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1.
A nanocomposite (Ho 2O 3NPs/BNT) was synthesized by decorating holmium(III)oxide nanoparticles (H 2O 3NPs) on bentonite (BNT) through a realizable sonochemical approach for the electrochemical detection of haloperidol (Hlp). A glassy carbon electrode was modified with this nanocomposite. The Ho 2O 3NPs/BNT modified electrode outperformed bare and other modified electrodes in terms of electrochemical performance for Hlp detection in a pH 8.0 phosphate buffer. The proposed electrochemical platform showed a wide linear range (0.01 μM–24 μM), low detection limit (2.4 nM), and high sensitivity by square wave voltammetry. In addition, the proposed electrochemical sensor met the clinical criteria in terms of stability, selectivity, and repeatability. 相似文献
2.
In this work, a screen‐printed carbon electrode (SPCE) was modified with a cobalt/porous silicon (Co@PSi) nanocomposite powder to develop a nonenzymatic sensor for the detection of hydrogen peroxide. The Co@PSi nanocomposite was synthesized through the chemical reaction between silicon powder in a HF/HNO 3 solution and cobalt cations. In this process, cobalt nanoparticles were anchored on the porous silicon. The structure and morphology of the synthesized nanocomposite were investigated by X‐ray diffraction, Fourier transform infrared spectroscopy, X‐ray photoemission spectroscopy, energy dispersive X‐ray spectroscopy, and field‐emission scanning electron microscopy. The constructed nonenzymatic, screen‐printed sensors based on the Co@PSi nanocomposite showed perfect electrocatalytic oxidation response to hydrogen peroxide over the range 1–170 and 170–3,770 μmol/L with the limit of detection of 0.8 μmol/L. In addition, the Co@PSi‐SPCE sensor exhibited good selectivity for the determination of H 2O 2 in the presence of common interfering species including glucose, ascorbic acid, uric acid, dopamine, nitrate, and nitrite ions. The constructed electrochemical sensor was successfully used for the determination of H 2O 2 in real samples. 相似文献
3.
The number of studies conducted about nonenzymatic electrochemical sensors has increased in recent years due to the development of more stable and robust electrodes using noble metals. One of the key aspects for achieving high sensing performance including detection limit and sensitivity is the design of electrode architecture. Herein, we report a new electrochemical sensing platform featuring ultrathin standing gold nanowires (AuNWs) for nonenzymatic detection of hydrogen peroxide (H 2O 2). The use of AuNWs resulted in an increased electron transfer efficiency due to the higher active surface area compared to traditional gold film electrodes. This sensor demonstrates good selectivity, reproducibility, a linear range up to 49.5 mM of H 2O 2 with a sensitivity of 0.185±0.003 mAmM ?1cm ?2 and a limit of detection of 111 μM. The biological relevance of this sensor was tested in cell culture media to illustrate the performance of the proposed sensing electrode in complex biological media. 相似文献
4.
A novel strategy to fabricate hydrogen peroxide (H 2O 2) sensor was developed by electrodepositing palladium? silver nanoparticles (NPs) on a glassy carbon electrode. The morphology of the modified electrode was characterized by Scanning electron microscopy (SEM). The result of electrochemical experiments showed that such constructed sensor had a favorable catalytic ability, high sensitivity, excellent selectivity towards reduction of hydrogen peroxide (H 2O 2). The response to H 2O 2 is linear in the range between 0.30 μM to 2.50 mM, and the detection limit is 0.1 μM (at an S/N of 3). 相似文献
5.
Herein, co-electrodeposition of AuNPs and ERGO onto GCE was conducted to prepare the modified electrode, GCE/AuNPs-ERGO. The poly(indole-5-carboxylic acid) (P(In-5-COOH) was then coated onto the GCE/AuNPs-ERGO with the help of electropolymerization. FT-IR, FE-SEM and EDX, and XRD techniques were employed to characterize the prepared nanocomposite. The nanocomposite modified electrode (GCE/AuNPs-ERGO/P(In-5-COOH)) was examined for the electrochemical reduction of H 2O 2 using chronoamperometry. A high reduction current for H 2O 2 was observed due to the synergistic effect between AuNPs-ERGO and P(In-5-COOH). The proposed sensor demonstrated a wide linear range of 0.025–750 μmol L −1, with a LOD of 0.008 μmol L −1 at −0.4 V. Furthermore, the developed sensor was applied for the detection of H 2O 2 in fetal bovine serum and urine samples. 相似文献
6.
At present, a highly sensitive hydrogen peroxide (H 2O 2) sensor is fabricated by ferrocene based naphthaquinone derivatives as 2,3‐Diferrocenyl‐1,4‐naphthoquinone and 2‐bromo‐3‐ferrocenyl‐1,4‐naphthoquinone. These ferrocene based naphthaquinone derivatives are characterized by H‐NMR and C‐NMR. The electrochemical properties of these ferrocene based naphthaquinone are investigated by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS) on modified glassy carbon electrode (GCE). The modified electrode with ferrocene based naphthaquinone derivatives exhibits an improved voltammetric response to the H 2O 2 redox reaction. 2‐bromo‐3‐ferrocenyl‐1,4‐naphthoquinone show excellent non‐enzymatic sensing ability towards H 2O 2 response with a detection limitation of 2.7 μmol/L a wide detection range from 10 μM to 400 μM in H 2O 2 detection. The sensor also exhibits short response time (1 s) and good sensitivity of 71.4 μA mM ?1 cm ?2 and stability. Furthermore, the DPV method exhibited very high sensitivity (18999 μA mM ?1 cm ?2) and low detection limit (0.66 μM) compared to the CA method. Ferrocene based naphthaquinone derivative based sensors have a lower cost and high stability. Thus, this novel non‐enzyme sensor has potential application in H 2O 2 detection. 相似文献
7.
Electrocatalytic activities of graphene nanosheets/Nile blue nanocomposite, synthesized and adsorbed simultaneously on the glassy carbon (GC?GNs?NB) electrode, are investigated. The nanocomposite was characterized by ATR?FTIR, FESEM and voltammetry. Activity of the electrode toward reduction of H 2O 2 and oxidation of NO 2? was studied electrochemically. Values of 1.95 and 0.730 mM are found for the Michaelis?Menten constant of the electrode toward H 2O 2 and NO 2?, respectively. Wide dynamic response ranges were observed for the electrode, with DLs of 0.22 μM H 2O 2 and 1.1 μM NO 2?. Effect of interferences was studied. The sensor was successfully tested for H 2O 2 and NO 2? contents in real samples, respectively. 相似文献
8.
We have developed a 3-dimensional (3-D) electrochemical sensor for highly sensitive detection of hydrogen peroxide (H 2O 2). Porous 3-D carbon nanofibers (CNFs), prepared by electrospinning, served as scaffold on a glassy carbon electrode. The 3-D CNFs were functionalized with platinum nanoparticles (Pt-NPs) by in-situ gas-phase decomposition of platinum salts at high temperature. The Pt-NPs act as an electrocatalyst for the decomposition of H 2O 2. TEM revealed that large amounts of Pt-NPs are deposited in the electrospun CNFs electrode even without using any stabilizer or reducing reagent. The sensor was investigated by cyclic voltammetry and amperometry and displays a good response to H 2O 2 with a linear range between 10 μM and 15 mM ( R?=?0.9994), a low detection limit (3.4 μM at a signal-to-noise ratio of 3), and a response time of 3 s. The sensor shows excellent stability and selectivity. Figure We report the direct growth of the Pt NPs in the 3-D CNFs via electrospinning and sequent thermal treatment. We demonstrate the use of 3-D architecture novel Pt/CNFs electrode for nonenzymatic electrochemical sensing of H 2O 2. The sensor shows outstanding performance in terms of detection range, detection limit, response time, stability and selectivity. 相似文献
9.
Magnetic carbon-coated iron nanoparticles were used to immobilize horseradish peroxidase on the surface of a polythionine modified glassy carbon electrode in combination with chitosan and cross-linking of glutaraldehyde. The electrochemical character of this enzyme electrode and its electrocatalytic reduction to H2O2 were studied by cyclic voltammetry. The effects of the common experimental variables were investigated. Under the optimum conditions, this method could be successfully used for the amperometric determination of H2O2 in a wide concentration range of 9.6 μM to 3.16 mM with a detection limit of 3.6 μM (S/N=3). Besides, the biosensor also exhibited good selectivity, stability and reproducibility. 相似文献
10.
A novel nonenzymatic H 2O 2 sensor based on a palladium nanoparticles/graphene (Pd‐NPs/GN) hybrid nanostructures composite film modified glassy carbon electrode (GCE) was reported. The composites of graphene (GN) decorated with Pd nanoparticles have been prepared by simultaneously reducing graphite oxide (GO) and K 2PdCl 4 in one pot. The Pd‐NPs were intended to enlarge the interplanar spacing of graphene nanosheets and were well dispersed on the surface or completely embedded into few‐layer GN, which maintain their high surface area and prevent GN from aggregating. XPS analysis indicated that the surface Pd atoms are negatively charged, favoring the reduction process of H 2O 2. Moreover, the Pd‐NPs/GN/GCE could remarkably decrease the overpotential and enhance the electron‐transfer rate due to the good contact between Pd‐NPs and GN sheets, and Pd‐NPs have high catalytical effect for H 2O 2 reduction. Amperometric measurements allow observation of the electrochemical reduction of H 2O 2 at 0.5 V (vs. Ag/AgCl). The H 2O 2 reduction current is linear to its concentration in the range from 1×10 ?9 to 2×10 ?3 M, and the detection limit was found to be 2×10 ?10 M ( S/ N=3). The as‐prepared nonenzymatic H 2O 2 sensor exhibits excellent repeatability, selectivity and long‐term stability. 相似文献
11.
A glassy carbon electrode (GCE) was modified with nickel(II) hydroxide nanoparticles and a film of molybdenum sulfide. The nanocomposite was prepared by two-step electrodeposition. Scanning electron microscopy reveals that the nanoparticles are uniformly deposited on the film. Cyclic voltammetry and chronoamperometry indicate that this modified GCE displays a remarkable electrocatalytic activity towards nonenzymatic oxidation of glucose. Response is linear in the 10–1,300 μM concentration range ( R 2 ?=?0.9987), the detection limit is very low (5.8 μM), response is rapid (< 2 s), and selectivity over ascorbic acid, dopamine, uric acid, fructose and galactose is very good. Figure An efficient nonenzymatic glucose sensor based on Ni(OH) 2/MoS x nanocomposite modified glassy carbon electrode has been fabricated via a two-step electrodeposition approach. The resulting nonenzymatic sensor exhibits excellent properties toward glucose detection, such as low detection limit, fast response and noticeable selectivity. 相似文献
12.
The present study describes a novel and very sensitive electrochemical assay for determination of hydrogen peroxide (H 2O 2) based on synergistic effects of reduced graphene oxide‐ magnetic iron oxide nanocomposite (rGO‐Fe 3O 4) and celestine blue (CB) for electrochemical reduction of H 2O 2. rGO‐Fe 3O 4 nanocomposite was synthesized and characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X‐ray diffraction (XRD), electrochemical impedance spectroscopy and cyclic voltammetry. Chitosan (Chit) was used for immobilization of amino‐terminated single‐stranded DNA (ss‐DNA) molecules via a glutaraldehyde (GA) to the surface of rGO‐Fe 3O 4. The MTT (3‐(4,5‐Dim ethylt hiazol‐2‐yl)‐2,5‐diphenylt etrazolium bromide) results confirmed the biocompatibility of nanocomposite. Experimental parameters affecting the ss‐DNA molecules immobilization were optimized. Finally, by accumulation of the CB on the surface of the rGO‐Fe 3O 4‐Chit/ssDNA, very sensitive amperometric H 2O 2 sensor was fabricated. The electrocatalytic activity of the rGO‐Fe 3O 4‐Chit/DNA‐CB electrode toward H 2O 2 reduction was found to be very efficient, yielding very low detection limit (DL) of 42 nM and a sensitivity of 8.51 μA/μM. Result shows that complex matrices of the human serum samples did not interfere with the fabricated sensor. The developed sensor provided significant advantages in terms of low detection limit, high stability and good reproducibility for detection of H 2O 2 in comparison with recently reported electrochemical H 2O 2 sensors. 相似文献
13.
The synthesis of NiO/NiCo 2O 4 nanoparticles by an eco-friendly, fast, simple and cost-effective approach employing Urtica extract is reported in this study. The NiO/NiCo 2O 4 nanocomposite were characterized using VSM, FTIR, XRD, and SEM techniques. Moreover, to construct a modified carbon paste electrode, NiO/NiCo 2O 4 were employed and this sensor was used for dopamine (DA) detection. Using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques, the electrochemical behavior of dopamine at the NiO/NiCo 2O 4/CPE was investigated. Analysis of dopamine, with a limit of detection (LOD) equal to 0.04 μM, in the concentration range of 0.1–100.0 μM, was facilitated by NiO/NiCo 2O 4/CPE. Moreover, the satisfactory selectivity for DA determination in the presence of uric acid (UA) and ascorbic acid (AA), was obtained. The suggested new sensor displayed a good reproducibility, sensitivity, and stability for determination of DA in drug and biological samples. 相似文献
14.
To achieve highly sensitive nonenzymatic detection of H 2O 2, a novel electrochemical sensor based on Fe 3O 4-Ag nanocomposites was developed. Nanocomposites were synthesized by reducing [Ag(NH 3) 2] + at the gas/liquid interface in the presence of silver seeds and confirmed by transmission electron microscopy and X-ray diffractometry. Electrochemical investigations indicate that the sensor is able to detect H 2O 2 within a wide linear range of 0.5 μM to 4.0 mM, sensitivity of 135.4 μA mM ?1 cm ?2 and low detection limit of 0.2 μM ( S/N = 3). Additionally, the sensor exhibits good anti-interference ability, stability and repeatability. These results show that the Fe 3O 4-Ag nanocomposite is a promising electrocatalytic material for sensors construction. 相似文献
15.
In the present study, a novel enzymatic glucose biosensor using glucose oxidase (GOx) immobilized into (3‐aminopropyl) triethoxysilane (APTES) functionalized reduced graphene oxide (rGO‐APTES) and hydrogen peroxide sensor based on rGO‐APTES modified glassy carbon (GC) electrode were fabricated. Nafion (Nf) was used as a protective membrane. For the characterization of the composites, Fourier transform infrared spectroscopy (FTIR), X‐ray powder diffractometer (XRD), and transmission electron microscopy (TEM) were used. The electrochemical properties of the modified electrodes were investigated using electrochemical impedance spectroscopy, cyclic voltammetry, and amperometry. The resulting Nf/rGO‐APTES/GOx/GC and Nf/rGO‐APTES/GC composites showed good electrocatalytical activity toward glucose and H 2O 2, respectively. The Nf/rGO‐APTES/GC electrode exhibited a linear range of H 2O 2 concentration from 0.05 to 15.25 mM with a detection limit (LOD) of 0.017 mM and sensitivity of 124.87 μA mM −1 cm −2. The Nf/rGO‐APTES/GOx/GC electrode showed a linear range of glucose from 0.02 to 4.340 mM with a LOD of 9 μM and sensitivity of 75.26 μA mM −1 cm −2. Also, the sensor and biosensor had notable selectivity, repeatability, reproducibility, and storage stability. 相似文献
16.
A novel non‐enzymatic glucose sensor based on nickel hydroxide and intercalated graphene with ionic liquid (G‐IL) nanocomposite modified glass carbon electrode was fabricated. Scanning electron microscope, Fourier transform infrared spectra and energy dispersive X‐ray spectroscopy of the nanocomposite confirmed the morphology and ingredient of Ni(OH) 2 as well as G‐IL. Moreover, experimental results of cyclic voltammetry, electrochemical impedance spectroscopy and chronoamperometry indicated the sensing properties of Ni(OH) 2 at Ni(OH) 2/G‐IL modified electrode towards the typical electrocatalytic oxidation process of glucose at 0.43 V in 0.10 M NaOH. The current response was linearly related to glucose concentration in a range from 0.5 to 500 μM with a detection limit of 0.2 μM (S/N = 3) and sensitivity of 647.8 μA mM ?1 cm ?2. The response time of the sensor to glucose was less than 2 s. This work may be expected to develop an excellent electrochemical sensing platform of G‐IL as a catalysis carrier. 相似文献
17.
A sensitive hydrogen peroxide (H 2O 2) sensor was fabricated based on graphene–Pt (GN–Pt) nanocomposite. The GN–Pt was synthesized by photochemical reduction of K 2PtCl 4 on GNs, and characterized by atomic force microscope (AFM), transmission electron microscope (TEM), and energy-dispersive X-ray spectroscopy (EDS). Electrochemical investigations indicated that the GN–Pt exhibited a high peak current and low overpotential towards the reduction of H 2O 2. The GN–Pt modified glass carbon electrode displayed a wide linear range (2–710 μM), low limit of detection (0.5 μM) and good selectivity for detection of H 2O 2 with a much higher sensitivity than that of Pt nanoparticles or graphene modified electrode. 相似文献
18.
A newly nonenzymatic sensor for hydrogen peroxide (H 2O 2) based on the (Au‐HS/SO 3H‐PMO (Et)) nanocomposite is demonstrated. The electrochemical properties of the as‐prepared nanocomposite were studied. It displayed an excellent performance towards H 2O 2 sensing in the linear response range from 0.20 µM to 4.30 mM ( R=0.9999) with a sensitivity of 6.35×10 2 µA µM ?1 cm ?2 and a low detection limit of 0.0499 µM. Furthermore, it was not affected by electroactive interference species. These features proved that the modified electrode was suitable for determination of H 2O 2. 相似文献
19.
A high-sensitive nonenzymatic hydrogen peroxide (H 2O 2) biosensor based on cuprous iodide and graphene (CuI/Gr) composites has been explored for the detection of H 2O 2 released by living cells and monitoring the oxidative stress of cells under excellular stimulation. The biosensor properties were evaluated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), amperometric i-t curve, and the redox-competition mode of scanning electrochemical microscopy (SECM). Our observations demonstrate that the CuI/Gr nanocomposites modified glassy carbon electrode (GCE) exhibits excellent catalytic activity for H 2O 2 with relatively low detection limit and a wide linear range from 0.5 μM to 3 mM. Moreover, the redox-competition mode of SECM imaging study further illustrates the improved electrochemical catalytic capability for H 2O 2 reduction with CuI/Gr nanocomposites deposited on graphite electrode. Hence, the as-prepared nonenzymatic H 2O 2 biosensor could be used to detect H 2O 2 release from different kinds of living cells under stimulation while eliminating the interference of ascorbic acid. 相似文献
20.
Developing non‐noble‐metal electrocatalyst for non‐enzymatic H 2O 2 sensing is highly attractive. A facile, two‐step approach has been utilized for the synthesis of PBNCs/SnO 2 QDs/RGO ternary nanocomposite. TEM, SEM, XPS, and XRD techniques were used to the characterize the structural and morphological properties of synthesized ternary nanocomposite. The synthesized ternary nanocomposite has been examined as an electrode material for the electrochemical detection of H 2O 2 using the Amperometry technique. Under optimum conditions, PBNCs/SnO 2 QDs/RGO ternary nanocomposite performed very well in the electrocatalytic reduction of H 2O 2 with a linear dynamic range from 25–225 μM (R 2=0.996) with a low detection limit of 71 nM (S/N=3). Compared to the recent literature, PBNCs/SnO 2QDs/RGO ternary nanocomposite based modified electrode exhibit a wider linear dynamic range with a low detection limit. Furthermore, PBNCs/SnO 2 QDs/RGO ternary nanocomposite based modified electrode showed an excellent anti‐interference ability against various common interfering agents. The practical applicability of this ternary nanocomposite based modified electrode was further extended to determine the H 2O 2 in tap water with acceptable recovery. The present performance of PBNCs/SnO 2 QDs/RGO ternary nanocomposite material towards H 2O 2 sensing might widen its application for developing a new type of non‐noble metal‐based non‐enzymatic electrochemical biosensors. 相似文献
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