility of In1-N-C catalysts for the simultaneous detection of uric acid, ascorbic acid, and DA. This work extends the application prospect of p-block metal single-atom catalysts in electrochemical sensing.

A Dual-Function Wearable Electrochemical Sensor for Uric Acid and Glucose Sensing in Sweat.

Simultaneous detection of uric acid and glucose using a non-invasive approach can be a promising strategy for related diseases, e.g., diabetes, gout, kidney disease, and cardiovascular disease. In this study, we have proposed a dual-function wearable electrochemical sensor for uric acid and glucose detection in sweat. The sensor with a four-electrode system was prepared by printing the ink on a common rubber glove. CV and chronoamperometry were used to characterize the prepared sensor's electrochemical sensing performance. The sensors exhibited the linear range from 0 to 1.6 mM and 0 to 3.7 mM towards uric acid and glucose electrochemical sensing in phosphate-buffered solution, with the corresponding limit of detection of 3.58 μM and 9.10 μM obtained, respectively. Moreover, the sensors had shown their feasibility of real sample sensing in sweat. The linear detection range for uric acid (0 to 40 μM) and glucose (0 to 1.6 mM) in the sweat can well cover their concentration range in physiological conditions. The prepared dual-function wearable electrochemical sensor features easy preparation, fast detection, high sensitivity, high selectivity, and the practical application potential in uric acid and glucose sensing.

Screen printing and laser-induced flexible sensors for the simultaneous sensitive detection of uric acid, tyrosine, and ascorbic acid in sweat.

A wearable sweat sensor, which could continuously monitor biomolecules related to the human physiological state, is emerging as a promising piece of health surveillance equipment. However, current sensors cannot simultaneously achieve a detection performance that equates to that of traditional sensors and satisfactory mechanical strength. Herein, a wearable sweat sensor with excellent detection performance and mechanical stability is designed and fabricated. Based on the integration of laser-induced graphene electrodes and a screen printing technique, this wearable sweat sensor could realize both the separate and simultaneous detection of uric acid (UA), tyrosine (Tyr), and ascorbic acid (AA) with high sensitivity. Good UA sensing performance in artificial sweat could be maintained even after 20 000 bends. In addition, the sensor can operate well in the wearing state or in a complex bovine whole blood sample. For the detection of human sweat, the changes in UA concentration after a purine-rich meal are continuously monitored and the results are in accordance with the corresponding serum UA detection results tested with a commercial serum UA meter. These results suggest its application potential in health monitoring for both gout patients and healthy humans.

A voltammetric sensor based on a reduced graphene oxide/β-cyclodextrin/silver nanoparticle/polyoxometalate nanocomposite for detecting uric acid and tyrosine.

In the present work, an electrochemical sensor based on reduced graphene oxide/β-cyclodextrin/silver nanoparticle/polyoxometalate (RGO-CD-AgNP-POM) was developed for the simultaneous detection of uric acid (UA) and L-tyrosine (L-Tyr). First, an RGO-CD-AgNP-POM nanocomposite was synthesized via a simple photoreduction method and characterized by transmission electron microscopy (TEM), energy dispersive X-ray imaging (EDS), scanning electron microscopy (SEM), and thermal gravimetric analysis (TGA). As an electrode material, RGO-CD-AgNP-POM showed wide linear ranges (0.5-500 μM for UA, and 1-400 μM for L-Tyr) and relatively low detection limits (0.11 μM for UA, and 0.23 μM for L-Tyr). In addition, the combination of supramolecular recognition from CD and excellent electrochemical performances from RGO, AgNPs and POM was expected to enhance the sensing performances toward UA and L-Tyr in real samples with favorable recovery ranges (99%-104%). This nanocomposite provides a new platform for developing the family of electrode materials.

A novel triazine-based covalent organic framework combined with AuNPs and reduced graphene oxide as an electrochemical sensing platform for the simultaneous detection of uric acid, dopamine and ascorbic acid

In this work, a novel triazine-based covalent organic framework (TS-COF) was constructed by the condensation of 1, 3, 5-tris-(4-aminophenyl)triazine (TAPT) and squaric acid (SA) under solvothermal condition. By in situ growth of Au nanoparticles (AuNPs) on the surface of TS-COF, the AuNPs@TS-COF composite with enhanced electroactivity was prepared successfully. After introduction of reduced graphene oxide (RGO), the constructed AuNPs@TS-COF/RGO nanocomposite modified electrode exhibited excellent conductivity and outstanding catalytic activity, and could be employed to determine uric acid (UA), dopamine (DA) and ascorbic acid (AA) in urine sample simultaneously, accurately and rapidly with high sensitivity, good selectivity and high stability. The detection limits of UA, DA and AA were 0.07 μM, 0.03 μM and 4.30 μM (S/N = 3), respectively.

Electrochemical detection of uric acid and ascorbic acid using r-GO/NPs based sensors

A sensitive and selective electrochemical sensor, based on reduced graphene oxide and gold nanoparticles obtained by simple co-electrodeposition, was developed for the detection of uric acid and ascorbic acid. Because of the electrochemical oxidation of both uric and ascorbic acid depending on the pH, the sensor performances were studied at different pH values. Excellent results were obtained for uric acid detection in a linear range from 10 to 500 µmol dm−3 with a sensitivity of 0.31 µA cm−2 µM−1. A limit of detection and quantification of 3.6 µM and 10.95 µmol dm−3, respectively, was calculated. Sensors showed good selectivity toward different interfering species present in the matrix of milk, fruit juice and urine (Na+, NH4+, Cl− and glucose). A simultaneous detection of uric acid and ascorbic acid was also carried out reaching a limit of detection of 2.26 and 5.63 µmol dm−3, respectively. Sensors were also validated measuring both acids in real samples of foods and body fluids (commercial milk and fruit juice and urine). Excellent results were achieved in good agreement with conventional techniques.

Flexible and disposable gold nanoparticles-N-doped carbon-modified electrochemical sensor for simultaneous detection of dopamine and uric acid

Catalytic and electrocatalytic applications of supported metal nanoparticles are hindered due to an aggregation of metal nanoparticles and catalytic leaching under harsh operations. Hence, stable and leaching free catalysts with high surface area are extremely desirable but also challenging. Here we report a gold nanoparticles-hosted mesoporous nitrogen doped carbon matrix, which is prepared using bovine serum albumin (BSA) through calcination. BSA plays three roles in this process as a reducing agent, capping agent and carbon precursor, hence the protocol exhibits economic and sustainable. Gold nanoparticles at N-doped BSA carbon (AuNPs@NBSAC)-modified three-electrode strip-based flexible sensor system has been developed, which displayed effective, sensitive and selective for simultaneous detection of uric acid (UA) and dopamine (DA). The AuNPs@NBSAC-modified sensor showed an excellent response toward DA with a linear response throughout the concentration range from 1 to 50 μM and a detection limit of 0.05 μM. It also exhibited an excellent response toward UA, with a wide detection range from 5 to 200 μM as well as a detection limit of 0.1 μM. The findings suggest that the AuNPs@NBSAC nanohybrid reveals promising applications and can be considered as potential electrode materials for development of electrochemical biosensors.

One Pot Hydrothermal Synthesis of Large Area Nano Cube Like ZnSnO3 Perovskite for Simultaneous Sensing of Uric Acid and Dopamine Using Differential Pulse Voltammetry

We report ultra-selective zinc stannate nano cubes (ZnSnO3) modified glassy carbon electrode (GCE) for simultaneous detection of Uric Acid (UA) and Dopamine (DA) using differential pulse voltammetry (DPV) technique. The ZnSnO3 nano cubes were synthesized via one-pot hydrothermal technique. The orthorhombic phase formation of nano cubes structured ZnSnO3 was confirmed through X-ray diffraction (XRD) and scanning electron microscopy (SEM) imaging. The sensor exhibited very distinct oxidation potentials and excellent sensitivity with wide dynamic ranges of detection ranging from 10 nM to $5~\mu \text{M}$ and $1~\mu \text{M}$ to 5 mM with a very low limit of detections of 2.6 nM and 550 nM towards DA and UA respectively. The sensing mechanism can be ascribed to the simultaneous electro-oxidation process of DA and UA at the 3d orbital SnO6 octahedra sites facilitated with the Sn2+/Sn4+ oxidation states of Sn in line with the stress induced electrical property transformation of ZnSnO3 due to its piezoelectric nature. The as fabricated ZnSnO3/GCE sensor was further successfully evaluated for simultaneous detection of UA and DA in the simulated blood serum samples. This simple strategy for developing ZnSnO3 perovskite modified electrode paves way to develop electrochemical sensing platforms for bioanalytical applications.

CuO Hollow Cubic Caves Wrapped with Biogenic N-Rich Graphitic C for Simultaneous Monitoring of Uric Acid and Xanthine.

Herein, we synthesized hollow cubic caves of CuO (HC) and wrapped it with N-rich graphitic C (NC), derived from a novel biogenic mixture composed of dopamine (DA) and purine. The synthesized NC wrapped HC (NC@HC) sensor shows enhanced electrocatalytic efficacy compared to unwrapped CuO with shapes including HC, sponge (SP), cabbage (CB), and solid icy cubes (SC). The shape and composition of synthesized materials were confirmed through field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS), whereas interfacial surface energy was calculated through contact angle measurement. The designed NC@HC sensor shows a remarkable response toward the simultaneous detection of uric acid (UA) and xanthine (Xn) with detection limits of 0.017 ± 0.001 (S/N of 3) and 0.004 ± 0.001 μM (S/N of 3), respectively. In addition, this platform was successfully applied to monitor UA from the gout patient serum. To the best of our knowledge, this is the first report on using such novel NC@HC materials for the simultaneous monitoring of UA and Xn.

High Electrochemical Activity Induced by Doping Oxygen in Graphene Sheets Embedded Carbon Film

AbstractIn this work, the high electrochemical activity induced by doping different contents of oxygen on the surface of graphene sheets embedded carbon (GSEC) film is studied, which is prepared by electron cyclotron resonance (ECR) plasma sputtering system under electron irradiation. Transmission electron microscopy observation and Raman analysis confirm that doping oxygen induced more graphene edges and oxygen‐containing functional groups on the surface. The electrochemical activities of the films are measured in the redox system and the results show that a proper doping content of oxygen is beneficial to reduce the oxidation‐reduction peak separation. The surface O‐doped GSEC film with 5% content realizes the simultaneous detection of uric acid (UA), xanthine (XA) and hypoxanthine (HXA) with high sensitivity. The mechanism could be that the isolated electron at graphene edge and the polar fraction of oxygen‐containing functional groups provide more active sites to accelerate the electron transfer. These results indicate that surface O‐doped GSEC films are promising electrode materials to construct sensitive electrochemical biosensors.

G‐C3N4/Co Nanohybrids for Ultra‐sensitive Simultaneous Detection of Uric Acid and Dopamine

AbstractA highly sensitive and selective electrochemical sensor based on g‐C3N4/Co nanohybrids was developed for simultaneous detection of uric acid and dopamine. The g‐C3N4/Co nanohybrid modified electrode shows excellent catalytic response towards the oxidation of uric acid and dopamine, with an anodic peak during differential pulse voltammetry at around 300 mV and 150 mV (Ag/AgCl) taken at pH 7.4, respectively. Good linear relationships between peak current intensities and concentrations were obtained in the range of 1 to 1000 μM and 1 to 400 μM for uric acid and dopamine, and the limit of detection (S/N=3) was 0.4 μM and 0.5 μM, respectively. Further analysis revealed the key role of synergistic effect of Co NPs and g‐C3N4 in boosting the oxidation of uric acid and dopamine. The newly developed sensor was successfully applied to human serum samples for a fast‐electrochemical determination of uric acid. These results demonstrate that the g‐C3N4/Co nanohybrid is a promising candidate of advanced electrode material in electrochemical sensing and other electrocatalytic applications.

Zinc Oxide-Carbon Cloth Nanosensors for Simultaneous Detection of Uric Acid, Epinephrine, and Ascorbic Acid

We present a flexible, inexpensive electrochemical sensor using zinc oxide (ZnO) grown directly on carbon cloth for the simultaneous detection of uric acid (UA), epinephrine (EP), and ascorbic acid (AA). The simultaneous detection of these biomolecules poses inherent challenges since their concentrations in the human body are low and the obtained signals are difficult to deconvolve. These limitations were overcome by using nanostructured ZnO on three dimensionally woven carbon fibers as a high surface area biosensing platform. Additionally, a differential pulse voltammetry (DPV) detection technique was used to overcome the bottleneck of clearly resolving signals from UA, EP and AA. The results obtained demonstrate the simultaneous detection of UA, EP and AA. The lowest simultaneously detected concentrations were 2.5 μM for UA, 4.0 μM for EP, and15 μM for AA, in the presence of the remaining two molecules at concentrations of 50 μM for UA and EP and 600 μM for AA. We have also successfully scaled down the biosensing platform to a single carbon fiber with ZnO to demonstrate similar results. Our results indicate that the prepared biosensor was robust, highly sensitive, and stable. Figure 1

Multiwalled carbon nanotube-based nanosensor for ultrasensitive detection of uric acid, dopamine, and ascorbic acid

A novel multiwalled carbon nanotube (MWCNT) based sensor was fabricated as a highly precise and stable electrochemical sensor. The synthesized sensor which consists of ZnNi bimetallic nanoalloy called the ZnNi NPs@f-MWCNT sensor, have been used for the simultaneous detection of uric acid (UA), dopamine (DA) and ascorbic acid (AA). The ZnNi NPs@f-MWCNT sensor obtained based on the microwave irradiation process, and its characterization was performed by using several physical techniques such as XRD, XPS, TEM, Raman, etc. The characterization showed that this sensor has excellent properties such as rich pore channels, excellent structural durability, and large surface area. These properties facilitated mass transfer and electron conductions. It was observed that the obtained sensor gave high electrochemical activity and wide linear responses (0.3–1.1 mM AA, 0.2–1.2 mM DA, 0.2–1.1 mM UA) in the detection of uric acid (UA), dopamine (DA) and ascorbic acid (AA). In addition to these properties, it has been found that the sensor has excellent anti-interferents properties towards AlCl3, KCl3, glucose, etc. and ZnNi NPs@f-MWCNT sensor was further applied to determine uric acid (UA), dopamine (DA) and ascorbic acid (AA) in real samples.

Investigating the electrochemical behaviour and detection of uric acid on ITO electrodes modified with differently doped N-graphene films

Sensitive and selective electrochemical sensors based on indium-doped tin oxide electrodes (ITO) modified with differently nitrogen-doped graphene (NGr) films were successfully developed for the individual and simultaneous determination of uric acid (UA) in the presence of ascorbic acid (AA). The influence of the contents of various N-configurations on the detection of UA on the NGr/ITO based sensors is herein reported for the first time. The contents of various N-configurations on the NGr/ITO electrodes displayed varying promotional effects of the electro-oxidation of UA; attributed to the unique properties of the NGr films arising from the N-configurations. In particular, three N-doped materials prepared with varying amount of graphitic-N, pyrrolic-N, and pyridinic-N allowed the individual detection of UA, in the presence of AA, in the concentration range from 2 to 320μM with the detection limits of 0.043μM to 0.19μM. Finally, the NGr/ITO-based sensors exhibited successful simultaneous detection of UA and AA, depicting detection limits of 0.051–0.19μM and 0.93–5.1μM within the concentration ranges of 6–280μM and 8–800μM, for the detection of UA and AA, respectively. The study provided insight into an understanding as to how the different contents of N-configurations influenced the electrocatalytic activity of NGr/ITO electrodes for the individual and simultaneous detection of uric acid.

Electrodeposition of poly(3,4-ethylenedioxythiophene)/reduced graphene oxide/manganese dioxide for simultaneous detection of uric acid, dopamine and ascorbic acid

A simple and sensitive sensor of poly(3,4-ethylenedioxythiophene)/reduced graphene oxide/manganese dioxide modified glassy carbon electrode (PrGO/MnO2) was fabricated via cyclic voltammetry (CV) for simultaneous detection of uric acid (UA), dopamine (DA) and ascorbic acid (AA). The PrGO/MnO2 composite film possessed excellent electrocatalytic rate and high selectivity towards the oxidation of UA, DA and AA in 0.1 M PBS (pH 6.0). The peak potential separation (∆Ep) of AA-DA, AA-UA and DA-UA were 166, 312 and 146 mV, respectively. The detection limits of 1.00, 0.02 and 0.05 μM with a linear response of 1–800, 0.03–45 and 0.3–80 μM were obtained for AA, DA and UA, respectively. This sensor also showed an excellent stability (reproducibility and repeatability).

Simultaneous determination of uric acid, xanthine and hypoxanthine based on sulfonic groups functionalized nitrogen-doped graphene

Abstract A highly sensitive and selective method was developed for simultaneous detection of uric acid (UA), xanthine (XA) and hypoxanthine (HX) based on a 1,3,6,8-pyrene tetra sulfonic acid sodium salt functionalized nitrogen-doped graphene (PyTS–NG) composite. The material was synthesized by utilizing a facile ultrasonic method via π–π conjugate action between 1,3,6,8-pyrene tetra sulfonic acid sodium salt (PyTS) and nitrogen-doped graphene (NG) molecule. Compared with pristine NG, the material had better dispersivity and conductivity, which might be attributed to a large number of edge-plane-like defective sites on the surface of PyTS–NG that would accelerate electron transfer between electrode and species in solution. The surface morphology was characterized by scanning electron microscopy and transmission electron microscopy. The electrochemical behaviors of UA, XA and HX on the surface of PyTS–NG were investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Under the optimized condition, the linear ranges for the determination of UA, XA and HX were 9–1000, 8–800 and 8–200 μM, with the detection limits (S/N = 3) of 0.331, 0.0838 and 0.231 μM, respectively. Furthermore, the practical application of the present method was evidenced by determining UA, XA and HX in human blood serum and urine samples.

A highly sensitive electrochemical sensor for simultaneous detection of uric acid, xanthine and hypoxanthine based on poly(l-methionine) modified glassy carbon electrode

A poly l-methionine modified GC electrode was fabricated by electrochemical polymerization of the l-methionine on a glassy carbon electrode. The electrochemical behaviors of uric acid, xanthine and hypoxanthine at the modified electrode were studied by cyclic voltammetry and differential pulse voltammetry. The results showed that this modified electrode exhibited excellent electrocatalytic activity toward the oxidation of the uric acid, xanthine and hypoxanthine. Also, electrode was used for simultaneous determination of uric acid, xanthine and hypoxanthine. This modified electrode possesses high sensitivity, and the detection limits as values 0.007, 0.004 and 0.008μM for uric acid, xanthine and hypoxanthine, respectively. Finally, the poly l-methionine modified electrode was successfully employed to detect uric acid, xanthine and hypoxanthine in the serum samples with good selectivity and high sensitivity.