Oxidation Of Paracetamol Research Articles

A highly sensitive sensor of paracetamol based on zinc-layered hydroxide-L-phenylalanate-modified multiwalled carbon nanotube paste electrode

A new zinc-layered hydroxide-L-phenylalanate (ZLH-LP)-modified multiwalled carbon nanotube (MWCNT) was prepared as a new material of paste electrode for the detection of paracetamol (PCM) in 1.0 × 10−1 M phosphate buffer solution and at pH 7.5. The electrochemical characterization of the MWCNTs/ZLH-LP paste electrode was characterized by square wave voltammetry, electrochemical impedance spectroscopy, and cyclic voltammetry while the morphology properties of the MWCNTs, ZLH-LP, and MWCNTs/ZLH-LP were investigated using transmission electron microscopy and scanning electron microscopy. Under optimized conditions, the MWCNTs/ZLH-LP paste electrode demonstrated an excellent electrocatalytic activity towards oxidation of PCM in the linear responses’ ranges from 7.0 × 10−7 M to 1.0 × 10−4 M (correlation coefficient, 0.996) with the limit of detection obtained at 8.3 × 10−8 M. As a conclusion, the MWCNTs/ZLH-LP paste electrode revealed good repeatability, reproducibility, and stability, and was found to be applicable for use in pharmaceutical tablet samples.

Dynamic cross-flow electro-Fenton process coupled to anodic oxidation for wastewater treatment: Application to the degradation of acetaminophen

In this work, we present an integrated dynamic cross-flow electro-Fenton (DCF-EF) system for the treatment of the pharmaceutical, acetaminophen (paracetamol), in aqueous medium. A carbonaceous electrocatalytic membrane was used as cathode, allowing the continuous production of H2O2 during EF in dynamic filtration mode. The transmembrane pressure (TMP) and current were the two driving forces of the system, whose influence strongly affected the global efficiency. It was found that H2O2 production from the electrochemical reduction of dissolved O2 was favoured at higher TMP values as a consequence of an increase of the O2 partial pressure, and higher H2O2 amounts entailed an increase in the efficiency of the process. Current also had a positive effect on H2O2 production and acetaminophen degradation and mineralization efficiencies up to an optimal value. Complete degradation of the drug and 44% mineralization were achieved under optimal conditions (2.0 bar and 100 mA). On the other hand, the results pointed out that the use of a Ti4O7 rod as counter electrode (anode) had an important contribution to the mineralization of the acetaminophen’s solutions owing to the formation of hydroxyl radicals (OH) on its surface, which highlighted the oxidative power of this anode material. The oxidation mechanisms involved during the process were assessed by electrochemical measurements with both electrodes (carbon membrane and Ti4O7 rod), and a degradation pathway for paracetamol oxidation was proposed based on the identification of the main aromatic and aliphatic degradation by-products. This DCF-EF process is presented as a potential alternative for water treatment and reuse in which the integration of membrane and electrochemical technologies brings together separation science and advanced oxidation.

A glassy carbon electrode modified with N-doped carbon dots for improved detection of hydrogen peroxide and paracetamol.

Nitrogen doped carbon dots (NCDs) were synthesized using a low temperature approach and used to modify a glassy carbon electrode (GCE) via dipping. The oxygen groups on the surface of the NCDs, and the charge delocalization of the NCDs warrant an excellent electrocatalytic activity of the GCE toward oxidation ofparacetamol (PA) andreduction of H2O2. PA and H2O2 were detected at 0.34V and -0.4V (bothvs. Ag/AgCl) using differential pulse voltammetry and amperometric I-T measurement, respectively. The modified GCE has a linear response to PA in the 0.5 to 600μM concentration range, and to H2O2 in the 0.05μM to 2.25mM concentration range. The detection limits are 157nM and 41nM, respectively. In our perception, the modified GCE holds promise for stable, selective and sensitive determination of PA and H2O2 in pharmaceutical analysis. Graphic abstract Nitrogen doped carbon dots (NCDs) were synthesized and used to modify a glassy carbon electrode. Surface functional groups on NCDs can trigger electrocatalytic reactions toward paracetamol oxidation and H2O2 reduction with high sensitivities.

Spectrophotometric determination of acetaminophen content of different brands of paracetamol tablets from Zliten

Paracetamol is a medicine compound commonly used as analgesic and antipyretic.1-5 It is classified as one of the drugs, known as aniline analgesics.6-9 It is used widely for the relief of a headache, other minor aches, pains, inflammations and a major ingredient in several cold and flu remedial combination drugs. While generally safe for use at a recommended dose, toxicity of paracetamol is the foremost cause of acute gastro intestinal problems.10-12 Paracetamol is considered to be the inhibitor of cyclooxygenase (COX), and recent reports suggest that it is highly selective for COX- 2. While it has analgesic and antipyretic properties comparable to those of aspirin or other NSAIDs, its peripheral anti-inflammatory activity is usually limited by several factors, one of which is high level of peroxides present in inflammatory lesions. It could be considered as one of Non-Steroidal Anti Inflammatory Drugs (NSAID).13-20 Many methods for its determination have been described in literature, including chromatography (RP - HPLC), chemometric - assisted spectrophotometric spectroscopy, Spectrophotometry and electrochemistry.Many spectrophotometric methods required complicated treatment, such as long period of heating (60-90 min) using concentrated acids as hydrolysis reagent. This work based on the oxidation of paracetamol by using Cr(VI) in presence of 6M sulfuric acid and 15 min heating at 80 °C as shown in scheme 1.

Rapid oxidation of paracetamol by Cobalt(II) catalyzed sulfite at alkaline pH

In this study we have investigated the efficiency Cobalt (II) (Co(II)) for the activation of sulfite ions following the oxidation of paracetamol used as model contaminants. Physico-chemical parameters that can impact the paracetamol degradation (pH, initial paracetamol concentration, Co(II)/S(IV) molar ratio, oxygen concentration) and contribution of various radicals were investigated in order to elucidate the chemical mechanism. Main results show that the pH is a key factor controlling the efficiency in the system Co(II)/Sulfite. Higher efficiency is observed for pH between 9.0 and 10.0. Increasing S(IV) concentrations, until 1 mM, slightly promoted the degradation of paracetamol. In fact, an excess of sulfite ions inhibits the reaction through the scavenging of SO4− and SO5−. Moreover, degradation efficiency drastically decreases from ∼ 85% to less than 5% in absence of oxygen. SO4− was confirmed to be the main oxidant responsible for the paracetamol degradation. For the first time we determined the second order rate constant between SO4− and paracetamol (1.33 ± 0.79 × 109 M−1 s−1 (at pH 5) and 6.14 ± 0.99 × 108 M−1 s−1 (at pH 11.0)). Moreover, radical-scavenging experiments also suggest the possible implication of SO5−. Hence, this work provides a precise understanding of the overall mechanism and a new promising strategy by using sulfite and transition metal such as Co(II) to promote organic compounds degradation in water under neutral and alkaline pH conditions.

Electrochemical Sensor for the Determination of Paracetamol at Carbamazepine Film Coated Carbon Paste Electrode

AbstractThe electrochemical behavior of paracetamol (PC) was investigated at carbamazepine (CBZ) film coated carbon paste electrode in 0.2 M PBS of pH 7.4 by cyclic voltammetric technique. The modified electrode was exhibited a good electrochemical activity towards the oxidation of paracetamol, which results in a noticeable improvement of the peak currents and feasible oxidation as compared to the bare carbon paste electrode. Under optimal experimental conditions the electrochemical response to PC was linear in the concentration range from 1.0×10−4M to 3.94×10−4M with a detection limit of 0.24 μM by cyclic voltammetric technique. The sensitivity, long-term stability, reproducibility was shown by the modified electrode. Finally, the proposed method was successfully applied to determine PC in pharmaceutical samples.

Voltammetric determination of paracetamol at NiO nanoparticles-modified carbon paste electrode in bulk and tablet dosage forms

Nickel oxide (NiO) nanoparticles were synthesized by a rapid method and well characterized. The nanoparticles were then used with graphite powder to prepare modified carbon paste electrode (CPE/NiO) for electrocatalytic oxidation of paracetamol (AC). The CPE/NiO showed higher electrocatalytic activity than nickel rod electrode in electrocatalytic oxidation of AC in alkaline media. The assay of AC, mechanism and kinetics of the electrooxidation process were investigated by cyclic voltammetry and chronoamperometry. The catalytic rate constant and the charge transfer coefficient of AC electrooxidation by the active nickel species and the diffusion coefficient of AC were also reported. The linear dependence of the peak current on the concentration of the AC was observed in the range 2–14 mM. This procedure was successfully applied to the determination of AC in tablets. The results showed sufficient precision, accuracy and achieved a mean recovery of 97.2% (RSD = 6.7%).

نظام جديد لتقنية اندماج المناطق في التحليل بالحقن الجرياني المستمر واستخدام مطياف مصنع محليا لتقدير عقار الباراسيتامول

The unit is designed IT system integration areas in flow injection analysis together with the device careful photometer and that means measuring the complex color when a wavelength of 508 nm. Estimation method was used paracetamol drug through drug paracetamol oxidation using iron (III) converted into iron (II) and the interaction of iron (II) with reagent 1:10- Phenanthroline and using a buffer solution has been studying the chemical and physical variables to get the best results. Calibration curve is subject to the law of Bear - Lambert within the range (0.3-1.2) m

Wet air oxidation of paracetamol over precious metal/Ti mesh monolith catalyst

Abstract The catalytic wet oxidation of paracetamol (PAR) was tested with Pt, Ru, Ir containing Ti monoliths measuring COD, TOC and TN conversion and compared with that of the non-catalytic reaction. The decrease of PAR concentration during reaction was followed by UV–vis spectrometry also. The catalysts were characterized by XPS, PGAA, TPR and SEM-EDX. The monometallic Pt and Ru/Ti catalysts were the most active, even below 150 °C. RuO 2 /Ti had the highest specific activity. After 100 h reaction time the Pt loss was 23%, while the RuO 2 /Ti kept its Ru content. The RuO 2 /TiO 2 composite formation explains the highest activity and stability.

A new droplet-based polymeric banana electrochemical biosensor for analysis of one microliter solution of paracetamol

Modern researches and also the laboratories increasingly need the methods to measure the small volumes as microliter of analytical samples for determination of various analytes with a high accuracy. An electrochemical biosensor based on a modified carbon paste electrode with hydrogel as an absorbent polymeric matrix and banana as a source of polyphenol oxidase was constructed and it was used for determination the concentration of paracetamol in one microliter volume of solution. The electrochemical oxidation of paracetamol was studied by cyclic voltammetry and square wave voltammetry. The effective parameters on the voltammetric response of the constructed biosensor were optimized. The results obtained by cyclic voltammetry revealed that the banana-hydrogel carbon paste electrode shows a higher current response compared to a banana carbon paste electrode and hydrogel carbon paste electrode. Because of high absorption property of hydrogel, the proposed electrode has the capability to measure only one μL of sample solution, which is very important and considerable property for limited volumes of sample solutions. The modified electrode also exhibits a low detection limit (1.6μM) with a good linear range (10–250μM) and it has a good reproducibility and stability in both basic and acidic environments even in the presence of the enzyme and a long life time (20days) for measurement of paracetamol in solutions.

Nanostructured Hexacyanoferrate Intercalated Ni/Al Layered Double Hydroxide Modified Electrode as a Sensitive Electrochemical Sensor for Paracetamol Determination

AbstractAn electrochemical sensor for paracetamol (PC) based on the hexacyanoferate(III) intercalated Ni−Al layered double hydroxide (Ni−Al−HCF) was presented. The as‐prepared LDH structurally and morphologically was characterized by scanning electron microscopy, X‐ray diffraction, and Fourier transform IR. Electrochemical studies revealed that Ni−Al−HCF film modified glassy carbon (GC) electrode exhibited remarkable electrocatalytic activity toward the oxidation of paracetamol. The electrochemical behavior of PC on the Ni−Al−HCF film was investigated in detail. Under optimum experimental conditions, the electrocatalytic response of the modified GC electrode was linear in the PC concentration range 3×10−6−–1.5×10−3 mol L−1, with a detection limit of 8×10−7 mol L−1 (S/N=3), using hydrodynamic amperometry. In addition, the modified electrode exhibited good reproducibility, long‐term stability and anti‐interference property. The fabricated sensor was successfully applied to determination of PC in various pharmaceutical preparations such as tablets, oral solution, and oral drops. Finally, the method was validated by the analysis of paracetamol spiked human serum samples, and good recoveries were obtained in the range of 99.2–103 %.

On the textural and crystalline properties of Fe-carbon xerogels. Application as Fenton-like catalysts in the oxidation of paracetamol by H2O2

A series of five Fe-carbon xerogels has been prepared by a sol-gel modified method of polymerization of resorcinol and formaldehyde, iron being incorporated in the form of ferrous acetate. Some modifications, such as the monomer used, the use of a surfactant and the step of addition of the ferrous acetate have been done in order to study their influence on the textural and crystalline properties of the final solids obtained. Fe-carbon xerogels have been characterized by N2 adsorption, mercury porosimetry, thermal analysis, scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD) and inductively coupled plasma mass spectrometry (ICP-MS). All samples contain micropores, with the exception of that prepared in the presence of an anionic surfactant. However, they are mainly meso- and/or macropores samples, the ratio of mesopore to macropore volume depending on the synthesis conditions. The amounts of iron in the samples, as well as the crystalline phases formed are also different. Fe-carbon xerogels were tested as catalysts in the removal of paracetamol from aqueous solution by a combined process of adsorption and Fenton-like oxidation under mild conditions, 25 °C and pH nearly neutral. Values of oxidations of paracetamol between 78 and 95% were achieved after 5 h of reaction, and the 90% of paracetamol was removed after only 37 min with two of the catalysts. The activity seems to be correlated with the high dispersion of small nanoparticles of iron, mainly present as zero-valent iron.

Voltammetric paracetamol sensor using a gold electrode made from a digital versatile disc chip and modified with a hybrid material consisting of carbon nanotubes and copper nanoparticles

A composite consisting of carbon nanotubes (CNT) and copper nanoparticles (CuNPs) was prepared by a chemical reduction method, and its structure characterized by scanning electron microscopy, transmission electron microscopy energy dispersive spectroscopy and FT-IR spectrometry. The hybrid composite was deposited on the surface of a disposable gold electrode that was manufactured from a commercial digital versatile gold disc by a drop casting method. The electrochemical properties of the modified electrode were investigated by cyclic voltammetry and differential pulse voltammetry. The sensor showed an excellent electrocatalytic activity towards oxidation of paracetamol (PA). The calibration plot (with current typically measured at 0.41 V vs. Ag/AgCl) is linear in the 0.5 to 80 μM concentration range, and the detection limit is as low as 10 nM. The sensor was successfully applied to the determination of PA in spiked water and tablet samples where it gave recoveries ranging between 95.25 and 100.5 %.

Kinetic study of oxidation of paracetamol by water-soluble colloidal MnO2 in the presence of an anionic surfactant

The kinetics of the oxidation of paracetamol [PCM] by water-soluble colloidal MnO2 was investigated spectrophotometrically at 298 K in the absence and presence of an anionic surfactant, sodium dodecyl sulphate (SDS), in aqueous solution. The reaction was first order with respect to [MnO2], [PCM] and [H2SO4]. The effects of [Mn(II)], [salt], dielectric constant and ionic strength of the medium on the kinetics of the reaction have also been examined. Micelles of SDS in aqueous solution accelerated the reaction rate, and partitioning of MnO2 in favour of the micellar pseudophase was remarkable. The catalytic effect of SDS in aqueous solutions has been treated by well-defined mathematical (Tuncay), Menger and Portnoy, and Piszkiewicz models. The binding constant (7.59 × 10−2 mol−1 dm3), dissociation constant (32.43), rate constant in the micellar phase (5.15 × 104 s−1), cooperativity index (1.98) and various thermodynamic activation parameters have been evaluated, and on the basis of the observed kinetic data, possible reaction mechanism and rate law have been proposed.

Synthesis of 5-[(2-hydroxynaphthalen-1-yl)diazenyl]isophthalic acid and its application to electrocatalytic oxidation and determination of adrenaline, paracetamol, and tryptophan

In this study, Au nanoparticles/poly 5-[(2-hydroxynaphthalen-1-yl)diazenyl] isophthalic acid film modified glassy carbon electrode (AuNPs/poly(NDI)/GCE) has shown excellent electrocatalytic activity toward the oxidation of adrenaline (ADR), paracetamol (PAC), and tryptophan (Trp). The bare glassy carbon electrode (GCE) fails to separate the oxidation peak potentials of these molecules, while the poly(NDI) film modified electrode can resolve them. Electrochemical impedance spectroscopy (EIS) indicates that the charge transfer resistance of the bare electrode decreases as 5-[(2-hydroxynaphthalen-1-yl)diazenyl] isophthalic acid is electropolymerized on the bare electrode. Furthermore, EIS exhibits enhancement of electron transfer kinetics between analytes and the electrode after electrodeposition of Au nanoparticles. Differential pulse voltammetry results show that the electrocatalytic current increases linearly in the ranges of 0.01–680.0μmolL−1 for ADR, 0.05–498.0μmolL−1 for PAC, and 3.0–632.0μmolL−1 for Trp; with detection limits (S/N=3) of 0.009μmolL−1, 0.005μmolL−1, and 0.09μmolL−1 for ADR, PAC, and Trp, respectively. The proposed method has been successfully applied for simultaneous determination of ADR, PAC, and Trp in biological samples.

Study of the paracetamol degradation pathway that generates color and turbidity in oxidized wastewaters by photo-Fenton technology

Abstract This study aims determining the effect that certain kind of water contaminants have on the changes of turbidity during their oxidation. Phenol is considered by its frequent presence in industrial discharges; meanwhile paracetamol is representative of emerging pollutants of pharmaceutical origin. Quite different results are observed in the turbidity changes during the oxidation of both pollutants that evolve following the kinetics of a reaction intermediate. The analysis of paracetamol and phenol degradation pathways reveals that operating conditions are important in the formation of intermediates that cause turbidity. The maximum turbidity levels are achieved operating at the ratios 12 mol HO per 100 mg contaminant. However the turbidity generated during the paracetamol oxidation only reaches a third of the intensity achieved with phenol. During the paracetamol degradation, the intermediates causing turbidity are similar to the ones found during the phenol decomposition. These species are generated during the initial minutes of oxidation and possess structures of large size and molecular weight. At the maximum turbidity point, muconic acid and hydroquinone are identified and found to coexist with other compounds such as pyrogallol and resorcinol. Therefore, the path involving metasubstitution would be the main originator of turbidity. It is noteworthy the rapid formation of muconic acid that coexists with resorcinol-like species. These compounds enable the establishment of hydrogen bond interactions that yield supramolecular structures.

Microwave Irradiation‐Assisted Exfoliation of Boron Nitride Nanosheets: A Platform for Loading High Density of Nanoparticles

AbstractBoron nitride nanosheets (BNNS) were first time successfully exfoliated from hexagonal boron nitride (h‐BN) in an ethanol‐sodium hydroxide media using a microwave irradiation method. This simple and low‐cost exfoliation method enabled the fast produce of high quality BNNS within 2 min. The average sheet thickness and lateral size of BNNS were 4.34 nm and 1.13 μm, respectively. The exfoliated BNNS bear a strong negative charge and was demonstrated to be an excellent platform for depositing high density nanoparticles after proper surface modification. As an example, unique core‐shell nanostructure of BNNS/dense palladium nanoparticles was synthesized and its electrochemical catalytic behaviour towards the oxidation of paracetamol was studied in detail.

Ferricyanide confined into the integrative system of pyrrolic surfactant and SWCNTs: The enhanced electrochemial sensing of paracetamol

An enhanced paracetamol sensor was developed based on the integrative system of single walled carbon nanotubes (SWCNTs) and the pyrrolic surfactant, (11-pyrrolyl-1-yl-undecyl)triethylammonium tetrafluoroborate (A2), in which confined the redox probe, Fe(CN)63−/4−. A well-defined redox peaks of the firmly confined Fe(CN)63−/4− with dramatically negative shift in the half-wave potential compared to Fe(CN)63−/4− in aqueous solution was observed at GCE/polyA2-Fe(CN)63−/4−/SWCNTs. To understand the unusual Fe(CN)63−/4− partitioning in this microheterogeneous system, the responses of the Fe(CN)63−/4− at the electrodes modified by SWCNTs, polyA2, SWCNTs/polyA2, and polyA2/SWCNTs were investigated, respectively. The results of cyclic voltammetry (CV) and differential pulse voltammetry (DPV) indicated that the proposed electrode exhibiting efficient electrocatalytic capability towards the paracetamol oxidation. Thereafter, an amperometric assay for paracetamol at GCE/polyA2-Fe(CN)63−/4−/SWCNTs was developed at 0.4V with an enhanced linear range from 3.4×10−7∼7.98×10−4M.

ChemInform Abstract: Electro‐Oxidation of Paracetamol in the Presence of Malononitrile: Application for Green, Efficient, None‐Catalyst, Simple and One‐Pot Electro‐Synthesis of New Paracetamols.

Abstract Electrochemical oxidation of paracetamol has been studied in the presence of malononitrile as a nucleophile in a phosphate buffer solution (0.15 mol/L, pH 7), using cyclic voltammetric techniques. The results indicated that the N -acetyl- p -benzoquinone-imine derived from paracetamol participates in a 1,4-Michael-type addition reaction with the malononitrile to form the corresponding paracetamol derivatives ( 6a , 7a ). The present study has led to the development of a simple, green, non-catalyst and one-pot electrochemical method with high atom economy under mild conditions.

Pharmaceutical Electrochemistry: the Electrochemical Oxidation of Paracetamol and Its Voltammetric Sensing in Biological Samples Based on Screen Printed Graphene Electrodes

Pharmaceutical Electrochemistry: the Electrochemical Oxidation of Paracetamol and Its Voltammetric Sensing in Biological Samples Based on Screen Printed Graphene Electrodes