Electrochemical Oxidation Of Acetaminophen Research Articles

Electrochemical Behavior and Ultrasensitive, Simple and Effective Voltammetric Determination of Acetaminophen Using Modified Glassy Carbon Electrode Based on 4‐Hydroxyquinoline‐3‐carboxylic Acid

AbstractAn electrochemical oxidation of acetaminophen (ACOP) has been successfully performed by using glassy carbon electrode covered with 4‐hydroxyquinoline‐3‐carboxylic acid (4HQ3CA) to reinforce electrode's feature. To characterize the modified electrode (4HQ3CA/GC), electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and Fourier transform infrared spectroscopy (FT‐IR) techniques were used. The finding optimum conditions (supporting electrolyte, pH) and the electrochemical determination studies were performed with differential pulse voltammetry (DPV). It was decided that the supporting electrolyte medium suitable for ACOP determination was Britton‐Robinson (BR) buffer and the effect of pH change on the oxidation peak of ACOP in this media was investigated. The effect of changing scan rate on the oxidation peak of ACOP was examined and this study showed that the oxidation process of ACOP on the 4HQ3CA/GC modified electrode surface was diffusion and adsorption controlled process. A wide concentration range from 0.0025 μM to 141 μM with a limit of detection (LOD) of 5.98×10−10 M (3 s/m) was obtained. This prepared sensor was carried out for the determination of ACOP in pharmaceutical sample.

Electrochemical oxidation of acetaminophen and its transformation products in surface water: effect of pH and current density

Several studies have been conducted worldwide to develop effective and affordable methods to degrade pharmaceuticals and their metabolites/intermediates/oxidation products found in surface water, wastewater and drinking water. In this work, acetaminophen and its transformation products were successfully degraded in surface water by electrochemical oxidation using stainless steel electrodes. The effect of pH and current density on the oxidation process was assessed and the oxidation kinetics and mechanisms involved were described. Additionally, the results were compared with those obtained in acetaminophen synthetic solutions. It was found that conducting the electrochemical oxidation at 16.3 mA/cm2 and pH 5, good performance of the process was achieved and not only acetaminophen, but also its transformation products were totally degraded in only 7.5 min; furthermore, small number of transformation products were generated. On the other hand, degradation rates of acetaminophen and its transformation products in surface water were much faster (more than 2.5 times) and the reaction times much shorter (more than 4.0 times) than in synthetic solutions at all current densities and pH values evaluated. At pH 3 and pH 5, greater soluble chlorine formation due to the higher HCl amount used to acidify the surface water solutions could enhance the degradation rates of acetaminophen and its transformation products. However, constituents of surface water (ions and solids) could also have an important role on the oxidation process because at pH 9 (non-acidified solutions) the degradation rates were also much greater and the reaction times were much shorter in surface water than in acetaminophen synthetic solutions.

Electrochemical oxidation of acetaminophen in the presence of diclofenac and piroxicam - Synthesis of new derivatives and kinetic investigation of toxic quinone imine/drugs interactions

In this research, electrochemical oxidation of acetaminophen was investigated in the presence of steroidal anti-inflammatory drugs diclofenac and piroxicam by cyclic voltammetry and controlled-potential coulometry techniques. The results indicated that N-acetyl-p-benzoquinone-imine (NAPQI), produced by electrooxidation of acetaminophen, reacts with diclofenac and piroxicam, via the Michael addition reaction. Corresponding products were electrochemically synthesized in aqueous solutions using a carbon electrode in an undivided cell. These products were identified by spectroscopic methods (FT-IR, 1HNMR, 13CNMR and MS). The homogeneous rate constants (kobs), based on the suggested electrode mechanism (i.e. EC), were estimated by comparing the experimental cyclic voltammetric responses with those digital simulated results. A comparison of the estimated kobs for the reaction of electrochemically generated N-acetyl-p-benzoquinone-imine (NAPQI) with steroidal anti-inflammatory drugs revealed that kobs (piroxicam) > kobs(diclofenac) at biological pH.

Fabrication of platinum nitrogen-doped graphene nanocomposite modified electrode for the electrochemical detection of acetaminophen

An electrochemical sensor for the determination of acetaminophen (AC) was fabricated on glassy carbon electrode (GCE) modified with platinum nitrogen-doped graphene (Pt/NGr) nanocomposite. Electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and square-wave voltammetry (SWV) were performed to investigate the electrochemical behaviour of AC. From the electrochemical results, the synergy between platinum nanoparticles and nitrogen-doped graphene improved the interfacial electron transfer process, thus exhibited a higher catalytic performance towards the electrochemical oxidation of AC. A linear range between 0.05–90 μmol L−1 for the determination of AC was achieved with a limit of detection of 0.008 μmol L−1. The prepared sensor demonstrated acceptable reproducibility, stability and good selectivity in the presence of interferences such as ascorbic acid, p-aminophenol and dopamine. In addition, this method showed satisfactory results in commercial tablets.

Facile and clean electrochemical synthesis of new acetaminophen derivatives through electrochemical oxidation of acetaminophen in the presence of thiouracil derivatives

ABSTRACTThe electrochemical oxidation of acetaminophen (1a) is carried out in the presence of thiouracil derivatives (3a–c), as nucleophiles, in an acetate buffer solution (0.15 M, pH 5) mixed with Dimethylformamide (DMF) using cyclic voltammetry and coulometry under a constant potential. The results obtained indicate that N-acetyl-p-benzoquinone-imine derived from acetaminophen participates in a 1,4-Michael-type addition reaction with thiouracils to form the corresponding acetaminophen derivatives (4a–c) in good yields and with high purities using a facile, catalyst-free, and one-pot electrochemical method using three carbon electrodes in an undivided cell under mild conditions. The products obtained were characterized after purification by IR, 1H NMR, and 13C NMR spectroscopies, and by the elemental analysis method.

Polymeric Co(salen) scaffold for the electrochemical determination of acetaminophen in pharmaceutical sample

A polymeric Co(salen) (where salen = N,N′-bis(salicylidene)ethylenediamine) electrochemical sensing scaffold was prepared by electropolymerization of Co(salen) on glassy carbon (GC) electrode employing potentiodynamic method. The sensing scaffold, represented as GC/poly[CoII-S], has notable activity toward the electrochemical oxidation of acetaminophen in 0.1 M pH 7.0 phosphate buffer solution. Polymeric films with porous or net-like structures are normally expected to function as excellent platforms for electrochemical reactions. Accordingly in the present study, GC/poly[CoII-S] scaffold displays a perfect linear relationship for acetaminophen determination in the range of 0.5 to 5000 μM. The sensitivity and detection limit are calculated as 71 μA mM−1 and 0.3 μM, respectively. This new sensing scaffold displays high stability for more than 40 days. The reproducibility is measured based on the response of different scaffolds for 12 experiments which shows a relative standard deviation of 3.9 %. Further, GC/poly[CoII-S] is successfully applied for acetaminophen determination in a real sample.

Regioselective Green Electrochemical Approach to the Synthesis of Nitroacetaminophen Derivatives.

A regioselective green synthesis of nitroacetaminophen derivatives was carried out by electrochemical oxidation of acetaminophen, N-(2-hydroxyphenyl)acetamide, and 1-(4-(4-hydroxyphenyl)piperazin-1-yl)ethanone in the presence of nitrite ion as a nucleophile. The present work has led to the development of a reagentless green and facile electrochemical method for the synthesis of some nitroacetaminophen derivatives.

Sensitive Detection of Acetaminophen with Graphene-Based Electrochemical Sensor

Here we report on a high-performance electrochemical sensor for the sensitive detection of acetaminophen based on graphene, which was simultaneously electrochemically reduced and deposited onto a glassy carbon electrode (GCE). The electrocatalytic properties of the electrochemically reduced graphene (ERG) toward the oxidation of acetaminophen were analyzed via cyclic voltammetry (CV), differential pulse voltammetry (DPV) and chronoamperometry. For comparison, various ERG/GCEs were prepared with different electrodeposition cycles to optimize the amount of the ERG. Our experimental results showed that the optimized ERG/GCE possessed robust activity in the electrochemical oxidation of acetaminophen, leading to the development of highly sensitive electrochemical sensor for its detection. An extremely low detection limit of 2.13nM and a wide linear detection range of from 5.0nM to 800μM were achieved via the combination of the amperometric technique and DPV. The developed electrochemical sensor was further employed for the determination of acetaminophen in human serum, with excellent recovery, ranging from 96.08% to103.2%. The fabricated electrochemical sensor also demonstrated high selectivity, stability and reproducibility. The wide linear detection range obtained in this study for the detection of acetaminophen showed strong potential as a promising sensing technique for pharmaceuticals, in terms of quality control and in clinical laboratories for acetaminophen as relates to the determination of hepatotoxicity.

Electrochemical Oxidation of Acetaminophen in the Presence of Barbituric Acid Derivatives

Electrochemical oxidation of acetaminophen (1) in the presence of barbituric acid (2a), 1,3-dimethyl barbituric acid (2b), 2-thiobarbituric acid (2c) and 1,3-diethyl-2-thiobarbituric acid (2d) as nucleophiles in aqueous solution has been studied using cyclic voltammetry and controlled-potential coulometry. The results indicate that the p-quinone imine derived from electrooxidation of acetaminophen (1) participates in a Michael addition reaction with 2a-d to form the corresponding barbituric acid derivatives (7a-d). In addition, the homogeneous rate constants were estimated by comparing the experimental cyclic voltammetric responses with the digital simulated results. The electrochemical synthesis of 7a-d has been successfully performed in an undivided cell in good yields and purity at biological pH.

A Green Electrochemical Method for the Synthesis of Acetaminophen Derivatives

Electrochemical synthesis of new acetaminophen derivatives (4a-4c) has been carried out by the electrochemical oxidation of acetaminophen, N-(4-hydroxyphenyl)acetamide, in the presence of arylsulfinic acids (3a-3c) as nucleophiles in aqueous solution using cyclic voltammetry. The results revealed that the electrochemically generated N-acetyl-p-benzoquinone-imine (2) participates in Michael type addition reaction with arylsulfinic acids via an EC mechanism and is converted to the acetaminophen derivatives (4a-4c). The present work has led to the development of a facile and environmentally friendly reagent-less electrochemical method with high atom economy and safe waste under green conditions.

Electrochemical Oxidation of Acetaminophen and 4-(Piperazin-1-yl)phenols in the Presence of 4-Hydroxy-1-methyl-2(1H)-quinolone

A facile and one-pot electrochemical method for the synthesis of mono and disubstituted 1,4-benzoquinones generated from the electrochemical oxidation of 1-(4-(4-hydroxyphenyl)piperazin-1-yl)ethanone (1a), 4-(piperazin-1-yl)phenol (1b) and acetaminophen (8) in the presence of 4-hydroxy-1-methyl-2(1H)-quinolone (3) as nucleophile was reported. The results revealed that the electrochemically generated electrophiles derived from the oxidation of 1a, 1b and 8 participate in Michael-addition reactions with 3. In this work, we report the synthesis of mono and diquinolone substituted of 1,4-benzoquinone in good yields based on controlled potential condition at carbon electrode in a divided cell.

Determination of acetaminophen by electrochemical co-deposition of glutamic acid and gold nanoparticles

Abstract We developed an electrochemical sensor to detect acetaminophen by electrochemically co-depositing glutamic acid and gold nanoparticles on a single-walled carbon nanotube film (AuNP-PGA/SWCNT). Cyclic voltammetry indicated that the electrochemical oxidation of acetaminophen at the AuNP-PGA/SWCNT film electrode involved a two-electron, one-proton process and was pH dependent. Different pulse voltammograms of acetaminophen oxidation on the AuNP-PGA/SWCNT film electrode yielded a well-defined oxidation peak at 360 mV in 0.1 M phosphate buffered saline buffer (pH 7.2) with linear calibration from 8.3 to 145.6 μM ( R 2 = 0.997). The detection limit was estimated to be 1.18 μM. The proposed sensor is stable and reproducible from 1.15 to 5.21% with a relative standard deviation of 3.56%. The AuNP-PGA/SWCNT film electrode was able to detect acetaminophen in the presence of interfering ascorbic acid; two well-defined oxidation peaks, one for ascorbic acid at 0.15 V and the other for acetaminophen at 0.39 V, were detected. Furthermore, the fabricated sensor accurately measured the amount of acetaminophen in pharmaceutical samples. Together, these results indicate that our AuNP-PGA/SWCNT film is a promising platform for accurate and reproducible detection of acetaminophen.

IMMUNE RESPONSE IN SCHIZOPHRENIA: HOST-ENVIRONMENT INTERACTIONS

We developed an electrochemical sensor to detect acetaminophen by electrochemically co-depositing glutamic acid and gold nanoparticles on a single-walled carbon nanotube film (AuNP-PGA/SWCNT). Cyclic voltammetry indicated that the electrochemical oxidation of acetaminophen at the AuNP-PGA/SWCNT film electrode involved a two-electron, one-proton process and was pH dependent. Different pulse voltammograms of acetaminophen oxidation on the AuNP-PGA/SWCNT film electrode yielded a well-defined oxidation peak at 360 mV in 0.1 M phosphate buffered saline buffer (pH 7.2) with linear calibration from 8.3 to 145.6 μM (R2 = 0.997). The detection limit was estimated to be 1.18 μM. The proposed sensor is stable and reproducible from 1.15 to 5.21% with a relative standard deviation of 3.56%. The AuNP-PGA/SWCNT film electrode was able to detect acetaminophen in the presence of interfering ascorbic acid; two well-defined oxidation peaks, one for ascorbic acid at 0.15 V and the other for acetaminophen at 0.39 V, were detected. Furthermore, the fabricated sensor accurately measured the amount of acetaminophen in pharmaceutical samples. Together, these results indicate that our AuNP-PGA/SWCNT film is a promising platform for accurate and reproducible detection of acetaminophen.

Graphene Electrochemistry: Surfactants Inherent to Graphene Can Dramatically Effect Electrochemical Processes

AbstractSurfactants are routinely used in the production of graphene and additionally in their solubilisation with the aim of reducing the likelihood of coalescing. We demonstrate that surfactants, which are an inherent property of graphene, are a major contribution to the electrochemical performance. Using well characterised commercially available graphene we demonstrate that the surfactant may be detrimental in electrochemical processes, for example in the electrochemical oxidation of NADH, used prolifically as the basis of over 300 biosensors, and in the electrochemical oxidation of acetaminophen, an analgesic and antipyretic drug which requires routine monitoring in a plethora of areas. The use of control experiments in the form of surfactant modified carbon electrodes is particularly encouraged in de‐convoluting the origin of the electrochemical response of graphene modified electrodes.

Electrochemical evidences in oxidation of acetaminophen in the presence of glutathione and N-acetylcysteine

Electrochemical oxidation of acetaminophen has been studied in the presence of glutathione and acetylcysteine. Our results indicate that N-acetyl-p-benzoquinone-imine (NAPQI) participates in a catalytic reaction with glutathione and N-acetylcysteine. Also, the observed homogeneous rate constants of the reaction of NAPQI with glutathione and acetylcysteine were estimated.