Oxidation Of Pyrrole Research Articles

Conducting polypyrrole and polypyrrole/manganese dioxide composites prepared with a solid sacrificial oxidant of pyrrole

Polypyrrole was prepared by the oxidation of pyrrole with solid manganese dioxide. The present study concerns the chemistry of this process rather than materials properties of the products. The oxidant alone is insoluble in aqueous medium but the reductive dissolution takes place in the presence of pyrrole. Polypyrrole is the exclusive product below the stoichiometric mole ratio [MnO2]/[pyrrole] = 1.25, and polypyrrole/manganese dioxide composites result at higher ratios. Unlike with iron(III) chloride where protons are generated during the oxidation of pyrrole, with manganese dioxide they are consumed and water is a by-product. The sufficient acidity of the reaction medium is thus needed in order to obtain conducting materials. The presence of organic dyes in the preparation of polypyrrole improved the conductivity. One-dimensional morphology of polypyrrole was observed when methyl orange was introduced to the reaction mixture.

Electrochemical investigation of different electrodes toward the removal of non-basic nitrogen compound from model diesel fuel

• Electrochemical denitrification of non-basic nitrogen compound in model diesel fuel. • Electrooxidative investigation of pyrrole in divided cell using several electrodes. • Electrooxidation and electropolymerization as two dominated proposed mechanism. • Carbon-based electrodes have better tendency towards oxidation than polymerization. • CP electrode could attain highest denitrification and current efficiency. In this study, the electrochemical removal of pyrrole as a non-basic nitrogen compound in diesel model fuel was investigated using platinum (Pt), graphite (Gr), carbon paper (CP), lead/lead dioxide (Pb/PbO 2 ), and tin/tin dioxide (Sn/SnO 2 ) working electrodes in a divided cell. Electrochemical analysis such as cyclic voltammetry, linear sweep voltammetry, electrochemical impedance spectrometry, and Tafel test was utilized to determine different behavior of electrodes. According to gas chromatography results, pyrrole removal efficiency at a constant current density of 17 mA cm −2 during 6 h was in the range of 83%–100% for Sn/SnO 2 and CP electrodes, respectively. The denitrification reaction using CP, Gr, and Sn/SnO2 electrodes was diffusion-controlled regarding data extracted from cyclic voltammetry at various scan rates. However, the adsorption mechanism was dominated by Pt and Pb/PbO 2 electrodes. Tafel analysis demonstrated that the electrocatalytic activity of electrodes is as follows: Pt > CP > Gr > Pb/PbO 2 > Sn/SnO 2 . Besides, the formation of polypyrrole and low oxygen evolution potential diminished Pt pyrrole removal efficiency. Carbon-based electrodes with pyrrole oxidation potential near Pt electrode and higher oxygen evolution potential can be utilized as efficient and cost-effective electrodes in the denitrification process.

A shock tube and modeling study on the auto-ignition properties of pyrrole in O2/CO2 atmosphere at elevated pressures

Understanding the details of pyrrole combustion chemistry in the O2/CO2 atmosphere contributes to developing the strategies for nitrogen oxides (NOx) control during the pressurized oxy-coal combustion (POCC). However, the existing kinetic models for pyrrole oxidation lack multi-dimensional validation, and the ignition delay times (IDTs) of pyrrole in the O2/CO2 atmosphere are still scarce. This study measured the IDTs of pyrrole in O2/CO2 atmospheres at an elevated pressure of 5.2 bar, temperatures from 1271 to 1645 K, and equivalence ratios Φ = 0.5, 1.0, and 2.0 in a shock tube. The results demonstrate that the pyrrole IDTs decrease with decreasing equivalence ratio and the pyrrole mixtures in O2/CO2 atmospheres have longer IDTs than those in O2/Ar atmospheres. A pyrrole oxidation kinetic model (HUST pyrrole model) has been developed by updating 19 reactions in our previous model (HUST pyridine model). HUST pyrrole model gives a satisfactory prediction of the IDTs of pyrrole in the O2/Ar atmosphere (measured by MacNamara et al.) and O2/CO2 atmosphere (measured in this study) and the profiles of pyrrole, HCN, and NO (measured by Yamamoto et al.). The comparison of the HUST pyrrole model with the Lumbreras model (2001) was conducted by the pyrrole IDTs and profiles of HCN using the sensitivity and flux analysis. The addition of HNCPROP and modification of R665 (C3H3 + O2 = CH2CO + HCO), R1273 (AC3H4CN + H2 => ALLYLCN + H), R1251 (PYRLNE = ALLYLCN), R1238 (PYRROLE + H = PYRLYL + H2), and R1240 (PYRROLE + OH = PYRLYL + H2O) in HUST pyrrole model significantly improve the prediction performance for the pyrrole oxidation. The effects of the equivalence ratio and CO2 on the IDTs for pyrrole oxidation have been analyzed.

Electrically Conductive and 3D-Printable Oxidized Alginate-Gelatin Polypyrrole:PSS Hydrogels for Tissue Engineering.

Electroactive hydrogels can be used to influence cell response and maturation by electrical stimulation. However, hydrogel formulations which are 3D printable, electroactive, cytocompatible, and allow cell adhesion, remain a challenge in the design of such stimuli-responsive biomaterials for tissue engineering. Here, a combination of pyrrole with a high gelatin-content oxidized alginate-gelatin (ADA-GEL) hydrogel is reported, offering 3D-printability of hydrogel precursors to prepare cytocompatible and electrically conductive hydrogel scaffolds. By oxidation of pyrrole, electroactive polypyrrole:polystyrenesulfonate (PPy:PSS) is synthesized inside the ADA-GEL matrix. The hydrogels are assessed regarding their electrical/mechanical properties, 3D-printability, and cytocompatibility. It is possible to prepare open-porous scaffolds via bioplotting which are electrically conductive and have a higher cell seeding efficiency in scaffold depth in comparison to flat 2D hydrogels, which is confirmed via multiphoton fluorescence microscopy. The formation of an interpenetrating polypyrrole matrix in the hydrogel matrix increases the conductivity and stiffness of the hydrogels, maintaining the capacity of the gels to promote cell adhesion and proliferation. The results demonstrate that a 3D-printable ADA-GEL can be rendered conductive (ADA-GEL-PPy:PSS), and that such hydrogel formulations have promise for cell therapies, in vitro cell culture, and electrical-stimulation assisted tissue engineering.

Conducting and Magnetic Composites Polypyrrole Nanotubes/Magnetite Nanoparticles: Application in Magnetorheology

The study aims at the design of nanostructured hybrid materials that are both conducting and magnetic. Conducting polypyrrole nanotubes were prepared by the oxidation of pyrrole with iron(III) chlo...

One-Pot Preparation of Conducting Melamine/Polypyrrole/Magnetite Ferrosponge

Polypyrrole was deposited in situ on the macroporous open-cell melamine sponge by the oxidation of pyrrole with iron(III) chloride. The oxidant was used in excess, and the reaction mixture after th...

Electrochemical oxidation of pyrrole on the surface of the amorphous alloy of Al87Ni8Y5 composition in the 0.5 M sulfate acid solution

Polypyrrole films were deposited on the surface both of the outer and contact sides of the Al 87 Ni 8 Y 5 amorphous alloy electrodes by potentiodynamic oxidation of 0.25 M pyrrole in 0.5 M H 2 SO 4 aqueous solution. It is determined that already in the first anode cycle of potential scanning a nanofilm of polypyrrole is formed on Al 87 Ni 8 Y 5 amorphous alloy electrodes. The further pyrrole oxidation in potentiodynamic mode occurs easily and film of polypyrrole actively formed on the surface of the working electrode. Cyclic voltammogramms has been analyzed and the process of electrochemical oxidation of pyrrole and redox transformations of polypyrrole at these electrodes is described. It is shown that the difference in film topology is due to the surface topology of electrodes, which determines stability of surface oxide films on these surfaces. Studies of the electrode surface topology and also morphology, structure and composition of polypyrrole films produced on an amorphous alloy electrode were carried out using Fourier-transform infrared spectroscopy with attenuated total reflection (FTIR-ATR), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). It has been confirmed using FTIR analysis that the films deposited on the surface of the Al 87 Ni 8 Y 5 electrodes corespond to polypyrrole which are in the form of hydrosulfate salt. The analysis of the received electron microscopy images shown that a polypyrrole films produced both on the contact and outer sides of the working electrodes has developed surface topology, which depends on surface quality and nature of amorphizing additive in electrode alloy. The peculiarity of pyrrole oxidation and redox transformations of deposited polypyrrole on the Al 87 Ni 8 Y 5 electrode is mainly due to the high concentration of pyrrole in the solution and to a lesser extent to the properties of the electrode surfaces and naturally formed oxide films. Electrochemical oxidation of pyrrole on the Al 87 Ni 8 Y5 electrode in the potentiodynamic mode accompanied by the formation of quasi-spherical nanoaggregates, which form a dense primary film of polypyrrole. The formed nanoaggregates in the following cycles of potential scanning act as peculiar polymer electrodes. Keywords: pyrrole, amorpfous alloys, electrochemical oxidation, polypirrole, structure.

The evolution of the molecular structure of polypyrrole during chemical polymerization

It was found that different molecular structures can be formed during chemical oxidation of aniline depending on various factors. These factors might change during the process of the reaction, leading to various reaction products. In this work, inspired by polyaniline, the chemical oxidation of pyrrole was analysed in order to find or disprove the existence of any dependence of the molecular structure of the pyrrole oxidation products on the stage of the reaction and describe the kinetics of the chemical oxidation of pyrrole. The polymerization proceeding was followed using various characterization techniques such as pH, temperature changes and open circuit potential. UV–Vis and surface-enhanced Raman spectra were measured at different time intervals. Results reveal the initiation of branching of the polypyrrole chain and the time dependence of overoxidation.

Heterogeneous and platinum-initiated homogeneous combustion of nitrogen-containing heterocyclic compounds in the argon and water vapor media at elevated pressure

The paper presents the results on the oxidation of pyrrole and pyridine in the argon and water vapor media at high pressure and uniform heating of the tubular stainless steel reactor to 823 K. Experiments were carried out with lean and stoichiometric mixtures (fuel equivalence ratio φ = 0.78–1.01) at their dilution level x D = 36–65% mol. Based on the time dependences of the reaction mixture temperature, it is revealed that oxidation proceeds via the mechanisms of homogeneous and heterogeneous reactions. It was found that the oxidation rate of pyrrole depends on the amount of corrosion products accumulated on the reactor wall. It is shown that a Pt-Rh/Pt thermocouple inserted into the center of the reaction volume intensifies pyridine oxidation in the near-surface region. The difference in the oxidation mechanisms of pyrrole and pyridine is explained by the structure of their molecules.

The influence of the oxidant on structural and morphological properties of conductive polypyrrole

Polypyrrole was synthesized using chemical oxidation of monomer Pyrrole with ferric chloride as an oxidant. Series of reactions were carried out to accomplish different oxidant to monomer ratio. The synthesized black powders were characterized using different techniques like SEM, FTIR, and XRD. The bulk conductivity of the samples was measured using two probe conductivity measurement system. The conductivity of these samples at room temperature was ranging from 545.19 μS/cm to 215.78 μS/cm, as the oxidant to monomer ratio varied from 0.5 to 3. The morphology observed in SEM of these samples shows the different sizes of the globular particle of Polypyrrole. All the characteristic absorption bands of Polypyrrole were observed in the FTIR spectrum obtained from synthesized samples. A little shift in band position is observed because of various oxidants to the monomer ratio. The broad peak is observed between 20 and 30°in the XRD pattern, indicating the amorphous nature of Polypyrrole.

Polypyrrole/gelatin cryogel as a precursor for a macroporous conducting polymer

Soft macroporous conducting polypyrrole/gelatin cryogels were prepared by a single-step oxidation of pyrrole in the frozen aqueous solution of gelatin. Corresponding aerogels were obtained after freeze-drying of cryogels. Polypyrrole component was collected after removing gelatin by acid hydrolysis. Such polypyrrole has unique macroporous morphology with pore walls composed of two-dimensional sheets. Its mechanical integrity proved the connectivity of the conducting phase in cryogels. Macroporous free-standing polypyrrole obtained after hydrolytic removal of gelatin had conductivity and specific surface area one order of magnitude higher than both the precursor aerogel and the reference polypyrrole prepared by cryotechnique in the absence of gelatin.

Ab initio kinetic mechanism of OH-initiated atmospheric oxidation of pyrrole

The comprehensive kinetic mechanism of the OH-initiated gas-phase oxidation of pyrrole is first theoretically reported in a broad range of conditions (T = 200–2000 K &P = 1–7600 Torr). On the potential energy surface constructed at the M06–2X/aug-cc-pVTZ level, the temperature- and pressure-dependent behaviors of the title reaction were characterized using the stochastic Rice–Ramsperger–Kassel–Marcus based Master Equation (RRKM-ME) rate model. The corrections of the hindered internal rotation and quantum tunneling treatments were included. The calculated results reveal the competition between the two distinct pathways: OH-addition and direct H-abstraction. The former channels are found favorable at low-temperature and high-pressure range (e.g., T < 900 K and P = 760 Torr) where non-Arrhenius and positive pressure-dependent behaviors of the rate constants are noticeably observed, while the latter predominate at temperatures higher than 900 K at atmospheric pressure and no pressure dependence on the rate constant is found. The predicted global rate constants are in excellent agreement with laboratory values; thus, the derived kinetic parameters are recommended for modeling/simulation of N-heterocycle-related applications in atmospheric and even in combustion conditions. Besides, pyrrole should not be considered as a persistent organic pollutant owing to its short atmospheric lifetime (∼1 h) towards OH radicals. The secondary mechanisms of the subsequent reactions of two OH-pyrrole adducts (namely, I1 and I2) with two abundant species, O2/NO, which are relevant to the atmospheric degradation process, were also investigated. It is also revealed by TD-DFT calculations that two OH-pyrrole adducts (I1 &I2), nine intermediates, Ii (i = 3–11) and four products (P1, P2, P3 and P6) can undergo photodissociation under the sunlight.

Methyl red dye in the tuning of polypyrrole conductivity

Polypyrrole was prepared by the oxidation of pyrrole with iron(III) chloride in aqueous medium in the presence of methyl red dye. While the acid form of dye had no effect on the polypyrrole synthesis, the presence of its sodium salt increased the conductivity from 1–5 S cm−1 up to 84 S cm−1 for the polymerizations carried out with variable dye concentration at 20 °C. When the reaction temperature was reduced to −50 °C, the conductivity increased up to 104 S cm−1. At temperatures below −20 °C, the polymerization took place in frozen reaction medium, in ice. The morphology of polypyrrole was mainly globular and often converted to particles of irregular size and shape. It was concluded that one-dimensional morphology, nanotubes or nanofibers characteristic of polypyrrole, is not an automatic prerequisite for the high conductivity of this polymer.

Oxidized Multiwalled Carbon Nanotubes (ox-MWCNTs) As an Oxidation Agent for Pyrrole (PY) Polymerization: MWCNT@Polypy Composite Formation

Composites of conducting polymers and carbon nanomaterials has attracted great attention both in fundamental and applied research. They exhibits high conductivity, large specific surface area, and excellent mechanical properties. These systems can be fabricated either by simple mixing of carbon material and conducting polymer or by in-situ oxidative polymerization of monomer in the presence of carbon nanostructures. Polypyrrole has been deposited on the SWCNTs or MWCNTs by chemical or electrochemical oxidation of monomer in solution containing carbon nanotubes. In the case of chemical polymerization, Fe(III) ions or are used as an oxidation agents. For the formation of MWCNT@polyPY composite, oxidized MWCNTs were used for pyrrole oxidation and polymerization process initiation.MWCNTs were oxidized in solution containing hydrogen peroxide 30 wt% , sulphuric acid 96 wt%, and a mixture of H2SO4 96 wt% and H2O2 30 wt% in ratio 70:30. The oxidized MWCNTs were characterized with FTIR and Ramat spectroscopy, XPS, and thermogravimetric analysis. Nature of the functional groups and the presence of structural defects on the nanotube surface were determined. The MWCNTs oxidized in sulphuric acid and hydrogen peroxide mixture, containing ca. 5% of carboxylate groups were used as an oxidation agent for pyrrole polymerization. The composite was formed in toluene solution containing pyrrole and ox-MWCNTs. Polymer was deposited at the MWCNTs surface and the MWCNT@polyPY composite is formed (inset in Figure 1). The thickness of the polymeric layer coating the carbon nanotube surface (in range from 10 to 100 nm) can be controlled by the time of polypyrrole deposition, concentration of pyrrole in solution, and the stirring conditions.The electrochemical properties of MWCNT@polyPY composites in different solutions were also investigated. The effects of the supporting electrolyte nature and the solvent were examined. Figure 1 shows the voltammetric behavior of MWCNT@polyPY thin layer deposited at the surface of gold electrode by drop coating method recorded in water containing NaClO4. Voltammogram exhibits two large oxidation peaks. The second one at ca. 0.4 V corresponds to the process of polypyrrole oxidation. The rate of oxidation process of polypyrrole that is deposited at the MWCNTs surface (MWCNT@polyPY) is much higher in comparison the oxidation of pristine polymer formed under conventional chemical conditions. Also, an efficiency of the polymer phase oxidation significantly increases in the case of composite. The nature of the large surface peak at ca. 0 V (Figure 1) is still under investigation.Composite MWCNT@polyPY material can be used as an electroactive material in charge storage devices due to its capacitance properties and the fast rate of charge transfer. Figure 1

Synthesis of Polypyrrole/V2O5 Composite Film on the Surface of Magnesium Using a Mild Vapor Phase Polymerization (VPP) Method for Corrosion Resistance

The vapor phase polymerization (VPP) method is a conventional strategy for synthesizing conducting polymers (CPs) on the surfaces of various materials. However, the current VPP method performed on a metal surface usually requires harsh reaction conditions, such as high temperature and low vacuum. In this paper, a polypyrrole (PPy) and vanadium pentoxide (V2O5) composite film was synthesized on the surface of Mg using a mild VPP method. Here, V2O5 was used as an oxidant, and it was found that the oxidation of pyrrole (Py) vapor on the surface of V2O5, which had been previously coated on the surface of Mg, could be performed at room temperature under normal atmospheric pressure. The formation of the PPy/V2O5 composite was verified by Fourier transform infrared spectroscopy (FTIR) and energy dispersive X-ray (EDX) spectroscopy. A thermogravimetric analyzer (TGA) was used to study the thermal stability of the composite. Subsequent corrosion tests showed that the PPy/V2O5 composite film could slow down the corrosion of Mg in 3.5 wt% NaCl. It is expected that the mild VPP method may find great potential in the fields of synthesis of CPs and the corrosion protection of reactive metals.

Azo dye aggregates and their roles in the morphology and conductivity of polypyrrole

Polypyrrole (PPy) synthesized by the oxidation of pyrrole with iron(III) chloride in the presence of sulfonic azo dyes exhibits fascinating nanometer-scale morphology and high conductivity, which are distinctly different from their counterparts prepared without dyes. The present work systematically studied the roles of sulfonic azo dye aggregates formed in acidic medium during the growth of PPy based on structural and elemental analysis. The formation of PPy nanostructures have been investigated by following the pH profile, by adjusting the precipitation rate of dye aggregates and by comparing the molecular structure of three azo dyes, viz. methyl orange, ethyl orange and Orange I. The results showed that the ethyl orange derived aggregates formed in iron(III) chloride solution and in hydrochloric acid solution had exactly the same structure as well as elemental composition. Aggregates derived from methyl orange formed in iron(III) chloride solution involved a trace amount of iron element. Orange I, another azo dye that can induce aggregates rapidly in iron(III) chloride solution, contributed negligibly to both the morphology and conductivity of PPy. The structure-directing effects of methyl orange/iron(III) complexes in directing PPy nanostructures seems to be unique and cannot be simply extended to other azo dyes, probably due to the dye interaction with iron ions.

ПОТЕНЦІОДИНАМІЧНЕ ОСАДЖЕННЯ ПОЛІПІРОЛУ НА ПОВЕРХНІ АМОРФНОГО СПЛАВУ СКЛАДУ Al87Ni8Y5

Polypyrrole films were deposited on the surface both of the outer and contact sides of the Al87Ni8Y5 amorphous alloy electrodes by potentiodynamic oxidation of 0.1 M pyrrole in 0.5 M H2SO4 aqueous solution. It was found that the oxidation of pyrrole on Al87Ni8Y5 amorphous alloy electrodes occurs comparatively easy and already during the first cycle of potential scanning a nanofilm of polypyrrole is formed. The formation of polypyrrole film essentially accelerates during following cycles of potential scanning. Cyclic voltammogramms has been analyzed and the process of electrochemical oxidation of pyrrole and redox transformations of polypyrrole at these electrodes is described. It is shown that the difference in film topology is due to the surface topology of electrodes, which determines stability of surface oxide films on these surfaces. Studies of the electrode surface topology and also morphology, structure and composition of polypyrrole films produced on an amorphous alloy electrode were carried out using Fourier-transform infrared spectro¬sco¬py with attenuated total reflection (FTIR-ATR), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). It has been confirmed using FTIR analysis that the films deposited on the surface of the Al87Ni8Y5 electrodes corespond to polypyrrole which are in the form of hydrosulfate salt. The analysis of the received electron microscopy images shown that polypyrrole films produced both on the contact and outer sides of the working electrodes has developed surface topology, which depends on surface quality and nature of amorphizing additive in electrode alloy. In addition, it is likely that a significant number of aggregates of polypyrrole macromolecules are formed in the solution, which further play the role of electrodes, where the oxidation of the corresponding monomer from its aqueous solution takes place. The results of EDX microanalysis shown presence in the polymeric films of small amount of metal impurities (in the form of sulfates mainly), which formed in the result of the corrosion of working electrode.

Corrosion Protection of AISI 1010 Using Doped MoS2 Conductive Polymers

In this study, Corrosion resistance of the coatings obtained by electrochemical oxidation of pyrrole and aniline on the mild steel has been investigated in 0.1 M hydrochloric acid medium. It was aimed to increase the resistance of the coatings to corrosion by adding MoS2 to the coating solutions while covering the Polypyrrole (PPy) and polyaniline (PANI). PPy, PAN, MoS2 doped PPy and MoS2 doped PANI coatings on the electrodes produced from mild steel were obtained by the Cyclic Voltammetry method in 0,1 M H2C2O4 environment. The voltamograms were carried out at a scan rate 100 V / s from 0.0 V to 1.0 V with 15 scans. The corrosion resistance of the coatings in 0.1 M HCl medium was determined by Tafel Polarization method. Best results were determined in MoS2 doped PPy coatings. Later, PPy coatings, MoS2 added PAN coatings and PANI coatings were determined respectively. The addition of MoS2 to the coating solution increased the corrosion resistance in both coatings. Similar results were obtained in different environments in our previous studies. It is understood that MoS2 additive makes the coating surface impermeable and prevents deformation in the coating.

Surfactants and amino acids in the control of nanotubular morphology of polypyrrole and their effect on the conductivity

Polypyrrole nanotubes were prepared by the oxidation of pyrrole in aqueous solutions of methyl orange and in the presence of 1–5 wt% of surface-active additives, surfactants, or amino acids. Three types of additives – anionic, non-ionic, and cationic – have been tested in the control of polypyrrole morphology and conductivity. The morphology of nanotubes was little dependent on surfactant type but the changes in size and aspect ratios were more pronounced with amino acids. Except for anionic surfactant, bis(2-ethylhexyl) sulfosuccinate, which behaved indifferently, all additives reduced the conductivity of polypyrrole, some even by four orders of magnitude. Based on FTIR spectroscopy, it is proposed that the hydrophobic interactions and/or hydrogen bonding between the additives and growing polypyrrole chains play the important role in reducing chain ordering, while the ionic interactions have limited effect.

A new molecularly imprinted polymer for selective extraction and pre-concentration of guaifenesin in different samples: Adsorption studies and kinetic modeling.

This paper describes the synthesis of a molecularly imprinted polymer by chemical oxidation of pyrrole as the functional monomer, and at the presence of guaifenesin as the template. The prepared polymer was used as adsorbent in molecularly imprinted solid-phase extraction followed by spectrophotometric determination. Different parameters in the solid-phase extraction including sample pH, adsorbent weight, washing solution, and elution solvent were studied to determine optimum conditions for isolation and enrichment of guaifenesin. The results showed guaifenesin was quantitatively adsorbed on the molecularly imprinted polymer at pH 6.0 and completely eluted with an ethanol-water solution (50% v/v). An enrichment factor of four with satisfactory recoveries (87.0-95.0%) was obtained. The solid-phase extraction columns could be used for up to six consecutive elution-loading cycles without significant decreases in the analyte recoveries. The method had a dynamic range of 3.0×10-6 -1.5×10-4 mol/L with a limit of detection and limit of quantification of 1.4×10-6 and 4.5×10-6 mol/L, respectively. The proposed procedure was used for the extraction and determination of guaifenesin in different pharmaceutical formulations, with satisfying results being achieved.