Determination of Ytterbium(III) Ions in Soil and Sediment Samples by a New Polymeric Yb3+-PVC Membrane Sensor

Abstract

A polyvinyl chloride (PVC) membrane sensor for ytterbium(III) ions was prepared, based on 2,5-bis(5-tert-butyl-benzoxazol-2-yl)thiophene (BBT) as a membrane carrier. The sensor illustrates the following characteristics: a linear dynamic range of 1.0 × 10^?6 to 1.0 × 10^?2 M; a Nernstian slope of 19.7 ± 0.5 mV decade^?1; a detection limit of 4.4 × 10^?7 M; a response time of <10 s; and use for at least 2 months without any significant potential divergence in the pH range of 3.5–8.4. Moreover, the recommended selective sensor revealed a comparatively satisfactory selectivity regarding most of the alkali and alkaline earth ions and some of the transition-metal and heavy-metal ions. In fact, it was used as an indicator electrode in the Yb(III) potentiometric titration with ethylene diamine tetra-acetic acid (EDTA) and the determination of concentration of Yb(III) ions in soil and sediment samples.     

Novel Ytterbium(III) Selective Membrane Sensor Based on N‐(2‐Pyridyl)‐N′‐(2‐Methoxyphenyl)‐Thiourea as an Excellent Carrier and Its Application to Determination of Fluoride in Mouth Wash Preparation Samples

The construction, performance, and applications of a novel ytterbium(III) sensor based on N‐(2‐pyridyl)‐N′‐(2‐methoxyphenyl)‐thiourea (PMT), as an excellent carrier, in plasticized poly(vinyl chloride) PVC matrix, is described. The influences of membrane composition and pH on the potentiometric response of the sensor were investigated. The sensor exhibits a nice Nernstian response for Yb(III) ion over a wide concentration range of 4 decades of concentration (1.0×10^?6–1.0×10^?2 M), and a detection limit of 5.0×10^?7 M. The response time of the electrodes is between 8 and 10 s, depending on the concentration of ytterbium(III) ions. The proposed sensor can be used for about 8 weeks without any considerable divergence in potential. The sensor revealed very good selectivity for Yb(III) in the presence of several metal ions. The best performance was observed for the membrane containing; 30% PVC, 59% o‐nitrophenyloctyl ether (NPOE) as solvent mediator, 7% PMT, and 4% sodium tetraphenyl borate (NaTPB). It was successfully applied as indicator electrodes in the potentiometric titration of Yb(III) with EDTA and for the determination of fluoride ion in two mouth wash formulations. The proposed La(III) sensor was found to work well under laboratory conditions. It was also used as an indicator electrode in titration of a 1.0×10^?4 M of Yb(III) with a standard EDTA solution (1.0×10^?2 M). It was also used for determination of Yb(III) ion in Xenotime .     

Erbium(III) PVC Membrane Ion-Selective Sensor based on 4-(2-Thiazolylazo)resorcinal

Abstract

4-(2-Thiazolylazo)resorcinol (TR) was used as a new compound to play the role of an excellent ion carrier in the fabrication of an Er(III) membrane electrode. The electrode shows a very good selectivity toward Er(III) ions over a wide variety of cations, including alkali, alkaline earth, transition, and heavy-metal ions. The proposed sensor exhibits a Nernstian behavior (with slope of 19.6 ± 0.6 mV per decade) over a wide concentration range (1.0 × 10^?6 to 1.0 × 10^?2 M). The detection limit of the sensor is 6.6 × 10^?7 M. It has a very short response time, in the whole concentration range (～10 s), and can be used for at least 12 weeks in the pH range of 2.8–9.3. The proposed sensor was successfully applied as an indicator electrode for the potentiometric titration of a Er(III) solution, with EDTA. It was also successfully applied to the F^? ion determination in some mouthwashing solutions.     

Lanthanide Recognition: Determination of Thulium(III) Ions in Presence of Other Rare Earth Elements by a Thulium(III) Sensor Based on 4-Methyl-1,2-Bis(2-Pyridinecarboxamido)benzene as a Sensing Material

Abstract

In this research, a novel thulium(III) potentiometric membrane sensor based on 4-methyl-1,2-bis(2-pyridinecarboxamido) benzene (MPB) is described. The sensor exhibits a Nernstian response over a concentration range of 1.0 × 10^?7 M to 1.0 × 10^?1 M, with a detection limit of 9.0 × 10^?8 M. The best performance was achieved with a membrane composition of 30% PVC, 60% nitrobenzene (NB), 6% MPB, and 4% sodium tetraphenylborate (NaTPB). It was found that at the pH range of 3.6 to 9.0, the potential response of the sensor was not affected by the pH. Furthermore, the electrode presents satisfactory reproducibility, very fast response time (15 s), and relatively good discriminating ability for Tm(III) ions with respect to many common cations and lanthanide ions. The validation of the proposed electrode was tested by using Coal and Fuel Ash (FFA 1 Fly Ash) as a Certified Reference Material (CRM).     

Determination of Dysprosium(III) Ion in Soil and Sediment Samples by an Original Potentiometric Dysprosium(III) Membrane Sensor

Abstract

A PVC membrane electrode for dysprosium(III) [Dy(III)] ions was constructed, having its basis on benzoxazoleguanidine (BG) as a suitable ionophore. The sensor presents a linear dynamic range of 1.0 × 10^?6–1.0 × 10^?1 M, with a Nernstian slope of 19.5 ± 0.4 mV decade^?1 and a detection limit of 4.7 × 10^?7 M. The response time is quick (less than 10 s). It can be used in the pH range of 3.3–8.4, and its duration is at least 2 mo without any considerable, noticeable potential divergence. The recommended sensor revealed comparatively good selectivity with respect to most alkali, alkaline earth, some transition, and heavy metal ions. It was successfully employed as an indicator electrode in the potentiometric titration of Dy(III) ions with EDTA. The membrane sensor also applied to the determination of concentration of Dy(III) ions in soil and sediment samples. Validation with certified reference materials (CRMs) was also carried out.     

Samarium(III)-PVC-Membrane Sensor Based on Ethoxy-1-ethoxycarbonyl-1,2-dihydroquinoline

Abstract

2-Ethoxy-1-ethoxycarbonyl-1,2-dihydroquinoline (EED) was found to be a suitable neutral ionophore for the preparation of a highly selective samarium (Sm)(III) membrane sensor. Poly vinylchloride (PVC)–based membranes of EED with sodium tetraphenyl borate (NaTPB) as an anionic additive and dibutylphthalate (DBP), nitrobenzene (NB), and acetophenone (AP) as plasticizing solvent mediators were prepared and investigated as Sm(III) sensors. The sensor exhibited a Nernstian response over a concentration range of 1.0 × 10^?6 to 1.0 × 10^?2 M, with a detection limit of 5.0 × 10^?7 M. The best performance was achieved with a membrane composition of 30% PVC, 66% dibutyl phthalate (DBP), 2% EED, and 2% sodium tetraphenyl borate (NaTPB). It has a very short response time, in the whole concentration range (～10s), and can be used for at least 10 weeks. The proposed electrode shows a very good selectivity toward Sm(III) ions over a wide variety of cations, including alkali, alkaline earth, transition-metal, and heavy-metal ions. The sensor was applied to the determination of Sm ions in binary mixtures.     

PPb Level Monitoring of Dy(III) Ions by a Highly Sensitive and Selective Dy(III) Sensor Based on a New Asymmetrical Schiff's Base

Abstract

A Dy(III) ion‐selective membrane sensor has been fabricated from polyvinyl chloride (PVC) matrix membrane containing a new asymmetrical Schiff's base [(E)‐N‐(2‐hydroxybenzylidene)benzohydraide] or BBH as a neutral carrier, sodium tetraphenyl borate (NaTPB) as an anionic excluder and nitrobenzene (NB) as a plasticizing solvent mediator. The membrane sensor displays linear potential response in the concentration range of 1.0×10^?2–1.0×10^?6 M of Dy(III). The electrode exhibits a nice Nernstian slope of 20.1±0.8 mV/decade in the pH range of 3.0–8.0. The sensor has a relatively short response time in whole concentration ranges (<20 s). The detection limit of the proposed sensor is 8.0×10^?7 M (～128 ng/mL), and it can be used over a period of six weeks. The selectivity of the proposed sensor with respect to other cations, (alkali, alkaline earth, transition and heavy metal ions) and especially lanthanid ions, is excellent. The practical utility of the sensor has been demonstrated by using it as an indicator electrode in the potentiometric titration of Dy(III) with EDTA.     

Terbium(III) Ion-Selective Electrochemical Sensor Based on Hematoporphyrin

Abstract

A polyvinyl chloride (PVC) based membrane sensor for terbium ions was prepared by employing Hematoporphyrin (HP) as an ionophore. The sensor revealed a very good selectivity (expect for the Fe³⁺ion) with respect to common alkali, alkaline earth and heavy metal ions. The plasticized membrane electrode exhibits a Nernstian response for Tb³⁺ ions over a wide concentration range (1.0 × 10^?6 ? 1.0 × 10^?2 M) with a slope of 19.8±0.3 mV per decade and low detection limit of 7.4 × 10^?7 M. The developed sensor was used in determination of F^? in mouth wash preparation sample.     

A Novel Holmium(III) Membrane Sensor Based on N‐(1‐Thien‐2‐Ylmethylene)‐1,3‐Benzothiazol‐2‐Amine

Abstract

A novel plasticized membrane sensor for Ho(III) ions based on N‐(1‐thien‐2‐ylmethylene)‐1,3‐benzothiazol‐2‐amine (TBA) as a neutral carrier was prepared. The best performance was obtained with a membrane composition of 31% PVC, 61% benzyle acetate, 2% sodium tetra phenyl borate and 6% carrier. The electrode exhibits a Nernstian response for Ho(III) ions over a particular concentration range (1.0×10^?5?1.0×10^?2 M) with a slope of 19.7±0.2 mV decade^?1. The limit of the detection is 7.0×10^?6 M. The sensor has a response time of <15 s and a useful working pH range of 4.0–9.5. The proposed sensor discriminates relatively well towards Ho(III) ions with regard to common alkali, alkaline earth, and specially lanthanide ions. It was successfully applied as an indicator electrode in a potentiometric titration of Ho(III) ions with EDTA. It was also applied in determination of fluoride ions in a mouth wash preparation. The proposed sensor was applied for the determination of Ho(III) ion concentration in binary mixtures.     

Determination of cerium(III) ions in soil and sediment samples by Ce(III) PVC-based membrane electrode based on 2,5-dioxo-4-imidazolidinyl

2,5-Dioxo-4-imidazolidinyl was used as an excellent sensing material in the preparation of a PVC membrane for a Ce(III)-selective sensor. The electrode shows a good selectivity for the Ce(III) ion with respect to most common cations including alkali, alkaline earth, transition, and heavy metal ions. The developed sensor exhibits a wide linear response with a slope of 19.6?±?0.3 mV per decade over the concentration range of 1.0?×?10^?6 to 1.0?×?10^?1 M, while the illustrated detection limit is 5.7?×?10^?7 M of Ce(III) ions. Moreover, it is concluded that the sensor response is pH-independent in the range of 3.1–9.8. The applications of the recommended electrode include the determination of concentration of Ce(III) ions in soil and sediment samples, validation with CRM's, and the Ce(III) ion potentiometric titration with EDTA as an indicator electrode.     

Application of Novel Praseodymium (III) PVC‐Membrane Electrode for Determination of Pr(III) Ions in Soil and Sediment Samples

Abstract

A novel Pr(III) ion‐selective polyvinyl chloride (PVC) membrane sensor, based on N,N‐bis(α‐methylsalicylidene)diethylenetriamine (BMT) as a new ionophore, has been prepared and studied. The electrode showed good selectivity for Pr(III) ion with respect to most common cations, including alkali, alkaline earth, transition, and heavy metal ions. This electrode has a wide linear dynamic range from 1.0×10^?6 to 1.0×10^?2 M with a Nernstian slope of 19.8±0.2 mV per decade and a low detection limit of 6.5×10^?7 M, in the pH range of 3.0–8.4, while response time was rapid (<15 s). As far as applications of the recommended sensor are concerned, first it was employed as an indicator electrode in the potentiometric titration of Pr(III) ions with EDTA. Second, it was effectively applied to the determination of concentration of Pr(III) ions in soil and sediment samples, and validation with CRMs.     

1,3,4-Trisubstituted-2-azetidinone Derivatives as Novel Receptors for Bismuth(III) Ion-Selective Electrodes: Application in Pharmaceutical and Glass Samples

Abstract

Polymeric membrane electrodes (PMEs) and coated graphite electrodes (CGEs) containing 1,3,4-trisubstituted-2-azetidinone derivatives as ion carriers are reported here for bismuth(III) ion selectivity. These electrodes exhibited Nernstian response for Bi³⁺ ions over a wide concentration range (5.0 × 10^?7 M to 1.0 × 10^?1 M for CGE) with a lower detection limit of 3.98 × 10^?7 M (for CGE) and wide pH range (1.3–5.0). Compared to polymeric membrane electrode, the coated graphite electrode has shown better selectivity for Bi³⁺ ions with respect to common metal ions. Proposed electrodes have been used for the estimation of Bi³⁺ ions in pharmaceutical and glass samples.     

Tb3+ PVC-Membrane Electrode Based on 2-{2-(2-Anilinocarbothioyl)hydrazino)-2-oxoacetyl}-N-phenyl-1-hydrazine Carbothioamide

Abstract

The polyvinyl chloride (PVC) membrane containing 2-{2-(2-anilinocarbothioyl)hydrazino)-2-oxoacetyl}-N-phenyl-1-hydrazinecarbothioamide (AHC) as a suitable iophore exhibits a Nernstian response for Tb³⁺ ions over a wide concentration range (1.0 × 10^?6 to 1.0 × 10^?2 M) with a slope of 19.6 ± 0.3 mV per decade and a limit of detection of 6.8 × 10^?7 M in the pH range 3.5–8.5. The proposed sensor revealed very good selectivities (expect for the Pr³⁺ and Ho³⁺ ions) for a wide variety of other metal ions. The practical utility of the electrodes has been demonstrated by its use for the determination of Tb³⁺ in different solutions.     

Novel Dy(III) Sensor Based on a New Bis‐Pyrrolidene Schiff's Base

In this work a dysprosium [Dy(III)]‐selective solvent polymeric membrane sensor based on N,N‐bis(pyrrolidene) benzne‐1,2‐diamine, poly(vinyl chloride)(PVC), the plasticizer benzylacetate (BA), and anionic site is described. This sensor responds to Dy(III) activity in a linear range from 1.0×10^?5 to 1.0×10^?1 M, with a slope of 20.6±0.2 mV per decade and a detection limit of 6.0×10^?6 M at the pH range of 3.5–8.0. It has a fast response time of<20 s in the entire concentration range, and can be used for at least 2 months without any considerable divergence in the electrode potentials. The proposed sensor revealed comparatively good selectivity with respect to common alkali, alkaline earth, transition and heavy metal ions. It was used as an indicator electrode in the potentiometric titration of fluoride ions and in determination of concentration of F ^– ions in some mouth washing solutions.     

Cobalt(II)-selective membrane electrode based on N,N′-di(thiazol-2-yl)formimidamide

A new PVC-membrane electrode for Co²⁺ ions based on N,N′-di(thiazol-2-yl)formimidamide (TF) as membrane carrier has been developed. The electrode resulted in Nernstian response (29.5?±?0.4?mV decade^?1) for Co²⁺ ion over a wide concentration range (2.5?×?10^?7 ?1.0?×?10^?1?M) with a detection limit of 6.1?×?10^?8?M. The sensor has a response time of about 10?s, and can be used for at least 2 months without observing any deviation from the Nernstain response. The electrode revealed good selectivity towards cobalt(II) ion over a wide variety of alkali, alkaline earth, transition, and heavy metal ions and could be used in the pH range 2.0–7.0. The electrode was used for determination of Co²⁺ in real samples.     

Determination of Fluoride Ions in Mouthwash Samples by a PVC Membrane Samarium(III) Sensor

Abstract

In this study, a new ion-selective electrode for Sm³⁺ is described, illustrating 2-[(E)-1-(1H-pyrrol-2-yl)methylidene]-1-hydrazinecarbothioamide (PMH) in a poly(vinylchloride) (PVC) membrane with nitrobenzene (NB) as a plasticizer and sodium tetraphenyl borate (NaTPB) as an anionic additive. The proposed sensor exhibited a Nernstian response for Sm³⁺ ions over a wide concentration range between 1.0 × 10^?2 and 1 × 10^?6 M, with a detection limit of 5.2 × 10^?7 M in the pH range of 4.2–8.5. Moreover, the sensor displayed the Nernstian slope of 19.8 ± 0.3 mV per decade, having a fast response time within 10 s over the entire concentration range. This electrode presented very good selectivity and sensitivity toward the Sm³⁺ ions over a wide variety of cations, including alkali, alkaline earth, transition-metal, and heavy-metal ions. It was used as an indicator electrode in the potentiometric titration of Sm³⁺ ions with EDTA. The membrane sensor was also applied to the determination of fluoride ions in mouthwash samples.     

Thulium(III) Ions Monitoring by a Novel Thulium(III) Microelectrode Based on a S‐N Schiff Base

This study presents for the first time development of a highly selective and sensitive thulium(III) micro‐sensor. Theoretical calculations were conducted on a S‐N Schiff base [thiophene‐2‐carbaldehyde‐(7‐methyl‐1,3‐benzothiazol‐2‐yl) hydrazone] (TCMH) in order to obtain a clue about the tendency of TCMH to Tm(III) and some other metal ions. Then, TCMH was used as a membrane‐active component to prepare a Tm(III)‐selective polymeric membrane microelectrode. In line with the resulting data, the electrode exhibits a Nernstian response toward Tm(III) ions for a very wide concentration range (1.0×10^?11–4.0×10^?6 M) with a detection limit of 1.0×10^?11 (ca. 1.5 ppt) and a very fast response time in the whole concentration range (<5 s). In addition, the results showed that the certain microelectrode could be applied in the pH range of 4.0–11.0 with a usage of more than one month without any considerable potential divergence.     

Fe(III) Ion‐Selective Membrane Electrode Based on 4‐Amino‐6‐methyl‐3‐methylmercapto‐1,2,4‐triazin‐5‐one

Abstract

An original highly selective and sensitive PVC membrane sensor, working as a Fe(III) ion selective electrode and using 4‐amino‐6‐methyl‐3‐methylmercapto‐1,2,4‐triazin‐5‐one (AMMTO) as an ionophore, has been developed. This cetain sensor demonstrated the following performance; a linear dynamic range between 1.0×10^?6 and 1.0×10^?1 M with a near Nernstian slope of 19.4±0.5 mV per decade; a detection limit of 6.8×10^?7 M; characteristically, the best performance was obtained with a membrane composition of 30% poly(vinyl chloride), 65.5% nitrophenyl octyl ether, 2% sodium tetraphenyl borate and 2.5% AMMTO. Furthermore, the potentiometric response of the developed electrode is independent of the solution pH in the range of 2.2–4.8. The sensor possesses the advantages of short conditioning time, fast response time (<15 s) and, especially, great selectivity towards transition and heavy metal ions and some mono, di‐ and trivalent cations. The electrode can be used for at least 9 weeks without any considerable potential divergence. It was effectively used as an indicator electrode in the potentiometric titration of Fe(III) ions with EDTA and the direct determination of Fe³⁺ in different water samples.     

Lanthanide Recognition: Development of an Asymetric Gadolinium Microsensor Based on N-(2-pyridyl)-N′-(4-nitrophenyl)thiourea

Abstract

The first asymmetric potentiometric Gd(III) microsensor is reported here. N-(2-Pyridyl)-N′-(4-nitrophenyl)thiourea (PyTu₄NO₂) was found to have a very selective and sensitive behavior toward Gd(III) ions, in comparison to other lanthanide ions as well as inner transition and representative metal ions and hence was used as a sensing material in the construction of a Gd(III) microelectrode. The Gd(III) sensor exhibits a Nernstian slope of 17.46 ± 0.3 mV per decade over the concentration range of 1.0 × 10^?8 to 1.0 × 10^?3 M and a detection limit of 3.0 × 10^?9 M of Gd(III) ions. The potentiometric response of the sensor is independent of the solution pH in the range of 4.0–9.0. It manifests advantages of low detection limit and fast response time (10–15 s).     

Construction of a new solid-state U(VI) ion-selective electrode based on polypyrrole conducting polymer

In this study, a potentiometric sensor based on a pencil graphite electrode (PGE) coated with polypyrrole doped with uranyl zinc acetate (termed PGE/PPy/U) have been prepared for potentiometric determination of uranyl in aqueous solutions. Electropolymerization reaction for preparing of U(VI) sensor electrode was carried via applying a constant current of 1.0 mA on PGA working electrode in a solution containing 8.0 mM pyrrole and 0.8 mM ZnUO₂(CH₃COO)₄ salt. The constructed electrode displayed a linear and near Nernstian response (22.60 ± 0.40 mV/decade) to U(VI) ions in the concentration range of 1.0 × 10^?6–1.0 × 10^?2 M. A detection limit of 6.30 × 10^?7 M and a fast response time (≤12 s) was observed during measurements. The working pH range of the electrode was 4.0–8.0 and lifetime of the sensor was at least 60 days. The electrode revealed good selectivity with respect to many cations including alkali, alkaline earth, transition and heavy metal ions. The introduced uranyl electrode was used for measurement of U(VI) ion in real samples without any serious inferences from other ions.