Screen-printed Microsensors Using Polyoctyl-thiophene (POT) Conducting Polymer As Solid Transducer for Ultratrace Determination of Azides

Two novel all-solid-state potentiometric sensors for the determination of azide ion are prepared and described here for the first time. The sensors are based on the use of iron II-phthalocyanine (Fe-PC) neutral carrier complex and nitron-azide ion-pair complex (Nit-N3−) as active recognition selective receptors, tetradodecylammonium tetrakis(4-chlorophenyl) borate (ETH 500) as lipophilic cationic additives and poly(octylthiophene) (POT) as the solid contact material on carbon screen-printed devices made from a ceramic substrate. The solid-contact material (POT) is placed on a carbon substrate (2 mm diameter) by drop-casting, followed, after drying, by coating with a plasticized PVC membrane containing the recognition sensing complexes. Over the pH range 6-9, the sensors display fast (< 10 s), linear potentiometric response for 1.0 × 10−2–1.0 × 10−7 M azide with low detection limit of 1.0 × 10−7 and 7.7 × 10−8 M (i.e., 6.2–4.8 ng/ml) for Fe-PC/POT/and Nit-N3−/POT based sensors, respectively. The high potential stability and sensitivity of the proposed sensors are confirmed by electrochemical impedance spectroscopy (EIS) and constant-current chronopotentiometry measurement techniques. Strong membrane adhesion and absence of delamination of the membrane, due to possible formation of a water film between the recognition membranes and the electron conductor are also verified. The proposed sensors are successfully applied for azide quantification in synthetic primer mixture samples. Advantages offered by these sensors are the robustness, ease of fabrication, simple operation, stable potential response, high selectivity, good sensitivity and low cost.

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All Solid-State Poly (Vinyl Chloride) Membrane Potentiometric Sensor Integrated with Nano-Beads Imprinted Polymers for Sensitive and Rapid Detection of Bispyribac Herbicide as Organic Pollutant

Molecules ◽

10.3390/molecules24040712 ◽

2019 ◽

Vol 24 (4) ◽

pp. 712 ◽

Cited By ~ 13

Author(s):

Nashwa Abdalla ◽

Maha Youssef ◽

H. Algarni ◽

Nasser Awwad ◽

Ayman Kamel

Keyword(s):

Solid State ◽

Electrochemical Impedance ◽

Organic Pollutant ◽

Solid Substrate ◽

Hplc Method ◽

Potentiometric Sensors ◽

Pvc Membrane ◽

Aliquat 336 ◽

Solid Contact ◽

Selective Membrane

All-solid-state potentiometric sensors were prepared by using polyaniline (PANI) as the solid contact material. A film of PANI (thickness approximately being 0.25 µm) was deposited on a solid substrate (carbon screen printed platform). The PANI layer was subsequently coated with an ion-selective membrane (ISM) containing uniform-sized molecularly imprinted nanoparticles to produce a solid-contact ion-selective electrode (SC/ISE) for bispyribac herbicide (sensor I). In addition, aliquat 336 was also used as an ion exchanger in plasticized PVC membrane (sensor II). The proposed sensors revealed a remarkably improved sensitivity towards bispyribac ions with anionic slopes of −47.8 ± 1.1 (r2 = 0.9995) and −44.4 ± 1.4 (r2 = 0.9997) mV/decade over a linear range 1.0 × 10−2–8.6 × 10−6 M, 1.0 × 10−2–9.0 × 10−6 M and detection limits of 1.33 and 1.81 µg/mL for sensors I and II, respectively.Selectivity of both sensors is significantly high for different common pesticides and inorganic anions. The potential stability of the SC/ISEs was studied using chronopotentiometry. Electrochemical impedance spectrometry was used to understand the charge-transfer mechanisms of the different types of ion-selective electrodes studied. The impedance response of the electrodes was modelled by using equivalent electrical circuits. The sensors were used for a direct measurement of the bispyribac content in commercial herbicide formulations and soil samples collected from agricultural lands planted with rice and sprayed with bispyribac herbicide. The results agree fairly well with data obtained using HPLC method.

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Arrays of solid contact potentiometric sensors for separate determination of some cephalosporin antibiotics

Industrial laboratory Diagnostics of materials ◽

10.26896/1028-6861-2021-87-5-5-13 ◽

2021 ◽

Vol 87 (5) ◽

pp. 5-13

Author(s):

E. G. Kulapina ◽

A. E. Dubasova ◽

O. I. Kulapina ◽

V. D. Ankina

Keyword(s):

Response Time ◽

Reference Model ◽

Complex Compounds ◽

Potentiometric Sensors ◽

Separate Determination ◽

Solid Contact ◽

Active Components ◽

Membrane Surfaces ◽

Cephalosporin Antibiotics

Arrays of potentiometric sensors including developed solid-contact unmodified and modified sensors based on tetradecylammonium associates with complex compounds of silver (1) and some β-lactam antibiotics (cefazoline, cefuroxime, cefotaxime (n = 3 – 6)) are proposed; polyaniline and copper oxide being modifiers. The main electroanalytic properties of the sensors are determined (the range of the determined concentrations in antibiotic solutions 1 × 10–4 – 0.1 M, 46.3 < S < 48, Cmin = n × 10–5 М, response time 4 – 10 sec, potential drift 4 – 6 mV/day, service life — 2 months). It is shown that modification of the membrane surfaces brings the steepness of the electrode functions to Nernst-values for single-charged ions of the antibiotics under study; reduces the response time and the detection limits, the linearity intervals of the electrode functions being the same. The potentiometric selectivity coefficients of unmodified and modified sensors based on different electrode active components (EAC) to the studied cephalosporins in the presence of interfering antibiotics are close to unity; cross sensitivity parameters for the considered sensors (the average slope of the electrode function of the sensor Sav, the unselectivity factor F, and the reproducibility factor K) are 46.3 < S (mV/pC) < 48; 0.85 < F < 0.90; 144 < K < 170, respectively. Application of sensors in the multisensory analysis of model mixtures of cephalosporin antibiotics is shown. Method of artificial neural networks (ANN) is used for processing of analytical signals. The correctness of the determination is carried out using «spike tests» on the reference model mixtures (the relative error of the determination does not exceed 12 %).

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DISPOSABLE SCREEN PRINTED POTENTIOMETRIC SENSORS FOR DETERMINATION OF FREE RADICALS

Sensors and Microsystems ◽

10.1142/9789812776457_0058 ◽

2002 ◽

Cited By ~ 1

Author(s):

L. CAMPANELLA ◽

G. FAVERO ◽

S. MARINO ◽

R. PILLOTON ◽

M. TOMASSETTI

Keyword(s):

Free Radicals ◽

Potentiometric Sensors ◽

Screen Printed

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Screen-Printed Sensor Based on Potentiometric Transduction for Free Bilirubin Detection as a Biomarker for Hyperbilirubinemia Diagnosis

Chemosensors ◽

10.3390/chemosensors8030086 ◽

2020 ◽

Vol 8 (3) ◽

pp. 86 ◽

Cited By ~ 2

Author(s):

Ayman H. Kamel ◽

Abd El-Galil E. Amr ◽

Hoda R. Galal ◽

Mohamed A. Al-Omar ◽

Abdulrahman A. Almehizia

Keyword(s):

Electrochemical Impedance ◽

Biological Fluids ◽

Ion Association ◽

High Specificity ◽

Cost Effective ◽

Pvc Membrane ◽

Phosphate Solution ◽

High Potential Stability ◽

Potential Stability ◽

Screen Printed

Novel reliable and cost-effective potentiometric screen-printed sensors for free bilirubin (BR) detection were presented. The sensors were fabricated using ordered mesoporous carbon (OMC) as an ion-to-electron transducer. The ion-association complex [Ni(bphen)3]2+[BR]2− was utilized as a sensory recognition material in the plasticized Polyvinyl Chloride (PVC) membrane. The membrane was drop-casted on the OMC layer, which is attached on a carbon conductor (2-mm diameter). In a 50 mM phosphate solution of pH 8.5, the electrodes offered a Nernstian slope of −26.8 ± 1.1 (r2 = 0.9997) mV/decade with a range of linearity 1.0 × 10−6–1 × 10−2 M towards free bilirubin with a detection limit 8.8 × 10−7 M (0.52 µg/mL). The presented sensors offered good features in terms of reliability, ease of design, high potential stability, high specificity and good accuracy and precision. Chronopotentiometric and electrochemical impedance spectrometric measurements were used for short-term potential stability and interfacial capacitance calculations. The sensors were used for the determination of free bilirubin in biological fluids. The data obtained are fairly well consistent with those obtained by the reference spectophotometric method. Based on the interaction of free BR with albumin (1:1), the sensors were also utilized for the assessment of albumin in human serum.

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Beryllium-Ion-Selective PEDOT Solid Contact Electrode Based on 9,10-Dinitrobenzo-9-Crown-3-Ether

Sensors ◽

10.3390/s20216375 ◽

2020 ◽

Vol 20 (21) ◽

pp. 6375

Author(s):

Junghwan Kim ◽

Dae Hee Kim ◽

Jin Cheol Yang ◽

Jae Sang Kim ◽

Ji Ha Lee ◽

...

Keyword(s):

Electrochemical Impedance ◽

Constant Current ◽

Solid Contact ◽

Response Characteristics ◽

Best Response ◽

Wide Ph Range ◽

Selective Membrane ◽

Nernstian Slope ◽

Ph Range ◽

Contact Electrode

A beryllium(II)-ion-selective poly(ethylenedioxythiophene) (PEDOT) solid contact electrode comprising 9,10-dinitrobenzo-9-crown-3-ether was successfully developed. The all-solid-state contact electrode, with an oxygen-containing cation-sensing membrane combined with an electropolymerized PEDOT layer, exhibited the best response characteristics. The performance of the constructed electrode was evaluated and optimized using potentiometry, conductance measurements, constant-current chronopotentiometry, and electrochemical impedance spectroscopy (EIS). Under optimized conditions, which were found for an ion-selective membrane (ISM) composition of 3% ionophore, 30% polyvinylchloride (PVC), 64% o-nitro phenyl octyl ether (o-NPOE), and 3% sodium tetraphenylborate (NaTPB), the fabricated electrode exhibited a good performance over a wide concentration range (10−2.5–10−7.0 M) and a wide pH range of 2.0–9.0, with a Nernstian slope of 29.5 mV/D for the beryllium (II) ion and a detection limit as low as 10−7.0 M. The developed electrode shows good selectivity for the beryllium(II) ion over alkali, alkaline earth, transition, and heavy metal ions.

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Cost-Effective Potentiometric Platforms Modified with Multi-Walled Carbon Nanotubes (MWCNTs) and Based on Imprinted Receptors for Fluvoxamine Assessment

Polymers ◽

10.3390/polym12030673 ◽

2020 ◽

Vol 12 (3) ◽

pp. 673

Author(s):

Heba M. Hashem ◽

Saad S. M. Hassan ◽

Ayman H. Kamel ◽

Abd El-Galil E. Amr ◽

E. M. AbdelBary

Keyword(s):

Carbon Nanotubes ◽

Electrochemical Impedance ◽

Biological Fluids ◽

Pharmaceutical Preparations ◽

Cost Effective ◽

Hplc Method ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes ◽

Screen Printed

A simple, efficient and reliable analytical method was developed and used for the determination of the fluvoxamine drug (FLV) in pharmaceutical preparations and biological fluids. The method is based on the cost-effective screen-printed platform for the potential transduction of the drug. Host-tailored molecular imprinting polymer (MIP) was integrated with the potentiometric platform as a recognition receptor, in which FLV, acrylamide (AAm), ethylene glycol dimethacrylate (EGDMA) and acetonitrile were used as a template, functional monomer, cross-linker, and solvent, respectively. MIP particles were dispersed in plasticized poly (vinyl chloride) (PVC) and the membrane was drop-casted on carbon screen-printed electrode. The MIP, in addition to non-imprinted polymers (NIP), was characterized and the binding experiment revealed high affinity and adsorption capacity of MIP towards FLV. The proposed sensor displayed near-Nernstian cationic slope of 55.0 ± 0.8 mV/decade (r2 = 0.999) with a low detection limit of 4.8 × 10−6 mol/L over a wide pH range (3.0–8.5). The electrochemical features of the proposed sensors including electrochemical impedance spectroscopy (EIS) and chronopotentiometry measurements (CP) in the presence of multi-walled carbon nanotubes (MWCNTs) as a solid contact transducer were also investigated. The applications of the proposed sensor for the determination of FLV in different dosage forms with recovery values (98.8%–101.9%) and (97.4%–101.1%), respectively compared with the reference HPLC method with acceptedFandt-student tests values at the 95% confidence level.

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Novel Solid-State Potentiometric Sensors Using Polyaniline (PANI) as A Solid-Contact Transducer for Flucarbazone Herbicide Assessment

Polymers ◽

10.3390/polym11111796 ◽

2019 ◽

Vol 11 (11) ◽

pp. 1796 ◽

Cited By ~ 2

Author(s):

Kamel ◽

Amr ◽

Abdalla ◽

El-Naggar ◽

Al-Omar ◽

...

Keyword(s):

Electrochemical Impedance ◽

Potentiometric Sensors ◽

Carbon Substrate ◽

Pani Film ◽

Solid Contact ◽

Ion Sensing ◽

Glassy Carbon Substrate ◽

Contact Transducer ◽

Charged Carrier ◽

Liquid Chromatographic

Novel potentiometric solid-contact ion-selective electrodes (SC/ISEs) based on molecularly imprinted polymers (MIPs) as sensory carriers (MIP/PANI/ISE) were prepared and characterized as potentiometric sensors for flucarbazone herbicide anion. However, aliquat S 336 was also studied as a charged carrier in the fabrication of Aliquat/PANI/ISEs for flucarbazone monitoring. The polyaniline (PANI) film was inserted between the ion-sensing membrane (ISM) and the electronic conductor glassy carbon substrate (GC). The sensors showed a noticeable response towards flucarbazone anions with slopes of −45.5 ± 1.3 (r2 = 0.9998) and −56.3 ± 1.5 (r2 = 0.9977) mV/decade over the range of 10−2–10−5, 10−2–10−4 M and detection limits of 5.8 × 10−6 and 8.5 × 10−6 M for MIP/PANI/ISE and Aliguat/PANI/ISE, respectively. The selectivity and long-term potential stability of all presented ISEs were investigated. The short-term potential and electrode capacitances were studied and evaluated using chronopotentiometry and electrochemical impedance spectrometry (EIS). The proposed ISEs were introduced for the direct measurement of flucarbazone herbicide in different soil samples sprayed with flucarbazone herbicide. The results agree well with the results obtained using the standard liquid chromatographic method (HPLC).

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