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Green analytical methods are important techniques that aim to reduce or eliminate the use of harmful chemicals and waste in various analyses. These methods, based on green chemistry principles, are environmentally friendly and reliable. Electrochemical techniques have an essential role in diverse analyses, and are presented as a superior alternative to existing analytical devices in terms of different parameters. In the present review, we have comprehensively covered electrochemistry‐based sensors that are developed using green chemistry principles and evaluated their performance characteristics and specific working conditions. We here included sensors developed based on potentiometry and voltammetry methodologies, and detailed their greenness potentials based on certain metrics. Considering the advantages provided by these environmentally friendly new generation sensors, it will be inevitable for researchers working in this field to direct their attention to sensors that can be produced with green approaches. [ABSTRACT FROM AUTHOR]

In this study, we synthesized a new thiosemicarbazone derivative molecule (5) that exhibits sensor properties. The characterization of the synthesized molecule was performed using spectroscopic methods such as 1H−, 13C–NMR, FT–IR and Q–TOF. PVC‐membrane ion‐selective sensors were prepared in which the synthesized molecule was used as an ionophore. Surface images of the prepared sensors were examined by scanning electron microscope (SEM) technique. The prepared sensors exhibited selectivity towards barium(II) ions. The developed barium(II)‐selective sensor had a low detection limit of 5.54×10−7 M in the concentration range of 1.0×10−1–1.0×10−6 M. The proposed barium(II)‐selective sensor had fast response time, good repeatability and stability, and can be manufactured with low cost. The sensor can detect barium(II) ions in various water samples with very high recoveries. [ABSTRACT FROM AUTHOR]

Background: Ionophores in the composition of potentiometric ion‐selective electrodes interact directly with the analyte ion and enable the determination of ionic species in various samples. Objectives: In this study, a novel ion‐selective electrode based on 5‐bromosalicylaldehyde thiosemicarbazone was developed for the selective determination of Cr3+ ions. Methods: The optimum electrode composition contained ionophore, poly (vinyl chloride) (PVC), bis (2‐ethylhexyl) sebacate (BEHS) and potassium tetrakis (p‐chlorophenyl) borate (KTpClPB) in ratios of 4.0: 61.0: 34.0: 1.0 (mg), respectively. Potential measurements were performed using a computer‐controlled multi‐channel potentiometric measurement system. Results: The developed Cr (III)‐selective electrode exhibited a low detection limit of 3.96 × 10−6 M over a wide concentration range of 1.0 × 10−5 – 1.0 × 10−1 M (R2: 0.9979). The electrode exhibited good selectivity towards Cr3+ ions among metal ions with different charges. The chromium (III)‐selective electrode, which exhibited highly reproducible results in three different concentration ranges, also had a very fast response time of 5 s. Conclusions: The developed Cr (III)‐selective electrode were successfully performed in various beverage samples. As a result, the proposed electrode can be an alternative to other analytical methods in the analysis of Cr3+ ions. [ABSTRACT FROM AUTHOR]

Ion-selective electrodes or sensors are preferred by researchers in the determination of various ions since they provide very high selectivity and wide concentration range in environmental, industrial, clinical, agricultural, medicinal and routine laboratory analyses. Cadmium, a toxic heavy metal, poses a significant risk to humans and animals due to its wide use in the industry. Today, many analytical methods have been proposed for the determination of cadmium ions in various samples and their working conditions have been determined. One of these methods is potentiometric ion-selective electrodes, which have certain advantages over alternative methods in terms of multiple parameters. In this review, we provide a comprehensive description of the available cadmium(II)-selective polymeric membrane potentiometric sensors and their applications on different environmental samples. [ABSTRACT FROM AUTHOR]

BACKGROUND: Epilepsy is a neurological disorder and its treatment is carried out with anti–epileptic drugs. Carbamazepine has been in use since 1965, as a safe and effective anti–epileptic agent. In this paper, a poly(vinyl chloride) (PVC) membrane carbamazepine selective potentiometric sensor was developed for the determination of carbamazepine in pharmaceutical formulations. Carbamazepine–tetraphenylborate (CBZ–TPB) ion−pair was synthesized as an electroactive component and PVC membrane sensors were prepared with different CBZ–TPB ratios. The membrane with the best analytical properties was determined as the one with 2.0% CBZ–TPB ion–pair, 33.0% PVC and 65.0% o–nitrophenyl octyl ether (o–NPOE). RESULTS: The proposed sensor exhibited linear responses over the concentration range 1.0 × 10−5 – 1.0 × 10−2 mol L−1 (R2 = 0.999). The limit of detection was 9.60 × 10−6 mol L−1. The developed sensor showed high selectivity against carbamazepine over some ionic species investigated and also over other anti–epileptic drugs. The potentiometric response of the sensor was not affected by pH in the wide pH range of 4.0–9.0 and the response was fast, at ≈10s. CONCLUSION: The fabricated carbamazepine–selective sensor was applied for the determination of carbamazepine contents of some pharmaceutical formulations. The potentiometric measurement results for the pharmaceutical formulations gave results with good agreement with data obtained using UV–visible spectroscopy. As a result, the developed carbamazepine selective potentiometric sensor can be considered as an alternative to other analytical methods for the determination of carbamazepine in pharmaceutical samples. © 2022 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

In the present study, we developed a cadmium(II)-selective sensor using a novel poly(vinyl chloride) membrane, containing synthesised (E)-2-benzylidenehydrazinecarbothioamide as an ionophore. This newly developed cadmium(II)-selective sensor exhibits best performance with a membrane composition of poly(vinyl chloride) (PVC), bis(2-ethylhexyl) adipate (DEHA), ionophore, potassium tetrakis (p-chlorophenyl) borate (KTpClPB) at 32.0:63.0:4.0:1.0 ratio (%, w/w). The cadmium(II)-selective sensor exhibits a lower detection limit of 1.77 × 10−6 mol L−1. This potentiometric sensor displays a stable potential response in the pH range of 5.0–10.0 and it shows a good selectivity for Cd2+ in the presence of interfering ions. The developed sensor shows a relatively fast response time (10 s), good reusability and stability. The proposed cadmium(II)-selective sensor was successfully applied as an indicator electrode in potentiometric titration of Cd2+ ions with EDTA and for the direct determination of Cd2+ ions in different environmental samples and in a waste battery sample. [ABSTRACT FROM AUTHOR]

A novel poly(vinyl chloride; PVC) membrane‐based Cu(II)–selective sensor has been developed using synthesized 5,10,15,20‐tetrakis(4‐methoxycarbonylphenyl)porphyrin as an ionophore. The Cu(II)–selective sensor exhibits a Nernstian response for Cu(II) ion over a wide concentration range of 1.0 × 10−5 to 1.0 × 10−1 mol L−1 with the slope of 27.0 ± 2.5 mV/decade, and a lower limit of detection of 1.88 × 10−6 mol L−1. The novel sensor shows good repeatability and high selectivity for Cu(II) ions over other mono‐, bi‐ and trivalent cations. The sensor potential response remains unaffected by pH in the range of 4.4–10.6 and exhibits a fast response time of less than 10s. Finally the developed Cu(II)–selective sensor has been successfully used as an indicator electrode in the potentiometric titration of Cu2+ against ethylenediaminetetraacetic acid and also in the determination of Cu(II) ion concentration in different water and beverage samples. [ABSTRACT FROM AUTHOR]