PVC Matrix Membrane Research Articles

Studies in synthesis of nano-zinc oxide mixed PVC matrix membrane and its application for ibuprofen drug removal

The present study performed pharmaceutical drug such Ibuprofen (IBP) separation by novel nano-Zinc oxide (ZnO) mixed PVC matrix membrane. The study represents an attempt to the synergistic effect of zinc oxide nanoparticle due to its catalytic nature and versatile PVC as polymeric membrane material to fabricate desired membrane for improving IBP removal considering hazardous environmental impacts of ibuprofen on aquatic as well as human life. The ZnO nanoparticles produced by novel sono-chemical precipitation method were confirmed by HRTEM analysis. The nano-ZnO mixed PVC membrane was prepared by phase inversion method using water as the non-solvent, N-Methyl-2-pyrrolidone (NMP) as the solvent and polyethylene glycol (PEG) 6 kDa as the pore forming agent. Membrane properties such as water uptake and contact angle, resistance estimation was also measured. The characterization Techniques such as FTIR, FESEM, FESEM-EDX were used to characterize zinc oxide and blended membranes to examine structural and functional groups. The effects of pH and transmembrane pressure and IBP concentration on IBP removal were taken into account to optimize membrane performance.1% nano-Zinc oxide mixed PVC membrane showed better flux recovery ratio 89%, IBP removal of about 67% among other modified membrane.

José Luís Fontes da Costa Lima – An example to be followed

I am very sad to communicate the death of the Emeritus Professor José Luís Fontes da Costa Lima, a leading chemist who made significant contributions to the development of Analytical Chemistry in Brazil. He graduated in Chemistry at the Faculty of Sciences of the University of Porto, in 1970. After that, he spent 9 years at the service of Portugal in Africa. In 1985, he concluded the doctoral program in Chemistry, specialty Analytical Chemistry, being approved with distinction and praise. At the beginning of his scientific career, Prof. Costa Lima experienced important moments when, together with colleagues from Barcelona, proposed a flow-through sandwich PVC matrix membrane electrode for flow injection analysis and, in collaboration with renowned scientists from Wales, UK, proposed an ion-selective electrode without an inner reference solution.

Studies in Synthesis of Nano-Zinc Oxide Mixed Pvc Matrix Membrane and its Application for Ibuprofen Drug Removal

Studies in Synthesis of Nano-Zinc Oxide Mixed Pvc Matrix Membrane and its Application for Ibuprofen Drug Removal

WITHDRAWN: Determination of ampicillin in pharmaceutical preparations by molecularly imprinted polymer in PVC matrix membrane

This revision was grounded on creating four electrodes based on molecularly imprinted polymers (MIPs). Were Ampicillin sodium was used (AMP-Na) as the template, 1-vinyl imidazole (VIZ) and vinyl acetate (VA) as monomer, and N, N-methylene bis acrylamide (MBAA) as cross-linkers and benzoyl peroxide as the motivator, two MIPs were set. The same composition was used in the preparation of non-impressed polymers (NIPs), but without the template (Ampicillin sodium). For the preparation of membranes, Numerous plasticizers, such as tri-poly phosphate (TOP) and dactyl phthalate (DOP), were used in the PVC matrix. Slop, recognition limit, lifetime, and linearity variety of AMP- MIPs electrodes are the study’s characteristics. There’s no contact with the Amoxicillin sodium drug in the obtained results from selectivity measurements on inquisitive cations (K+, Ca + 2, Al + 3) and certain pharmaceutical additives such as methyl paraben, propyl paraben and tri sodium citrate. Electrodes preparation have presented decent response including testing of pharmaceutical analysis.

Design and Study of Electrochemical Sensors Based on Polymer Inclusion Membranes Containing Polyoxometalates

Polyoxometalates (POM) are a class of inorganic compounds with various structures and remarkable electrical, magnetic and optical properties. Ion-pair complexes formed with some organic cations have high lipophilicity and they can be used as ionophores for PVC matrix membranes with active recognition function. The present study describes the construction and characterization of selective membrane sensors based on electroactive material incorporated in PVC matrix. They have been employed for the determination of ranitidine and nizatidine by using their complexes with silicotungstic acid as ionophores. The composition of the membrane has been optimized. The linear response range for both sensors was between 10-1-10-5M with quantification limits of 2.83�10-6M for ranitidine and 3.43�10-6M for nizatidine, and a response time shorter than 50 seconds. The new electrodes have been used for the potentiometrical determination of ranitidine and nizatidine in pharmaceutical products.

Synthesis and characterization of dendritic polypyrrole silver nanocomposite and its application as a new urea biosensor

ABSTRACTPolypyrrole and its silver nanocomposite were electrochemically synthesized from aqueous solutions containing pyrrole, potassium chloride (KCl) (system A); pyrrole, KCl, and an anionic surfactant sodium dodecyl sulphate (NaDS) (system B); and pyrrole, silver nitrate, NaDS (system C). Compact and dendritic patterns were observed depending on experimental conditions. The aggregates were characterized by powder X‐ray diffraction, energy‐dispersive X‐ray spectroscopy, scanning electron microscopy, high resolution transmission electron microscopic (HRTEM), and thermal studies (TG/DTG). HRTEM studies indicate that the particle size of PPy‐Ag nanocomposite is ∼30 nm. TG studies revealed that systems B and C, have different thermal behavior. Potassium ion selective electrodes were constructed using systems A, B, and C. The electrode prepared with PPy‐Ag nanocomposite showed nernstian behavior with maximum slope of 57 mV. ion‐selective electrode was also constructed for this system based on nonactin‐impregnated PVC matrix membrane. Urease enzyme was immobilized at the surface of as made ion‐selective electrode to develop urea biosensor showing good detection limit. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45705.

Polymeric Membrane Sensors for the Selective Determination of Metoclopramide Hydrochloride and their Applications to Pharmaceutical Analysis

Metoclopramide (MCP) ion selective electrodes based on metoclopramide-phosphotungstic acid (MCP-PT) ion pair complex in PVC matrix membrane were constructed. The plasticizers used were tri-butyl phosphate (TBP), di-octyl phenyl phosphonate (DOPP), di-butyl phthalate (DBPH), di-octyl phthalate (DOP), di-butyl phosphate (DBP), bis 2-ethyl hexyl phosphate (BEHP). The sensors based on TBP, DOPP, DBPH and DOP display a fast, stable and linear response with slopes 59.9, 57.7, 57.4, 55.3 mV/decade respectively at pH ranged 2-6. The linear concentration range between 1.0×10-5 – 1.0×10-2 M with detection limit 3.0×10-6 and 4.0×10-6 M for electrodes using TBP, DOPP and DBPH while electrode using DOP shows a linear concentration range between 3.0×10-5 – 1.0×10-2 M and detection limit 6×10-6 M. The selectivity coefficient values were calculated for MCP with respect to different inorganic cations, sugars and amino acids using the MCP depending on TBP plasticizer which is also used for the determination of MCP in pure solutions and in pharmaceutical preparations by direct, standard addition methods and as an indicator electrode in potentiometric titration with phosphotungstic acid (PT) giving satisfactory results.
 Key words: Metoclopramide-HCl membrane sensors , Metoclopramide determination , pharmaceutical analysis , PVC membrane sensors

Mefenamic Acid Selective Membranes Sensor and Its Application to pharmaceutical Analysis

PVC membrane sensor for the selective determination of Mefenamic acid (MFA) was constructed. The sensor is based on ion association of MFA with Dodecaphospho molybdic acid (PMA) and Dodeca–Tungstophosphoric acid(PTA) as ion pairs. Nitro benzene (NB) and di-butyl phthalate (DBPH) were used as plasticizing agents in PVC matrix membranes. The specification of sensor based on PMA showed a linear response of a concentration range 1.0 × 10–2 –1.0 × 10–5 M, Nernstian slopes of 17.1-18.86 mV/ decade, detection limit of 7 × 10-5 -9.5 × 10 -7M, pH range 3 – 8 , with correlation coefficients lying between 0.9992 and 0.9976, respectively. By using the ionphore based on PTA gives a concentration range of 1.0 × 10–4 –1.0 × 10–5 M, Nernstian slope of 17.18-18.4 mV/ decade, limit of detection 8.0 × 10–6-9.3 × 10-5M,pH range 3 – 8 and correlation coefficients range between 0.9984 and 0.9891, respectively. The measurement interferences in the presence of Li+, Na+, Mg2+ Ca2+, Fe3+and Al3+ were studied using separate and match potential methods for selectivity coefficient determination. The method was applied for the determination of Mefenamic Acid in pharmaceutical preparations

Mefenamic Acid Selective Membranes Sensor and Its Application to pharmaceutical Analysis

PVC membrane sensor for the selective determination of Mefenamic acid (MFA) was constructed. The sensor is based on ion association of MFA with Dodecaphospho molybdic acid (PMA) and Dodeca–Tungstophosphoric acid(PTA) as ion pairs. Nitro benzene (NB) and di-butyl phthalate (DBPH) were used as plasticizing agents in PVC matrix membranes. The specification of sensor based on PMA showed a linear response of a concentration range 1.0 × 10–2 –1.0 × 10–5 M, Nernstian slopes of 17.1-18.86 mV/ decade, detection limit of 7 × 10-5 -9.5 × 10 -7M, pH range 3 – 8 , with correlation coefficients lying between 0.9992 and 0.9976, respectively. By using the ionphore based on PTA gives a concentration range of 1.0 × 10–4 –1.0 × 10–5 M, Nernstian slope of 17.18-18.4 mV/ decade, limit of detection 8.0 × 10–6-9.3 × 10-5M,pH range 3 – 8 and correlation coefficients range between 0.9984 and 0.9891, respectively. The measurement interferences in the presence of Li+, Na+, Mg2+ Ca2+, Fe3+and Al3+ were studied using separate and match potential methods for selectivity coefficient determination. The method was applied for the determination of Mefenamic Acid in pharmaceutical preparations

Structural and electrochemical studies of heterogeneous ion exchange membranes based on polyaniline-coated cation exchange resin particles

Polyaniline was deposited on polystyrene sulfonated divinyl benzene resin by varying polymerization time to fabricate heterogeneous PVC matrix membranes.

Preparation and evaluation of new uranyl imprinted polymer electrode sensor for uranyl ion based on uranyl–carboxybezotriazole complex in pvc matrix membrane

In this study a new uranyl selective electrochemical sensors were prepared by using uranyl ionic imprinted polymer (IIP). The IIP was prepared by thermal polymerization using acrylic acid as a monomer, ethylene glycol dimethacrylate (EGDMA) as a cross linking and a benzoyl peroxide (BPO) as an initiator. Uranyl–carboxybenzotriazol (UO2–CBT) complex was used as an active material on the prepared polymer. Several uranyl electrodes were constructed by using different masses of polyvinyl chloride (PVC) matrix. Electrode parameters including slopes, working concentrations, pH, and interferences were evaluated. The electrodes exhibit a Nernstian response with slopes of 23.6 and 28.1mV/decade for graphite uranyl electrode and liquid uranyl electrode, respectively, over a wide range of concentration from 3×10−6 to 6×10−2M and a detection limit of 1×10−6M. It can be used in the pH range of 4.3–10.5 with a response time of less than 60s. The effect of ions interferences (such as: Cr3+, La3+, Ba2+, Ca2+, Cu2+, Na+, and K+) on the electrode response were evaluated. The IIP and nonimprinted polymer (NIP) membranes were characterized by Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron microscopy (SEM). The binding capacity and equilibrium dissociation constant were determined by studying the binding isotherm. The concentrations of uranyl ion in the prepared synthetic solutions determined by the standard addition method and the results were satisfactory with errors less than 7%. Finally, the prepared graphite UO2-IIP sensor was tested to determine the uranyl ions concentrations in a real environmental water sample by standard addition method. The results were compared with those obtained by spectrophotometric method which showed a good agreement. The developed electrode was found to be fast, sensitive and reliable indicated its potential use in measuring the uranly ion concentration in the field.

Potentiometric Sensors for the Determination of Valdecoxib in Pharmaceutical Preparation

Valdecoxib (VALD) selective electrodes based on VALD-5,6-diamino-2-thiouracil hydrochloride (DTUH) (VALD-DTUH) ion pair in PVC matrix membrane were constructed. The plasticizers used were dibutylphthalate (DBP) (Electrode B) tri-n-butylphosphate (TBP) (electrode C), or dioctylphthalate (DOP) (electrode) A. The electrodes gave the linear range between 6.0×10−6-17.9×10−3, 2.5×10−5–8.3×10−3M, M and 2.5×10−6–2.0×10−2M respectively. The slopes for linear range ranged from 39.29 to 58.76mV/decade with correlation coefficients lying between 0.997, 0.989 and 0.999 respectively. The best detection limit was 1.50×10−6M for the electrode based on DOP. Selectivity coefficients of VALD related to a number of interfering cation and some organic compounds and excipients were studied using matched potential method (MPM(, and there were negligible interference caused by most of the investigated species. The pH and life time of the electrodes were also studied. The direct determination of VALD shows an average recovery of (100.08-100.61 and 99.75-101.00)% and a mean relative standard deviation of (2.70-0.61 and 2.39-0.56)% for sensor A and B respectively. The results obtained by determination of VALD in tablets using the proposed sensors which comparable favorably with those obtained by spectrophotometric method. Validation of the method shows the suitability of the electrodes for the determination of VALD in pharmaceutical formulation.

Potentiometric Sensors for the Determination of Valdecoxib in Pharmaceutical Preparation

Valdecoxib (VALD) selective electrodes based on VALD-5,6-diamino-2-thiouracil hydrochloride (DTUH) (VALD-DTUH) ion pair in PVC matrix membrane were constructed. The plasticizers used were dibutylphthalate (DBP) (Electrode B) tri-n-butylphosphate (TBP) (electrode C), or dioctylphthalate (DOP) (electrode) A. The electrodes gave the linear range between 6.0×10−6-17.9×10−3, 2.5×10−5–8.3×10−3M, M and 2.5×10−6–2.0×10−2M respectively. The slopes for linear range ranged from 39.29 to 58.76mV/decade with correlation coefficients lying between 0.997, 0.989 and 0.999 respectively. The best detection limit was 1.50×10−6M for the electrode based on DOP. Selectivity coefficients of VALD related to a number of interfering cation and some organic compounds and excipients were studied using matched potential method (MPM(, and there were negligible interference caused by most of the investigated species. The pH and life time of the electrodes were also studied. The direct determination of VALD shows an average recovery of (100.08-100.61 and 99.75-101.00)% and a mean relative standard deviation of (2.70-0.61 and 2.39-0.56)% for sensor A and B respectively. The results obtained by determination of VALD in tablets using the proposed sensors which comparable favorably with those obtained by spectrophotometric method. Validation of the method shows the suitability of the electrodes for the determination of VALD in pharmaceutical formulation.

Construction and Potentiometric Study of Chloramphenicol Selective Electrodes Based on a PVC Matrix Membrane

Chloramphenicol succinate selective electrodes were prepared based on a complex Chloramphenicol succinate -phosphomolybdate as an active material using the plasticizers di-octyl phthalate (DOPH), tri-butyl phosphate (TBP), o-nitro phenyl octyl ether (ONPOE) and di-butyl phthalate (DBPH) in a PVC matrix membrane. The properties of the prepared electrodes were studied, such as: slope, concentration range, detection limit, lifetime, pH effect and selectivity. The experimental results showed that the best electrode was based on DOPH and DBPH as plasticizers, displaying a linear range from 1.00x10 −4 M to 1.00x10 −1 M and 1.00x10 −1 M to 2.00x10 −4 with a Nernstian slope of 58.5 mV/decade and 53.9 mV/decade, correlation coefficient of 0.9999 and 0.9998, The detection limit was 5.5x10 −5 M and 8.0x10 −5 , the lifetime was around 40 and 25 days respectively. The proposed electrodes were successfully applied to the determination of in Chloramphenicol succinate a pharmaceutical preparation. Keyword: Chloramphenicol; Ion-selective electrode; Potentiometry; Pharmaceutical analysis.

New Potentiometric and Spectrophotometric Methods for the Determination of Dextromethorphan in Pharmaceutical Preparations

New, simple and convenient potentiometric and spectrophotometric methods are described for the determination of dextromethorphan hydrobromide (DXM) in pharmaceutical preparations. The potentiometric technique is based on developing a potentiometric sensor incorporating the dextromethorphan tetrakis(p-chlorophenyl)borate ion-pair complex as an electroactive species in a plasticized PVC matrix membrane with o-nitophenyl octyl ether or dioctyl phthalate. The sensor shows a rapid near Nernstian response of over 1 × 10(-5) - 1 × 10(-2) mol L(-1) dextromethorphan in the pH range of 3.0 - 9.0. The detection limit is 2 × 10(-6) mol L(-1) DXM and the response time is instantaneous (2 s). The proposed spectrophotometric technique involves the reaction of DXM with eriochrom black T (EBT) to form an ion-associate complex. Solvent extraction is used to improve the selectivity of the method. The optimal extraction and reaction conditions have been studied, and the analytical characteristics of the method have been obtained. Linearity is obeyed in the range of 7.37 - 73.7 × 10(-5) mol L(-1) DXM, and the detection limit of the method is 1.29 × 10(-5) mol L(-1). The relative standard deviation (RSD) and relative error for six replicate measurements of 3.685 × 10(-4) mol L(-1) are 0.672 and 0.855%, respectively. The interference effect of some excepients has also been tested. The drug contents in pharmaceutical preparations were successfully determined by the proposed methods by applying the standard-addition technique.

Liquid Selective Electrodes for Dextromethorphan Hydrobromide Based on a Molecularly Imprinted Polymer in PVC Matrix Membrane

Liquid Selective Electrodes for Dextromethorphan Hydrobromide Based on a Molecularly Imprinted Polymer in PVC Matrix Membrane

Synthesis and Potentiometric Study of Atenolol Selective Electrodes and Their Use in Determining Some Drugs

Atenolol ion selective electrodes were constructed. This construction was based on drug complex formation with phosphomolybdic acid as ionophor and plasticizer, Di-butylphthalate (DBPH), Tri-butylphosphate (TBP), O-nitrophenyloctylether (ONPOE) and Di-octyl phthalate (DOP) in PVC matrix membrane. The matrix membrane was formed by mixing an appropriate plasticizer and drug complex with poly(vinyl chloride) PVC. The properties of following electrodes were studied, concentration range, slope, detection limit, response time, life time, pH effect and selectivity. The results showed that membranes (At-PMA+DBPH) and (At-PMA+ONPOE) gave a linear range from 1× 10 −5 to 1× 10 −1 and 5× 10 −6 to 1× 10 −2 respectively, with slopes of (55.6 and 40.5) mV/decade, correlation coefficients are 0.9996 and 0.9984, the detection limit was (8.5× 10 −6 and 3.5× 10 −5 ) M, and the response time for 10 −3 M were (15 and 25) second respectively. The proposed electrodes were successfully applied to the determination of atenolol in a pharmaceutical preparation and gave a good accuracy.

BATCH AND FLOW INJECTION POTENTIOMETRIC MONITORING OF CEFTRIAXONE SODIUM IN PHARMACEUTICAL PREPARATIONS USING TWO NOVEL MEMBRANE SENSORS

Two novel potentiometric sensors are prepared, characterized and successfully used for static and continuous determination of ceftriaxone sodium (CRXN). Both sensors are based on the use of plasticized PVC matrix membranes incorporating tetradodecylmethyl ammoniu m bromide (TDMAB), ortridodecylmethyl ammonium chloride (TDMAC) ion -exchangers and used for quantitative determination of CRXN at concentration level down to29 µM using both sensors with a good accuracy. Both sensors offer the advantages of fast response, reasonable selectivity, elimination of drug pre-treatment or separation steps, low cost and possible interfacings with computerized and automated systems. The use of plasticized membrane electrodes were used for continuous monitoring of CRXN offers the ad vantages of simple design, ease of construction and possible applications to small volumes of drug solutions with little manipulation and without pre-treatment. Both detectors display a wide dynamic measurement range of the drug under continuous mode of op eration with a flow rate of 2.0 ml.min -1 and used for quantitative determination of CRXN. The developed sensors were utilized in static continuous modes successfully for the determination of CRXN in pure powders and in dosage forms. It is worth noting that the developed membrane electrodes exhibited good selectivity toward CRXN over other cephalosporins such as; cefradine, ceftazidime, cefadroxil, cefaclor and cefoperazone, as well as other additives found in the pharmaceutical preparations such as; glucose, fructose and maltose.

Determination of Sodium Dodecyl Sulfate in Toothpastes by a PVC Matrix Membrane Sensor

AbstractThe construction and characteristic performance of a new potentiometric PVC membrane sensor responsive for sodium dodecyl sulfate (SDS) are described. The sensor is based on the use of cetyltrimethylammonium‐tetraphenylborate (CTA‐TPB) ion‐pair complex as electroactive material in PVC matrix in presence of dioctyl phthalate as a solvent mediator. The sensor exhibits a rapid, stable and near‐Nernstian response for SDS over the concentration range of 5 × 10−3–5 × 10−6 mol dm−3 at 25 ± 2 °C and the pH range 4–8.5 with slope of 59.6 mV/decade change in SDS concentration. The lower detection limit is 5 × 10−6 mol dm−3 and the response time is 45 s. The determination of selectivity coefficients for different anions shows there is no interference except that of dodecyl benzene sulfonate (DBS−) ion which has a strong interference. The results obtained in the determination of SDS in toothpastes, using this sensor as an indicator electrode, were compared with those obtained from the spectrophotometric method using methylene blue as the reagent.

Novel creatine biosensors based on all solid-state contact ammonium-selective membrane electrodes

Novel creatine bienzymatic potentiometric biosensors were prepared by immobilizing urease and creatinase on all solid-state contact PVC-containing palmitic acid and carboxylated PVC matrix membrane ammonium-selective electrodes without inner reference solution. Potentiometric characteristics of biosensors were examined in physiological model solutions at different creatine concentrations. The linear working range and long-term sensitivity of the biosensors were also determined. The creatine biosensors prepared by using the carboxylated PVC membrane electrodes showed more effective performance than those of the PVC containing palmitic acid membrane electrodes. Creatine assay in serum samples was successfully carried out by using the standard addition method.