Supramolecular Atropine Potentiometric Sensor

A supramolecular atropine sensor was developed, using cucurbit[6]uril as the recognition element. The solid-contact electrode is based on a polymeric membrane incorporating cucurbit[6]uril (CB[6]) as an ionophore, 2-nitrophenyl octyl ether as a solvent mediator, and potassium tetrakis (4-chlorophenyl) borate as an additive. In a MES-NaOH buffer at pH 6, the performance of the atropine sensor is characterized by a slope of (58.7 ± 0.6) mV/dec with a practical detection limit of (6.30 ± 1.62) × 10−7 mol/L and a lower limit of the linear range of (1.52 ± 0.64) × 10−6 mol/L. Selectivity coefficients were determined for different ions and excipients. The obtained results were bolstered by the docking and spectroscopic studies which demonstrated the interaction between atropine and CB[6]. The accuracy of the potentiometric analysis of atropine content in certified reference material was evaluated by the t-Student test. The herein proposed sensor answers the need for reliable methods providing better management of this hospital drug shelf-life while reducing its flush and remediation costs.

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The Long-Lasting Story of One Sensor Development: From Novel Ionophore Design toward the Sensor Selectivity Modeling and Lifetime Improvement

Sensors ◽

10.3390/s21041401 ◽

2021 ◽

Vol 21 (4) ◽

pp. 1401

Author(s):

Larisa Lvova ◽

Donato Monti ◽

Corrado Di Natale ◽

Roberto Paolesse

Keyword(s):

Anion Exchanger ◽

Specific Interaction ◽

Spectroscopic Studies ◽

Polymeric Membranes ◽

Polymeric Membrane ◽

Active Components ◽

Nitrite Ion ◽

Working Mechanism ◽

Axial Coordination ◽

Porphyrin Aggregation

The metalloporphyrin ligand bearing incorporated anion-exchanger fragment, 5-[4-(3-trimethylammonium)propyloxyphenyl]-10,15,20-triphenylporphyrinate of Co(II) chloride, CoTPP-N, has been tested as anion-selective ionophore in PVC-based solvent polymeric membrane sensors. A plausible sensor working mechanism includes the axial coordination of the target anion on ionophore metal center followed by the formed complex aggregation with the second ionophore molecule through positively charged anion-exchanger fragment. The UV-visible spectroscopic studies in solution have revealed that the analyte concentration increase induces the J-type porphyrin aggregation. Polymeric membranes doped with CoTPP-N showed close to the theoretical Nernstian response toward nitrite ion, preferably coordinated by the ionophore, and were dependent on the presence of additional membrane-active components (lipophilic ionic sites and ionophore) in the membrane phase. The resulting selectivity was a subject of specific interaction and/or steric factors. Moreover, it was demonstrated theoretically and confirmed experimentally that the selection of a proper ratio of ionophore and anionic additive can optimize the sensor selectivity and lifetime.

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Potentiometric Carboxylate Sensors Based on Carbazole-Derived Acyclic and Macrocyclic Ionophores

Chemosensors ◽

10.3390/chemosensors9010004 ◽

2020 ◽

Vol 9 (1) ◽

pp. 4

Author(s):

Ville Yrjänä ◽

Indrek Saar ◽

Mihkel Ilisson ◽

Sandip A. Kadam ◽

Ivo Leito ◽

...

Keyword(s):

Detection Limit ◽

Vinyl Chloride ◽

Anion Exchanger ◽

Linear Range ◽

Ph Sensitivity ◽

Ion Selective Electrodes ◽

Solid Contact ◽

Response Characteristics ◽

Potentiometric Response ◽

Poly Vinyl Chloride

Solid-contact ion-selective electrodes with carbazole-derived ionophores were prepared. They were characterized as acetate sensors, but can be used to determine a number of carboxylates. The potentiometric response characteristics (slope, detection limit, selectivity, and pH sensitivity) of sensors prepared with different membrane compositions (ionophore, ionophore concentration, anion exchanger concentration, and plasticizer) were evaluated. The results show that for the macrocyclic ionophores, a larger cavity provided better selectivity. The sensors exhibited modest selectivity for acetate but good selectivity for benzoate. The carbazole-derived ionophores effectively decreased the interference from lipophilic anions, such as bromide, nitrate, iodide, and thiocyanate. The selectivity, detection limit, and linear range were improved by choosing a suitable plasticizer and by reducing the ionophore and anion exchanger concentrations. The influence of the electrode body’s material upon the composition of the plasticized poly(vinyl chloride) membrane, and thus also upon the sensor characteristics, was also studied. The choice of materials for the electrode body significantly affected the characteristics of the sensors.

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Detection limit of polymeric membrane potentiometric ion sensors: how can we go down to trace levels?

Analytica Chimica Acta ◽

10.1016/s0003-2670(99)00396-7 ◽

1999 ◽

Vol 397 (1-3) ◽

pp. 103-111 ◽

Cited By ~ 34

Author(s):

Yanming Mi ◽

Sally Mathison ◽

Roderick Goines ◽

Alicia Logue ◽

Eric Bakker

Keyword(s):

Detection Limit ◽

Polymeric Membrane ◽

Ion Sensors ◽

Potentiometric Ion Sensors

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Nanomolar Detection of Alkyl Dimethyl Hydroxyethyl Ammonium Surfactant by a Lipophile-doped Solid Contact Electrode

Journal of Environmental Analytical Chemistry ◽

10.4172/2380-2391.1000101 ◽

2014 ◽

Vol 01 (01) ◽

Author(s):

Hazem M Abu Shawish ◽

M Gaber ◽

Abdalla M Khedr ◽

Khalid I Abed-Almonem

Keyword(s):

Solid Contact ◽

Nanomolar Detection ◽

Contact Electrode

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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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