Selective Determination Of Epinephrine Research Articles

Selective determination of epinephrine using electrochemical sensor based on ordered mesoporous carbon / nickel oxide nanocomposite

A nanocomposite of ordered mesoporous carbon/nickel oxide (OMC-NiO) was synthesized by hard-templating method. The nanocomposite remained ordered mesostructure and high surface area with the NiO nanocrystals embedded in the wall of the OMC. A sensitive sensor for electrochemical detection of epinephrine (EP) was developed with GCE modified by OMC-NiO nanocomposite. Cyclic voltammogram (CV) and differential pulse voltammetry (DPV) were used as the techniques to explore the electrochemical behavior of EP on OMC-NiO/GCE surface. The result showed that the electrode demonstrated better electrocatalytic performance to EP compared to that seen at OMC/GCE. Under the optimum condition, DPV measurements of the electrode response displayed a linear detection range for 8.0 × 10−7 to 5.0 × 10−5 M with a detection limit of 8.5 × 10−8 M (S/N = 3). It is worth noting that the electrocatalytic redox mechanism of EP on the electrode have studied through experiments and calculations (cyclic voltammetry and molecular electrostatic potential distribution). Moreover, the electrocatalytic behavior for the oxidation of EP and uric acid (UA) on OMC-NiO/GCE surface was investigated. The result showed that the sensor can be used to selectively determinate EP in the presence of an excesses of UA. Finally, the developed sensor was successfully applied to the determination of EP in spiked human blood serum and EP injection with satisfactory results.

A simple sonochemical assisted synthesis of nanocomposite (ZnO/MWCNTs) for electrochemical sensing of Epinephrine in human serum and pharmaceutical formulation

Herein, the electrochemical sensor was designed based on ZnO nanoparticles (NPs) and multi-walled carbon nanotubes (MWCNTs) for the sensitive and selective determination of Epinephrine (EP). ZnONPs was decorated on MWCNTs with the help of ultra-sonication to produce a nanocomposite (ZnO/MWCNTs), which was later dispersed on the surface of glassy carbon electrode (GCE). The morphology and characterization of nanocomposite were examined by using HR-TEM, FE-SEM, FT-IR and EDS techniques. The performance of ZnO/MWCNTs/GCE was evaluated by using various electrochemical methods such as CV, DPV and EIS. ZnO/MWCNTs/GCE showed good electrocatalytic activity in terms of EP oxidation by giving much higher peak currents than those obtained at bare GCE and MWCNTs/GCE. The fabricated sensor demonstrated good selectivity, reproducibility and stability. The performance of the fabricated sensor was good in terms of evaluating the kinetic parameters such as heterogeneous rate constant and the number of electrons involved in the reaction. The analytical performance of the developed method towards the determination of EP endowed linear dynamic range from 0.4 μM to 2.4 μM with a detection limit of 0.016 μM. The practical application of the fabricated sensor was demonstrated by determining EP in spiked human blood serum and adrenaline titrate injection samples.

Adsorption Studies and Selective Determination of Epinephrine at Glycerol-Clay Modified Glassy Carbon Electrode

Adsorption Studies and Selective Determination of Epinephrine at Glycerol-Clay Modified Glassy Carbon Electrode

Selective analysis of epinephrine in the presence of uric acid by using an amplified electrochemical sensor employing a gold nanoparticle decorated cysteic acid film

In the present work, an effective electrochemical sensor for the rapid and selective determination of epinephrine (EP) in the presence of uric acid (UA) based on a glassy carbon electrode (GCE) modified with gold nanoparticles (AuNPs) and cysteic acid was applied.

Selective Determination of Epinephrine in the Presence of Ascorbic Acid on a Carbon Nanotubes Modified Electrode Based on the Enhancement Effects of the Hexadecyl Trimethyl Ammonium Bromide

Selective Determination of Epinephrine in the Presence of Ascorbic Acid on a Carbon Nanotubes Modified Electrode Based on the Enhancement Effects of the Hexadecyl Trimethyl Ammonium Bromide

Selective Determination of Epinephrine in the Presence of Ascorbic Acid Using a Glassy Carbon Electrode Modified with Graphene

A graphene-modified glassy carbon electrode was fabricated via a drop-casting method, and applied to the electrochemical detection of epinephrine. The capacity of the graphene-modified glassy carbon electrode for the selective detection of epinephrine was confirmed in a sufficient amount of ascorbic acid (2 mmol L(-1)) by cyclic voltammetry. The modified electrode showed an excellent electrocatalytical effect on the oxidation of epinephrine. A pair of well-defined redox waves were observed in voltammograms of epinephrine in a phosphate buffered solution (pH 4.0). The peak potentials of epinephrine remained unchanged, and the oxidation peak currents showed a linear relation versus the epinephrine concentration in the range of 3.85 × 10(-7) - 1.31 × 10(-5) mol L(-1) and 1.31 × 10(-5) - 1.09 × 10(-4) mol L(-1) with a correlation coefficient as follows: i(pa1) = -4.25 × 10(-6) - 1.99c (mol L(-1)), R(1) = 0.9953; i(pa2) = -4.31 × 10(-5) - 0.315c (mol L(-1)), R(2) = 0.9988. Detection limit is estimated to be 8.9 × 10(-8) mol L(-1). Graphene-modified glassy carbon electrode was applied to epinephrine sample analysis, and the results were in good agreement with the standard values.

Selective Determination of Epinephrine in the Presence of Ascorbic Acid and Dopamine at Silver Doped Polyglycine Modified Electrode

Selective Determination of Epinephrine in the Presence of Ascorbic Acid and Dopamine at Silver Doped Polyglycine Modified Electrode

Selective Determination of Epinephrine in the Presence of Ascorbic Acid and Dopamine Using a Glassy Carbon Electrode Modified with Valine

A glassy carbon electrode (GCE) modified with valine was used for the sensitive volt metric determination ofepinephrine (EP). The electrochemical response characteristics of the modified electrode toward EP, ascorbic acid (AA)and dopamine (DA) were investigated by cyclic voltammetry (CV). The results show an efficient catalytic activity ofthe electrode for the electro-oxidation of EP, which leads to an improvement to the reversibility of the electroderesponse. The effect of pH and potential sweep rate on the mechanism of the electrode process was investigated. Themodified electrode exhibits an efficient electron mediating behavior along with well-separated oxidation peaks for EP,AA, and DA. Under the optimum pH of 7.0 in phosphate buffer solution(PBS), the CV anodic peak current showed alinear relation versus EP concentration in the range of 4.5×10-6~1.0×10-5mol·L-1 and 1.0×10-5~1.4×10-4 mol·L-1, withcorrelation coefficients of 0.9997 and 0.9942. The detection limit is 7.6×10-7 mol·L-1. High sensitivity and selectivity,submicromolar detection limit, high reproducibility, along with ease of preparation and regeneration of the electrodesurface by simple polishing make this method suitable for the determination of EP in pharmaceutical and clinicalpreparations.

Nanomolar and Selective Determination of Epinephrine in the Presence of Norepinephrine Using Carbon Paste Electrode Modified with Carbon Nanotubes and Novel 2-(4-Oxo-3-phenyl-3,4-dihydro-quinazolinyl)-N′-phenyl-hydrazinecarbothioamide

Nanomolar and Selective Determination of Epinephrine in the Presence of Norepinephrine Using Carbon Paste Electrode Modified with Carbon Nanotubes and Novel 2-(4-Oxo-3-phenyl-3,4-dihydro-quinazolinyl)-<i>N</i>′-phenyl-hydrazinecarbothioamide

Nanomolar and Selective Determination of Epinephrine in the Presence of Norepinephrine Using Carbon Paste Electrode Modified with Carbon Nanotubes and Novel 2-(4-Oxo-3-phenyl-3,4-dihydro-quinazolinyl)-N′-phenyl-hydrazinecarbothioamide

A novel modified carbon nanotube paste electrode of 2-(4-oxo-3-phenyl-3,4-dihydro-quinazolinyl)-N'-phenyl-hydrazinecarbothioamide (2PHC) was fabricated, and the electro-oxidation of epinephrine (EP), norepinephrine (NE), and their mixture has been studied using electrochemical methods. The modified electrode displayed strong catalytic function for the oxidation of EP and NE and resolved the overlap voltammetric response of EP and NE into two well-defined voltammetric peaks of about 240 mV with square wave voltammetry (SWV). A linear response in the range of (5 x 10(-8))-(5.5 x 10(-4)) M with a detection limit (S/N = 3) of 9.4 nM for EP was obtained.

Selective Electrochemical Epinephrine Sensor Using Self‐Assembled Monomolecular Film of 1,8,15,22‐Tetraaminophthalocyanatonickel(II) on Gold Electrode

AbstractThis article describes the highly sensitive and selective determination of epinephrine (EP) using self‐assembled monomolecular film (SAMF) of 1,8,15,22‐tetraamino‐phthalocyanatonickel(II) (4α‐NiIITAPc) on Au electrode. The 4α‐NiIITAPc SAMF modified electrode was prepared by spontaneous adsorption of 4α‐NiIITAPc from dimethylformamide solution. The modified electrode oxidizes EP at less over potential with enhanced current response in contrast to the bare Au electrode. The standard heterogeneous rate constant (k°) for the oxidation of EP at 4α‐NiIITAPc SAMF modified electrode was found to be 1.94×10−2 cm s−1 which was much higher than that at the bare Au electrode. Further, it was found that 4α‐NiIITAPc SAMF modified electrode separates the voltammetric signals of ascorbic acid (AA) and EP with a peak separation of 250 mV. Using amperometric method the lowest detection limit of 50 nM of EP was achieved at SAMF modified electrode. Simultaneous amperometric determination of AA and EP was also achieved at the SAMF modified electrode. Common physiological interferents such as uric acid, glucose, urea and NaCl do not interfere within the potential window of EP oxidation. The present 4α‐NiIITAPc SAMF modified electrode was also successfully applied to determine the concentration of EP in commercially available injection.

Selective Determination of Epinephrine in the Presence of Ascorbic Acid and Uric Acid by Electrocatalytic Oxidation at Poly(eriochrome Black T) Film-modified Glassy Carbon Electrode

An electropolymerized film of eriochrome black T (EBT) has been prepared at a glassy carbon electrode (GCE) by cyclic voltammetry (CV). The poly(EBT) membrane at GCE exhibits an excellent electrocatalytic activity towards the oxidation of epinephrine (EP), ascorbic acid (AA) and uric acid (UA) in acidic solution and reduced the overpotential for the oxidation of EP. The poly(EBT)-coated electrode could separately detect EP, AA and UA in their mixture with the potential differences of 180 and 160 mV for EP-AA and UA-EP, respectively, which are large enough to allow for determination of EP in the presence of AA and UA. Using differential pulse voltammetry, the peak current of EP recorded in pH 3.5 solution was linearly dependent on EP's concentration in the range of 2.5 - 50 microM. Due to its good selectivity and stability, the polymer-coated GCE was successfully applied to the determination of EP in real samples.