Electrochemical Behavior Of Epinephrine Research Articles

A novel copper ion enhanced electrochemical DNA biosensor for the determination of epinephrine

A novel electrochemical biosensor was developed for the detection of epinephrine (EP) by immobilizing double-strand DNA (dsDNA) bound with copper ions on a gold electrode (Cu2+/dsDNA/MCH/AuE). The electrochemical behavior of EP at Cu2+/dsDNA/MCH/AuE was examined, and the results demonstrated a significant enhancement in the electrocatalytic oxidation peak current of EP due to the formation of a stable G-Cu(II)-G sandwich structure between Cu2+ and guanine at the modified electrode. The modification process of the electrode was characterized by scanning electron microscopy, infrared spectroscopy, electrochemical impedance spectroscopy, and differential pulse voltammetry. A study on the effect of pH in phosphate buffer solution on the electrochemical oxidation of EP indicated that the catalytic oxidation process was pH-dependent. A plot of catalytic current versus EP concentration exhibited a dual-linear relationship within two ranges: 1.0–12.5 μM and 12.5–1000.0 μM, with correlation coefficients of 0.995 and 0.997, respectively. The limit of detection was determined to be 47 nM (S/N = 3). According to the calculated Hill coefficient (0.99), it can be concluded that the electrocatalytic process followed the Michaelis-Menten kinetic mechanism. The maximum catalytic current Im was 25 μA, while the apparent Michaelis-Menten constant Km was 1.425 mM. These findings indicated excellent electrocatalytic activity of the modified electrode towards oxidation of EP. The developed biosensor successfully detected EP in spiked mouse serum as well as epinephrine hydrochloride injection with high selectivity, sensitivity, stability, and accuracy.

Adrenaline biosensors based on r Go/Ag nanocomposites functionalized textiles using advanced electron beam irradiation technique

This study developed flexible textile biosensors based on rGO/Ag nanocomposite to detect adrenaline (epinephrine). Reduced graphene oxide (rGO) and Ag nanoparticles (NPs) were obtained in a single step using the electron-beam irradiation technique, a rapid, efficient, plain, ecofriendly, and easily scalable procedure. The nanocomposites’ properties were characterized by ultraviolet–visible-light spectroscopy, Fourier-transform infrared spectroscopy, scanning electron microscopy, cyclic voltammetry, and electrochemical impedance spectroscopy. Furthermore, the obtained sensors’ electrochemical behaviors of epinephrine were investigated using square wave voltammetry (SWV), linear sweep voltammetry, and differential pulse voltammetry methods. The optimum experimental conditions included pH 7, phosphate borate buffer, accumulation time of 100 s, accumulation potential of 0.4 V, and a scan rate of 100mV/s. In addition, the anodic peak currents of epinephrine by SWV were 16.33 and 13.9 µA for rGO/AgNP/cotton and rGO/AgNP/polyester, respectively. The fabricated flexible textile biosensors exhibited high sensitivity and strong catalytic activity for epinephrine detection. Under optimal testing conditions, in the range of 0.5–100.0 µL, two detection lines and a low limit of detection (LOD) of 9.73 nM (S/N = 3) for epinephrine were obtained for cotton and polyester biosensors. Two wide detection ranges were observed at 0.5–40.0 µL for cotton biosensors, whereas there was a lower LOD of 3.05 nM (S/N = 3) at 1.0–30 µL for polyester biosensors. Overall, the constructed electrode can serve as a promising analytical sensor for adrenaline determination in pharmaceutical and biological samples.

Simultaneous electrochemical determination of epinephrine and acetylcholine using modified screen printed electrode

Electrochemical behaviors of epinephrine and acetylcholine were investigated, using cyclic voltammetry, on the Ag-ZnO modified screen-printed electrode (Ag-ZnO/SPE). Ag-ZnO nanoplates showed excellent electrocatalytic activity toward the oxidation of epinephrine and acetylcholine compared with bare SPE in 0.1 M PBS. Under the optimized experimental conditions, a linear response obtained in the range of 0.13 to 450.00 μM with detection limit of 0.04 μM for epinephrine. Ag-ZnO/SPE exhibits good stability, reproducibility and repeatability, and the method has been successfully applied for detection of epinephrine and acetylcholine in their pharmaceutical and biological samples with satisfactory recovery.

Electrochemical Detection of Epinephrine at Organic Conducting Polymers Electrodes

In this paper, a rapid and sensitive modified electrode for the determination of Epinephrine (EP) is proposed. In this study, active compound EP was determined from commercial drug form based on electrochemical oxidation properties at various electrodes by voltammetric methods. Electrodes modified by the electrodeposition of conducting organic polymers such as poly(3-methylthiophene, PMT), polypyrrole (PPY) and polyaniline (PAN) were used as chemical sensors for voltammetric analysis and flow injection detection of EP. The electrochemical behavior of EP at conducting polymer electrodes was compared and the effects on behavior of electrolyte type and its pH and the film thickness were systematically examined. The results showed that the proposed modified surface catalyzes the oxidation of EP. Electrocatalytic efficiency decreases in order of PMT > PPY > PAN. Voltammetric peak positions were affected by the nature of the electrolyte and its pH. Also, the effect of increasing film thickness was to observe increased peak heights for oxidation potential of EP. The best results for the determination of EP were obtained by DPV in Na2SO4 (pH 2.0) and PMT electrodes. Polymer coated electrodes were also used in an amperometric detector for flow injection analysis of EP. The responses of the polymer electrode were 5–15 times larger as compared to those of bare platinum. PMT showed improved performance as an amperometric detector for flow injection analysis systems over other types of polymer electrodes. Detection limits as low as 1× 10–9 M were achieved using the PMT, compared to 1 × 10–6 M using platinum electrodes.

Development, validation and enzyme kinetic evaluation of multi walled carbon nano tubes mediated tyrosinase based electrochemical biosensing platform for the voltammetric monitoring of epinephrine

Epinephrine (EP) is one of the key neurotransmitter, which plays a vital role in the central nervous system. Current research report designates the development of biosensor based on the modification of glassy carbon electrode (GCE) with multi walled carbon nano tubes (MWCNTs) followed by drop casting of Tyrosinase (Ty) enzyme (Ty/MWCNTs/GCE) towards the sensitive monitoring of EP. The electrochemical behavior of EP at Ty/MWCNTs/GCE biosensor was examined and the redox mechanism was proposed. The developed Ty/MWCNTs/GCE was characterized by electrochemical techniques such as cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and tafel plot studies. The influence of pH of phosphate buffer solution (PBS) on the electrochemical redox behavior of EP was observed and pH-7.0 was identified as optimal pH value. The electrochemical kinetic parameters such as heterogeneous rate constant, diffusion coefficient and charge transfer coefficient values were evaluated. The limit of detection and limit of quantification values were evaluated. The low apparent Michaelis – Menten constant (Kmapp) was determined as 0.159 mM, demonstrating the immense catalytic activity of Ty enzyme. Repeatable, reproducible and stable nature of the fabricated Ty/MWCNTs/GCE was successfully examined. Finally, the developed biosensor was tested for the practical application in quantification of EP in human serum samples.

Voltammetric and amperometric sensors for determination of epinephrine: A short review (2013-2017)

The present review focuses on voltammetric and amperometric methods applied for determination of epinephrine (EP) in last five years (2013-2017). Occurrence, role and biological importance of EP, as well as non-electrochemical methods for its assessment, are firstly reviewed. The electrochemical behavior of EP is then illustrated, followed by a description of the voltammetric and amperometric methods for EP content estimation in various media. Different methods for development of electrochemical sensors are reviewed, starting from unmodified electrodes to different composites incorporating carbon nanotubes, ionic liquids or various mediators. From this perspective, the interaction between functional groups of the sensor material and the analyte molecule is discussed, as it is essential for analytical characteristics obtained. The analytical performances of the voltammetric or amperometric chemical and biochemical sensors (linear range of analytical response, sensitivity, precision, stability, response time, etc.) are highlighted. Numerous applications of EP electrochemical sensors in fields like pharmaceutical or clinical analysis where EP represents a key analyte, are also presented.

Electrochemical determination of epinephrine, uric acid and folic acid using a carbon paste electrode modified with novel ferrocene derivative and core–shell magnetic nanoparticles

The purpose of the current research was to construct an intermediate (2-(4-Ferrocenyl-[1,2,3]triazol-1-yl)-1-(naphthalen-2-yl) ethanone (2FTNE)) and a magnetic core–shell manganese ferrite nanoparticle (CMNP) to synthesis a modified carbon paste electrode (CPE). The electrochemical behavior of epinephrine (EP) was assessed by cyclic voltammetry and measured by square wave voltammetry by exposing to uric acid (UA) and folic acid (FA). High electrocatalytic activity for EP oxidation was seen in the 2FTNECMNP-modified CPE (2FTNEMCNPPE) compared to only CPE- and MCNP-modified CPE. The oxidation peak current of EP was linear within the range of 0.05–60 μM and its correlation coefficient was 0.999. The limit of detection was calculated at 0.016 μM for EP based on three times the standard deviation (3Sb) of the blank. According to the results, high selectivity, proper stability and good reproducibility was observed for the 2FTNEMCNPPE that detected EP, UA and FA successfully in an EP ampule, a folic acid tablet and urine samples, introducing 2FTNEMCNPPE with high capacity to develop the electrochemical sensors.

Anodic Voltammetry of Epinephrine at Graphene-Modified Conductive Diamond Electrodes and Its Analytical Application

The electrochemical behavior of epinephrine at graphene-modified boron-doped diamond (GR/BDD) electrodes was studied in phosphate buffer solution within pH range from 4.6 to 10. Cyclic voltammograms, recorded for GR/BDD and boron-doped diamond (BDD) at pH 7, attest that, in the first case, the peak associated to the oxidation of epinephrine to adrenalinquinone is negatively shifted by around 350 mV and much sharper and higher. It appears that the presence of the graphene layer promotes the overall oxidation process. Additional investigations carried out at different pH, point out that the best sensitivity of GR/BDD toward epinephrine oxidation is obtained at pH 7. The calibration plot at pH 7 exhibited a certain decrease of the sensitivity from a rather high value 3.00 μA cm−2 μM−1 within the concentration range 1 μM–10 μM to a satisfactory one of 0.45 μA cm−2 μM−1 at higher epinephrine content, suggesting that GR/BDD electrode may be used for trace analysis. Epinephrine detection in the presence of uric acid, with relevance for the detection of biological compounds, can be achieved at relatively low or high pH, in which cases, two peaks situated at 0.229 V and 0.356 V, corresponding to epinephrine and uric acid oxidation, are evidenced.

Voltammetric determination of epinephrine and xanthine based on sodium dodecyl sulphate assisted tungsten trioxide nanoparticles

This work reports the voltammetric determination of epinephrine (EP) and xanthine (XA) using gamma irradiated tungsten trioxide (WO3) nanoparticles. WO3 NPs synthesized by anionic surfactant sodium dodecyl sulphate (SDS) assisted template method was subjected to gamma rays under different doses (0-150 kGy). The experimental results revealed that the 50 kGy irradiation on SDS-WO3 NPs led to significant changes in crystallite size and morphology which enriched its electrocatalytic activity greatly. The electrochemical behaviors of EP and XA at 50 kGy gamma irradiated SDS-WO3 modified glassy carbon electrodes (GCE) were studied by cyclic voltammetry and differential pulse voltammetry. The outcomes confirmed that the proposed electrode demonstrate excellent electrocatalytic activity towardsthe oxidation of EP and XA in phosphate buffer solution (PBS, pH 7.0). The fabricated electrode possess lowest detection limit of 1.8nM and 2.2nM for EP and XA respectively with the very wide dynamic linear range of 9nM to 1mM. Finally, the modified sensor was successfully implemented to detect EP and XA in the human serum samples with excellent selectivity, good stability and reproducibility.

Epinephrine electrochemical sensor based on a carbon paste electrode modified with hydroquinone derivative and graphene oxide nano-sheets: Simultaneous determination of epinephrine, acetaminophen and dopamine

Abstract In this paper, an electrochemical sensor was constructed for determination of epinephrine based on carbon paste electrode (CPE) modified with graphene oxide (GO) and 2-(5-Ethyl-2,4-dihydroxyphenyl)-5,7-dimethyl-4H-pyrido[2,3-d][1,3]thiazine-4-one (EDDPT) as modifiers. The modified electrode was applied as an electrochemical sensor for oxidation of epinephrine (EP). Under the optimum conditions, the over potential of EP oxidation decreased about 279 mV at the modified CPE more than a non-modified CPE. Electrochemical behavior of EP was investigated on the fabricated electrode by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods, and some kinetic parameters of EP were obtained, too. The linear range and the detection limit for EP were found to be 1.5–600.0 μM and 0.65 μM (based on 3 s/m), respectively using the EDDPT/GO/CPE sensor and the differential pulse voltammetry (DPV) method. Also, the designed electrochemical sensor was applied to determine EP in the drug sample and simultaneous determination of epinephrine (EP), acetaminophen (AC) and dopamine (DA) in human serum solutions.

A novel graphene-chitosan-Bi2O3 nanocomposite modified sensor for sensitive and selective electrochemical determination of a monoamine neurotransmitter epinephrine

A novel sensitive electrochemical sensor has been developed by modification of glassy carbon electrode (GCE) with graphene (GRP), chitosan (CHIT), and bismuth oxide (Bi2O3) nanoparticles. The morphological characteristics of nanocomposite (GRP-CHIT-Bi2O3 or GCB) were studied by scanning electron microscope and atomic force microscopy. The electrochemical behavior of epinephrine at nanocomposite modified GCE (GCB/GCE) was investigated in pH 7.4 phosphate buffer solution using cyclic voltammetry and square wave voltammetry. GCB/GCE showed an enhancement in the current response as compared to bare GCE. Electrochemical impedance spectra showed a reduction of charge transfer resistance and higher electrocatalytic behavior of the sensor. The electrooxidation process of epinephrine at the modified sensor was found to be diffusion controlled. GCB/GCE showed a linear response to epinephrine in the range 100 to 500 nM. The limit of detection and limit of quantification were found to be 3.56 and 11.85 nM, respectively, which is lower than many other sensors reported for epinephrine in literature. The modified sensor showed high sensitivity (1.3 nA/nM) and selectivity for epinephrine. The method was employed for quantification of epinephrine in pharmaceutical formulation and human blood serum samples.

Influence of acidity and auxiliary electrode reaction on the oxidation of epinephrine on the pre-anodized carbon paste electrode

In this paper, the influence mechanisms of the solution acidity and the auxiliary electrode reaction on the oxidation peak current of epinephrine (EP) were researched on a pre-anodized carbon paste electrode in a “U” shape electrolytic cell. By changing the solution acidity in the auxiliary electrode electrolytic cell (AEEC) or the working electrode electrolytic cell (WREEC), the electrochemical behaviors of EP in the WREEC was investigated by cyclic voltammetry. It is found that the magnitude of the oxidation peak current of EP is closely related to the solution acidity for both WREEC and AEEC. The effects of the supporting electrolyte, the reduction reaction at the auxiliary electrode, distribution of the EP species and the molecular configuration of EP on the oxidation peak current of EP were also explored. Furthermore, the reaction mechanisms for both cathode and anode were proposed and interpreted. With the provided electrode reaction mechanisms, optimized pH value can be chosen based on the distribution coefficients for future related researches. Satisfactory results have been achieved for the determination of EP in injection using these mechanisms.

Determination of Epinephrine by Graphene/Platinum Nanoparticle Hybrid Membrane Modified Electrode

Graphene / platinum nanoparticles hybrid membrane modified electrode was prepared by cyclic voltammetry( CV). The electrochemical behaviors of epinephrine( EP) were studied on this modified electrode,and an electrochemical method for determination of EP was developed. The morphology and the electrochemical properties of the modified electrode were characterized by scan electron microscopy( SEM) and cyclic voltammetry,respectively. The conditions that influence the electrochemical properties of the modified electrode during the preparation processes and the conditions for determination of EP were optimized.Experimental results show that the modified electrode has excellent catalytic properties for the redox of EP. In the Na2HPO4-citric acid buffer solution( p H = 5. 0),the oxidative peak current of EP is linear with its concentration in the range of 4. 4 × 10-8~ 2. 2 × 10-6mol / L. The linear regressive equation is ipa( 10 A) =0. 0753c( mol / L) + 3. 7653 × 10-5with r = 0. 9989,and the detection limit of 2. 0 × 10-9mol / L( S / N = 3).The modified electrode shows good reproducibility,high sensitivity and selectivity. It could be used for determination of the content of EP in real samples.

Gold nanoparticles/polyaniline Langmuir–Blodgett Film modified glassy carbon electrode as voltammetric sensor for detection of epinephrine and uric acid

Gold nanoparticles/polyaniline nanocomposite thin film was deposited onto the surface of glassy carbon electrode(GCE) by Langmuir-Blodgett(LB) technology to fabricate a new voltammetric sensor (GNPs/PAn-LB GCE) for epinephrine(EP) and uric acid(UA) detection. Cyclic voltammetry, electrochemical impedance spectroscopy and atomic force microscopy were employed to study the characteristic of the GNPs/PAn-LB film. Electrochemical behaviors of EP and UA at the modified electrode were investigated in pH 6.6 phosphate buffer solutions. A sensitive electroanalytical method for simultaneous determination of EP and UA was proposed with high precision and good reproducibility.

Synthesis and characterization of ordered mesoporous carbon as electrocatalyst for simultaneous determination of epinephrine and acetaminophen

In this research, we report an easy method for synthesis of ordered mesoporous carbon (OMC) with hexagonal arrays of tubes (CMK-5). The synthesized OMC was characterized using X-ray diffraction (XRD), scanning electronic microscopy (SEM) and nitrogen sorption isotherms techniques. Due to the large surface area and high conductivity of OMC, OMC-modified glassy carbon (OMCs/GC) electrode was prepared. The unique electrochemical activity of OMCs/GC electrode was illustrated using cyclic voltammetry (CV) and electron impedance spectroscopy (EIS) in which OMC showed a faster electron transfer rate, as compared with glassy carbon electrode. The electrochemical behavior of epinephrine (EN) and acetaminophen (AP) at OMC/GC electrode was also investigated using cyclic voltammetry. The OMC/GC electrode exhibited high electrocatalytic activities toward oxidation of EN and AP and displayed good voltammetric peak separation between them. In differential pulse voltammetry technique, both EN and AP give sensitive oxidation peaks at 120 mV and 320 mV, respectively. Therefore, investigated method was applied for simultaneous determination of EN and AP. AP and EN give linear response over the range of 0.2–15 μM and 4–100 μM, respectively. The lower detection limits were found to be 0.07 μM for AP and 0.94 μM for EN.

Sensitive voltammetric determination of epinephrine in the presence of acetaminophen at a novel ionic liquid modified carbon nanotubes paste electrode

A novel ionic liquid modified carbon nanotubes paste electrode (IL/CNTPE) had been fabricated by using hydrophilic ionic liquid 1-methyl-3-butylimidazolium bromide [MBIDZ]Br as a new binder. The IL/CNTPE was characterized by a scanning electron microscope and voltammetry. Electrochemical behavior of epinephrine (EP) at the IL/CNTPE had been investigated in pH 7.0 phosphate buffer solution (PBS) by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), chronoamperometry (CA) and differential pulse voltammetry (DPV). The experimental results suggested that the modified electrode exhibited an electrocatalytic activity toward the redox of EP. The electron transfer coefficient, diffusion coefficient, and charge transfer resistant (Rct) of EP at the modified electrode were calculated. The IL/CNTPE showed an excellent electrocatalytic activity for selective detection of EP in the presence of acetaminophen (AC) by using DPV. Detection limit of EP and AC was found to be 0.09 and 0.5μM respectively. The proposed sensor was successfully applied for the determination of EP and AC in human urine, pharmaceutical, and serum samples.

Immobilization of DNA on a glassy carbon electrode based on Langmuir–Blodgett technique: application to the detection of epinephrine

A double-stranded (ds) DNA-octadecylamine Langmuir–Blodgett film was attached to the surface of glassy carbon electrode (GCE) to create a novel voltammetric sensor (DNA-LB/GCE) for epinephrine (EP). Atomic force microscopy and electrochemical impedance spectroscopy were employed to study the characteristic of the DNA-LB film. The electrochemical behavior of EP at the modified electrode was investigated in pH 6.0 phosphate buffer solutions by cyclic voltammetry and amperometric methods. Compared with bare GCE, the DNA-LB/GCE sensor demonstrated an electrocatalytic effect on the oxidation of EP. In addition, the sensor shows excellent selectivity for EP detection, being free of interference from excess ascorbic acid and uric acid, and the method was also applied successfully to detect EP in the human urine samples.

Simultaneous electrochemical determination of epinephrine and uric acid at 1-butyl-4-methyl-pyridinium tetrafluroborate ionic liquid modified carbon paste electrode: A voltammetric study

An ionic liquid (IL) film 1-butyl-4-methyl-pyridinium tetrafluroborate modified carbon paste electrode (BMPTB/CPE) was fabricated and the electrochemical behavior of epinephrine at the modified electrode was investigated by cyclic voltammetric and differential pulse voltammetric techniques. A well-defined oxidation peak was observed at 0.21 V and the significant increase in peak current at modified carbon paste electrode compared to bare carbon paste electrode was obtained. The effect of scan rate on the oxidation of epinephrine was examined and it was found that the anodic peak current was proportional to the concentration of epinephrine in the range from 0.5 × 10 − 5 to 4.5 × 10 − 5 M. The BMPTB/CPE showed significantly higher sensitivity, and selectivity and used for the simultaneous determination of epinephrine and uric acid. The advantages of this biosensor showed simplicity, inherent stability and ability for simultaneous determination without using any other separation systems. The analytical performance of this biosensor has been evaluated for detection of epinephrine injection in serum as real sample.

A novel poly(taurine) modified glassy carbon electrode for the simultaneous determination of epinephrine and dopamine

A novel taurine modified glassy carbon electrode was prepared by electropolymerization method. The electrochemical behaviors of epinephrine (EP) and dopamine (DA) at the modified electrode were studied by cyclic voltammetry. The modified electrode exhibited enhanced sensitivity and excellent electrochemical discrimination to DA and EP. The cathodic peaks of the two species were well-separated with a potential difference of about 390 mV, so the poly(taurine) modified electrode was used for simultaneous voltammetric measurement of EP and DA by differential pulse voltammetry. Under the optimum conditions, the cathodic peak currents were linear to concentrations of EP and DA in the range of 2.0 × 10 −6 to 6.0 × 10 −4 mol L −1 and 1.0 × 10 −6 to 8.0 × 10 −4 mol L −1, respectively. The detection limits for EP and DA were 3.0 × 10 −7 and 1.0 × 10 −7 mol L −1, respectively. Because the oxidation of ascorbic acid (AA) is an irreversible reaction at modified electrode, the interference of AA for determining EP and DA was eliminated. The modified electrode has been satisfactorily used for the simultaneous determination of EP and DA in pharmaceutical injections.

Electrochemistry and determination of epinephrine using a mesoporous Al-incorporated SiO 2 modified electrode

The potential application of Al-incorporated mesoporous SiO 2 (denoted as Al-MCM-41) in electrochemistry as a novel electrode material was investigated. The peak currents of K 3[Fe(CN) 6] remarkably increase and the peak potential separation obviously decreases at the mesoporous Al-MCM-41 modified carbon paste electrode (CPE). These phenomena suggest that the mesoporous Al-MCM-41 modified CPE possesses larger electrode area and electron transfer rate constant. Furthermore, the electrochemical behavior of epinephrine (EP) was investigated in different supporting electrolytes such as 0.01 mol L −1 HClO 4 and pH 7.0 phosphate buffer. It is found that the mesoporous Al-MCM-41 modified CPE exhibits catalytic ability to the oxidation of EP due to remarkable peak current enhancement and negative shift of peak potential. The electrochemical oxidation mechanism was also discussed. Finally, a novel electrochemical method was proposed for the determination of EP, which used to determine EP in urine samples.