Potentiometric Determination Research Articles

Biogenic Functionalized ZnO/CuO Nanocomposite Sensor for Potentiometric Determination of Pseudoephedrine-HCl in Pure and Commercial Products

لقد ولدت الإمكانيات الوظيفية الفائقة لأكاسيد الزنك (ZnO) والنحاس (CuO) النانوية اهتمامًا كبيرًا باستخدام أكاسيد المعادن مثل المركبات النانوية المميزة والنشطة كهربائيًا في الدراسات المتعلقة بالقياسات الجهدية والمتحسسات. تم تحضير هذه الأكاسيد النانوية من مستخلص بذور شجرة الليوسينا (Leucaena leucocephala) كطريقة صديقة للبيئة. إذ تم اقتراح تطوير متحسس غشائي من أسلاك النحاس المطلية بمركب نانوي ZnO/CuO كطريقة جديدة للتقدير الجهدي لهيدروكلوريد السيدوإيفيدرين (PSD) في أشكاله النقية وجرعاتها الصيدلانية. بوجود كلوريد البولي فينيل (PVC) كبوليمر ذو وزن جزيئي عالي و"أورثو- نيتروفينيل أوكتيل إيثر (o-NPOE) كوسيط مذيب، تم دمج PSD مع حمض الفوسفوتونجستيك (PTA) لإنتاج هيدروكلوريد السيدوإيفيدرين- فوسفوتونجستات ( PSD-PT) كأساس للتحسس. أظهر المتحسس المحور حساسية وانتقائية عالية جدًا لتقدير وقياس PSD بعلاقة خطية تبلغ 1.0×10-8 -1.0 ×10-2 مول لتر-1. وأظهرت معادلة الخط المستقيم (معادلة الإنحدار) EmV = (-58.143) log [PSD] + 526.71. وباستخدام المتحسس المقترح، يمكن تقديرهيدروكلوريد السيدوإيفيدرين بشكل فعال في أشكاله النقية والمنتجات والتجارية.

Utilization of azamacrocyclic ionophores as recognition elements for the potentiometric determination of gallic acid in various matrices

Gallic acid is a naturally occurring low molecular weight triphenolic molecule identified as a potent antioxidant, protecting against various types of reactive species and non-radicals. Three novel carbon paste electrodes were developed for the potentiometric determination of gallic acid. Azamacrocyclic ionophors; cyclen, hexacyclen, and kryptofix-22 were utilized as recognition ionophores separately. A multi-walled carbon nanotubes/titanium oxide nanocomposite was employed as the ion-to-electron transducer in the designed sensors. The prepared transducer was characterized by FT-IR and TEM. Molecular docking was implemented to study the recognition mechanism between these ionophores and the gallic acid molecule. It revealed promising binding interactions between gallic acid and the three recognition ionophores, especially hexacyclen and Kryptofix-22. In studying the potentiometric response of the proposed sensors, they exhibited high stability, sensitivity, accuracy, and precision in the quantitation of gallic acid. Gallic acid can be accurately quantified over the linearity range of 1 × 10−1–1 × 10−3 M, 1 × 10−2–1 × 10−6 M, and 1 × 10−2–1 × 10−6 M with a Limit of detection (LOD) 4 × 10−4 M, 3 × 10−7 M, and 7 × 10−7 M, for CPE1, CPE 2 and CPE 3, respectively. The electrodes showed high efficiency in determining gallic acid in Krameria lappacea root alcoholic extract, black tea, green tea, and human plasma without sophisticated pretreatment steps.

A cutting edge potentiometric determination of baricitinib in synthetic wastewater and in tablet dosage form using modified carbon paste ion-selective membrane

After the recent hit of COVID-19, many drugs were successively administered to save patients’ lives and those drugs reached aquatic sources, one of those drugs was Baricitinib. Driven by the current situation, a potentiometric technique using an ion-selective membrane (ISM) recipe drop cast on a modified carbon paste electrode was optimized for the superior determination of Baricitinib (BAR). The molecular docking was customized to optimize the proper ionophores incorporated in the ISM, revealing that beta-cyclodextrin (β-CD) is the most compatible ionophore with the studied drug. A multivariate optimization experimental design was employed to optimize the best experimental condition for the analytical method. To this end; dual nanoparticles (multi-walled carbon nanotubes and copper oxide nanoparticles) were incorporated in the carbon paste electrode, and the ISM recipe was enriched with β-CD and cation-exchanger (phosphotungstic acid) in a polyvinylchloride matrix plasticized with dibutyl phthalate. A Nernstian slope equal to 19.97 mV/decade with a linearity range of 7.99 × 10−7–1.00 × 10−3 M was obtained. The validated sensor exhibited good recovery when used to determine the studied drug in synthetic wastewater and tablet dosage form. The greenness of the method was evaluated using the Complementary Green Analytical Procedure Index and Blue Applicability Grade Index.

Simple, rapid and enzyme-free assay for potentiometric determination of L-cysteine based on meso-2,3-dimercaptosuccinic acid self-assembled gold electrode

As a sulfur containing α-amino acid in nature, L-cysteine plays a crucial role in a variety of metabolic pathways with many important physiological functions. However, it is still a great challenge to construct a simple and rapid approach for L-cysteine up to now. In this paper, a simple, rapid and enzyme-free method was developed for potentiometric determination of L-cysteine by using meso-2,3-dimercaptosuccinic acid self-assembled monolayer on gold electrode. The surface morphology and property of self-assembled membrane with and without L-cysteine combined were characterized by means of scanning electron microscopy, X-ray photoelectron spectroscopy, electrochemical impedance spectroscopy, and cyclic voltammetry, respectively. The recognition mechanism may be attributed to formation of hydrogen bonds between meso-2,3-dimercaptosuccinic acid and the target molecule of L-cysteine, producing a double electric layer at the sensing interface, that the membrane potential decreases with increasing concentration of L-cysteine. The assay results showed that good linear potential response to L-cysteine in Tris-HCl buffer solution (pH=7.0) was obtained in a range of 1.0 × 10-8 to 1.0 × 10-3 mol/L, with a slope of −57.00 ± 0.63 mV/-pc (25 °C) and a detection limit of 7.9 × 10-9 mol/L. The electrode possessed fast response time (45 s), good reproducibility, and strong anti-interference performance. Moreover, the electrode can be well applied to the detection of L-cysteine in pig serums with a recovery rate of 94.3 ∼ 106.3%, indicating a promising application prospect.

Review of potentiometric determination of cationic surfactants

Abstract Cationic surfactants (CSs) are surface-active compounds containing a positively charged polar group and at least one alkyl chain as a nonpolar group. Due to their structure, they tend to adsorb on negatively charged surfaces and interact with biopolyanions. It leads to their wide use as disinfectants, cleaning agents, fabric softeners, hair care products, emulsifiers, corrosion inhibitors, etc. Considering their extensive use and also their toxicity, fast, simple, and accurate CSs determination is crucial in industrial process control, product quality assurance, and environmental monitoring. Potentiometric sensors meet all these requirements, so they stand as the primary method for CSs determination. In this review, numerous potentiometric methods for CSs determination have been described, with a particular focus on methods published in the period from 2000 to 2024. Due to their simplicity and good analytical performance, solid-state electrodes are the most commonly used type of sensor for CSs determination.

Highly selective and sensitive potentiometric determination of favipiravir in COVID-19 antiviral drug formulations

In this study, a novel all-solid-state electrochemical sensor based on favipiravir-tetraphenylborate (FAV-TPB) electroactive material was developed and reported for FAV’s highly selective and sensitive potentiometric determination in COVID-19 antiviral drug formulations. All-solid-state FAV selective sensor was fabricated by mixing and properly pressing FAV-TPB, graphite (G), multi-walled carbon nanotube (MWCNT), and paraffin oil (PO). In order to obtain the best sensor response, the sensor component ratios were optimized. The most satisfying response characteristics was obtained with the sensor composition FAV-TPB:G:MWCNT:PO in the ratio 32.5:42.5:5:20 (w/w %). The developed sensor displayed a wide linear near-Nernstian response to FAV over the concentration of 1.0 × 10−6 − 1.0 × 10−1 molL−1 with a slope of 53.6 ± 1.4 mV (R2 = 0.9997). The detection limits of the sensor was calculated as 6.0 × 10−7 molL−1, respectively. The dynamic response time of the sensor was 7 s, and the sensor exhibited fairly reproducible potentiometric responses. In the pH range of 6.0–8.0, the sensor’s potential response was not affected by the pH change of the test solutions. The improved sensor had a wide temperature tolerance, and its response remained unchanged in the 10–40 ℃ temperature range. The interference effect of some chemical and biological species was evaluated by the matched potential method and separate solution method. The sensor worked stable for 12 weeks without any considerable change in its potential response. The analytical applications of the sensor were successfully carried out with the potentiometric titration of FAV with sodium tetraphenylborate solution and also the direct determination of favipiravir in COVID-19 antiviral drug formulations.

Potentiometric determination of nitrazepam in pharmaceutical dosage form and spiked plasma using a novel modified carbon paste electrode

AbstractA newly prepared solid contact ion selective electrode based on polyvinyl chloride membrane has been optimized and developed for determining nitrazepam in its pure form and synthetically prepared tablet dosage form. The proposed electrode was fabricated based on zeolite modified carbon paste electrode as a solid contact acting as a support for the membrane of PVC containing the ion complex of nitrazepam‐tetraphenyl borate as an electroactive material, and the plasticizer dibutyl phthalate. By improving the composition, the potentiometric properties were further enhanced, and the sensor achieved a Nernstian slope of 60.89 mV dec−1. The sensor was effective for detecting nitrazepam in the concentration range of 1.0×10−7 to 1.0×10−2 M, with a detection limit of 4.7×10−8 M. The sensor demonstrated excellent reversibility and reproducibility with a fast response time and application over a wide pH range. The developed electrode showed no significant effect when tested with various interfering species. It is successfully applied for accurate determination of nitrazepam in pure form, synthetically prepared tablet and spiked human plasma. The developed technique was validated and demonstrated high accuracy and precision. When compared statistically with the official method, there were no significant differences observed.

Potentiometric determination of Pb2+ ions using hybrid assembly of zinc oxide@polyaniline nanocomposites

ABSTRACT Over the recent years, the detection and determination of level of pollutant in environment have become indispensable. This allows for the adoption of various methods to evade the pollution caused by these toxicant entities. This has enhanced the interest of researchers to develop sustainable sensors to determine the trace level concentration of harmful target species. Although the list of these pollutants is undoubtedly too long, toxic metal ions, like Pb2+ ions beyond certain limit, can severely endanger the whole ecosystem. Therefore, the present study is dedicated toward the development of Pb2+ ion-selective electrode based on the membrane of zinc oxide/polyaniline nanocomposites. Nanocomposite assembly was synthesized using in-situ chemical oxidative polymerization method and characterized using spectroscopic techniques, such as energy‐dispersive spectroscopy, field emission scanning electron microscopy, Fourier transform infrared spectroscopy, dynamic light scattering, etc. The proposed potentiometric sensor exhibits excellent selectivity toward Pb2+ ions with detection limit of 2.239 × 10−6 M, Nernstian slope of 23.31 ± 2.5 mV decade−1 and a wide linear concentration range of 1.0 × 10−5 M to 1.0 × 10−1 M. Moreover, the designed Pb2+ ion-selective electrode was successfully examined for its practical applicability in Pb2+−EDTA complexometric titration as well as potentiometric determination of concentration of Pb2+ ions in real-life samples.

Ion-Selective Electrodes in the Food Industry: Development Trends in the Potentiometric Determination of Ionic Pollutants

Ion-Selective Electrodes in the Food Industry: Development Trends in the Potentiometric Determination of Ionic Pollutants

A novel potentiometric screen-printed electrode based on crown ethers/nano manganese oxide/Nafion composite for trace level determination of copper ion in biological fluids.

Copper levels in biological fluids are associated with Wilson's, Alzheimer's, Menke's, and Parkinson's diseases, making them good biochemical markers for these diseases. This study introduces a miniaturized screen-printed electrode (SPE) for the potentiometric determination of copper(II) in some biological fluids. Manganese(III) oxide nanoparticles (Mn2O3-NPs), dispersed in Nafion, are drop-casted onto a graphite/PET substrate, serving as the ion-to-electron transducer material. The solid-contact material is then covered by a selective polyvinyl chloride (PVC) membrane incorporated with 18-crown-6 as a neutral ion carrier for the selective determination of copper(II) ions. The proposed electrode exhibits a Nernstian response with a slope of 30.2 ± 0.3mV/decade (R2 = 0.999) over the linear concentration range 5.2 × 10-9 - 6.2 × 10-3mol/l and a detection limit of 1.1 × 10-9mol/l (69.9ng/l). Short-term potential stability is evaluated using constant current chronopotentiometry (CP) and electrochemical impedance spectroscopy (EIS). A significant improvement in the electrode capacitance (91.5 μF) is displayed due to the use of Mn2O3-NPs as a solid contact. The presence of Nafion, with its high hydrophobicity properties, eliminates the formation of the thin water layer, facilitating the ion-to-electron transduction between the sensing membrane and the conducting substrate. Additionally, it enhances the adhesion of the polymeric sensing membrane to the solid-contact material, preventing membrane delamination and increasingthe electrode's lifespan. The high selectivity, sensitivity, and potential stability of the proposed miniaturized electrode suggests its use for the determination of copper(II) ions in human blood serum and milk samples. The results obtained agree fairly well with data obtained by flameless atomic absorption spectrometry.

New potentiometric sensor for total phenolic assay of plant extracts

Abstract In this study, a sensitive, fast, and inexpensive new potentiometric determination method based on the Folin–Ciocalteu reagent (FCR) is proposed to determine the total phenolic content in plant extracts. For this purpose, a potentiometric-based all-solid-state-contact polyvinyl chloride membrane sensor was developed. Gallic acid compound was used as the active component (ionophore) in the developed sensor and the potentiometric behavior of the sensor was characterized. The detection limit of the selective sensor to the FCR was determined as 0.022 mol L−1 and showed a linear potential change in the concentration range of 0.0039 to 0.5 mol L−1 and a fast response time of 40 to 45 s. The developed sensor was also applied to the plant extracts and the obtained measurement results were found to be in agreement with the spectrometer results in the literature.

The use of thiazole derivative molecules as sensor materials: Potentiometric determination of Cu(II) ions

AbstractIn this study, poly(vinyl chloride) (PVC)–membrane potentiometric sensors for the determination of copper(II) ions were prepared using 2‐acetamido‐4‐(2‐hydroxyphenyl)thiazole (L1), 2‐amino‐4‐(trifluoromethyl)thiazole‐5‐carboxylic acid (L2) and ethyl 2‐amino‐4,5,6,7‐tetrahydrobenzo[d]thiazole‐6‐carboxylate (L3) ionophores. It was determined that the potentiometric performance characteristics of the sensors prepared with L1 were superior to the others. Based on these properties, the optimum membrane composition was determined as 3.0% ionophore (L1), 64.0% bis(2–ethylhexyl)adipate (DEHA), 32.0% PVC and 1.0% potassium tetrakis (p–chlorophenyl) borate (KTpClPB). The newly developed sensor had a low detection limit of 6.74 × 10−7 mol L−1 over a wide concentration range of 1.0 × 10−1–1.0 × 10−6 mol L−1. Compared with different metal ions, the sensor showed good selectivity to copper(II) ions, had a repeatable, stable and fast response time. The copper(II)–selective sensor could work in a wide range without being affected by pH changes (5.0–9.0). It was used as indicator electrode for the potentiometric titration of copper(II) ions with ethylenediaminetetraacetic acid (EDTA), and successfully applied for the determination of copper(II) ions content in different water samples.

Exploiting of Green Synthesized Metal Oxide Nanoparticles in the Potentiometric Determination of Metformin Hydrochloride in Pharmaceutical Products.

The advanced and highly functional properties of Al2O3 and NiO nanoparticles promote the widespread use of metal oxides as remarkable electroactive materials for sensing and electrochemical applications. The proposed study describes a comparison of the sensitivity and selectivity of two modified wire membrane sensors enriched with Al2O3 and NiO nanoparticles with conventional wire membranes for the quantification of the antidiabetic drug metformin hydrochloride (MTF). The results show linear relationships of the enriched Al2O3 and NiO nanosensors over the concentration ranges 1.0 × 10-10-1.0 × 10-2 mol L-1 and 1.0 × 10-6-1.0 × 10-2 M for both the modified sensors and the conventional coated wire membrane sensors. The regression equations were EmV = (52.1 ± 0.5) log (MTF) + 729 for enriched nanometallic oxides, EmV = (57.04 ± 0.4) log (MTF) + 890.66, and EmV = (58.27 ± 0.7) log (MTF) + 843.27 with correlation coefficients of 0.9991, 0.9997, and 0.9998 for the aforementioned sensors, respectively. The proposed method was fully validated with respect to the recommendations of the International Union of Pure and Applied Chemistry (IUPAC). The newly functionalized sensors have been successfully used for the determination of MTF in its commercial products.

Fabrication of Ion selective PVC Membrane Sensor for Potentiometric Determination of Escitalopram Oxalate in its Pure Form and Pharmaceutical Tablet

Fabrication of Ion selective PVC Membrane Sensor for Potentiometric Determination of Escitalopram Oxalate in its Pure Form and Pharmaceutical Tablet

Potentiometric determination of terbinafine hydrochloride antifungal drug in pharmaceutical and biological fluids using ion selective electrodes

Potentiometric determination of terbinafine hydrochloride antifungal drug in pharmaceutical and biological fluids using ion selective electrodes

Disposable Screen-Printed Microchip Based on Nanoparticles Sensitive Membrane for Potentiometric Determination of Lead

Realization of screen-printed disposable microchip based on organic membrane sensitive layer highly responsive to lead has been demonstrated for the first time. Fabrication, potentiometric characterization and analytical application of the novel microchip have been reported. A sensitive layer comprises TiO2 nanoparticles and multiwalled carbon nanotubes “MWCNTs” composite incorporated in PVC membrane has uploaded on the plastic screen-printed microelectrode substrate surface using novel protocol. The new chip provided a linear behavior for Pb2+ ions over the lead concentration range of 1 × 10−6–1 × 10−1 mole L−1 with super Nernstian sensitivity (49 mV), relatively long life span (>4 months), and a fast response time (10 s). The advantages showed by the microchip include simple fabrication, small size, mass production, cost effectiveness, and automation and integration feasibility. The realized new microchip has been successfully utilized in the quantification of some lead (II) samples with average recovery of 101.9% and the RDS was <3.

Validation and Application of Screen-Printed Microchip for Potentiometric Determination of Metformin Hydrochloride in Tablet Dosage Form.

Metformin is an oral biguanides hypoglycaemic agent, which used to lower the blood glucose levels in people with type 2 diabetes mellitus. Many analytical techniques have been used to quantify the drug in different pharmaceutical dosage forms; however, most of these methods have limited throughput in the quality control application. A disposable potentiometric microsensor responsive to metformin has recently been reported. For the first time, herein, this method of analysis has been validated according to IUPAC recommendations and successfully applied in the determination of metformin drug in some dosage form. Different drug formulations of metformin hydrochloride have been collected from the local pharmaceutical stores in Saudi Arabia and analysed using the validated microchip-based method of analysis. Subsequently, the results of this study showed that the validated method was linear, specific, precise, and accurate. The linear range was 1 × 10-1-1 × 10-5 mol L-1 and the correlation coefficient was 0.999. The limit of detection was 2.89 × 10-6 mol L-1, and the limit of quantification was 8.77 × 10-6 mol L-1. This method demonstrated high precision, with an RSD% of less than 2.22%. The accuracy of this method was obtained by comparing the recovery percentage with percentage values less than 5%. The results obtained showed that there was no significant difference between the references, label, and recovery of less than 5%.

Synthesis, characterization and sensor properties of a new sulfonyl hydrazone derivative molecule: potentiometric determination of Pb(II) ions

Synthesis, characterization and sensor properties of a new sulfonyl hydrazone derivative molecule: potentiometric determination of Pb(II) ions

Coated Coated Wire, Coated Graphite and modified carbon paste Electrodes for Potentiometric Determination of Azithromycin

Coated Coated Wire, Coated Graphite and modified carbon paste Electrodes for Potentiometric Determination of Azithromycin

CCQM-K173.1 - Assay of sodium carbonate. Final report

Main textThe CCQM key comparison CCQM-K173.1 is a subsequent comparison to CCQM-K173. It was performed to demonstrate the capability of KRISS to measure the amount content of bases. The institutes could use a method of their choice, although the use of coulometry or titrimetry with potentiometric determination of the endpoint was expected. The result of SMU was used as a link to the original comparison CCQM-K173.The results of KRISS were in good agreement with the reference value and may serve as evidence to support respective CMC claims.To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).