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.     

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.     

Procaine as a Sensing Material for Determination of Dysprosium(III) Ions in Presence of Other Rare‐earth Elements in Biological and Environmental Samples

Abstract

The biological properties of the lanthanides, primarily based on their similarity to calcium, have been the basis for research into potential therapeutic applications of lanthanides since the early part of the twentieth century. In this research, procaine was used as a sensing material in construction of a new Dy(III) potentiometric membrane sensor. The sensor exhibits a Nernstian response over a concentration range of 1.0×10^?6 mol l^?1?1.0×10^?1 mol l^?1, with a detection limit of 7.9×10^?7 mol L^?1. The best performance was achieved with a membrane composition, consisting of 30% PVC, 63% dibutylphthalate (DBP), 5% procaine and 2% sodium tetraphenylborate (NaTPB). It was found that at the pH range of 4.0–8.0, the potential response of the sensor was not affected by the pH. Furthermore, the electrode presents satisfactory reproducibility, very fast response time (<10 s) and relatively good discriminating ability for Dy(III) ions with respect to many common cations and other lanthanide ions. The sensor has been applied to the determination of Dy(III) in human serum and in soil and sediment samples. Validation with Certified Reference Material (CRM) was also done.     

Novel Potentiometric PVC‐Membrane and Coated Graphite Sensors for Lanthanum(III)

Preliminary theoretical studies revealed the selective complexation of bis (2‐mercaptoanil) diacetyl (BMDA) with La³⁺ over several alkali, alkaline earth and heavy metal ions. Thus, novel PVC‐based membrane (PBM) and coated graphite membrane (CGM) sensors for La(III) based on BMDA were prepared. The electrodes display Nernstian behavior over wide concentration ranges (i.e., 1.0×10^?5–1.0×10^?1 M for PBM and 1.0×10^?6–1.0×10^?1 M for CGM). The potential response of sensors was pH independent in the range of 4.0–8.0. The sensors possess satisfactory reproducibility, fast response time (<15 s), and specially excellent discriminating ability for La³⁺ ions with respect to most of the cations. The membrane sensor was used as an indicator electrode in potentiometric titration of lanthanum ions with EDTA. The coated graphite membrane electrode was applied in determination of fluoride ions in mouth wash preparations.     

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).     

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.     

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.     

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.     

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.     

Construction of a Highly Selective and Sensitive La(III) Sensor Based on N‐(2‐Pyridyl)‐N′‐(4‐methoxyphenyl)‐thiourea for Nano Level Monitoring of La(III) Ions

N‐(2‐Pyridyl)‐N′‐(4‐methoxyphenyl)‐thiourea (PMPT) was found to be a suitable neutral ion carrier for the construction of a highly selective and sensitive La(III) membrane sensor. Poly(vinyl chloride) (PVC) based membranes of PMPT with potassium tetrakis (p‐chlorophenyl) borate (KTpClPB) as an anionic excluder and oleic acid (OA), dibutyl phthalate (DBP), benzyl acetate (BA) and o‐nitrophenyloctyl ether (NPOE) as plasticizing solvent mediators were constructed and investigated as La(III) membrane sensors. A membrane composed of PMPT‐PVC‐KTpClPB‐BA with the ratio 8.0 : 35.0 : 3.0 : 54.0 works well over a very wide concentration range (4.0×10^?8 to 1.0×10^?1 M) with a Nernstian slope of 19.6±0.2 mV per decade of activity between pH values of 4.0 and 9.0. The detection limit of the sensor was calculated to be 2.0×10^?8 M (ca. 3.0 ppb). The sensor displays very good discrimination toward La(III) ions with regard to most common metal ions and lanthanide ions. The proposed sensor shows a short response time for whole concentration range (ca. 12 s). For evaluation of the analytical applicability of the La(III) sensor, it was successfully used as an indicator electrode for the titration of La(III) ions with EDTA. It was also applied to the determination of fluoride content of two mouth wash preparation samples and monitoring of La(III) ions in some binary and ternary mixtures.     

A New Pentadentate S‐N Schiffs' Base as a Novel Ionophore in Construction of a Novel Gd(III) Membrane Sensor

We found that bis(thiophenal) pyridine‐2,6‐diamine (BPD) can be used as an excellent ion carrier to prepare a gadolinium‐selective PVC‐based membrane sensor. The use of oleic acid (OA) and potassium tetrakis(p‐chlorophenyl borate)(KTKpClPB), as anionic additives, and dibutyl phthalate (DBP), acetophenone (AP) and nitrobenzene (NB), as plasticizing solvent mediators was investigated. The best performance was observed with a membrane having the composition of 30% PVC; 62% BA; 5% BPD; and 3% KTKpClPB. The resulting sensor works well over a relatively wide concentration range (1.0×10^?6–1.0×10^?1 M) with a Nernstian slope of 19.4±0.4 mV per decade of gadolinium activity over a wide pH range (3.5–8.0). The limit of detection of the sensor is 7.0×10^?7 M (ca. 110 ng mL^?1). The proposed electrode shows excellent discriminating ability toward gadolinium ions with regard to common alkali, alkaline earth, transition, heavy metal ions, and specially, lanthanide ions. The proposed sensor was applied as an indicator electrode for titration of gadolinium ions 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.     

Development of Pr(III) Selective Electrode Using 1,6,7,12‐Tetramine‐2,5,8,11‐tetraoxo‐1(12),6(7)‐di(biphenyl)‐dodecane (TATODBDD) as a Neutral Carrier

A polyvinyl chloride (PVC) membrane based Pr(III) selective electrode was constructed using 1,6,7,12‐tetramine‐2,5,8,11‐tetraoxo‐1(12),6(7)‐di(biphenyl)dodecane (TATODBDD) as a neutral carrier. The sensor exhibits a Nernstian response for Pr(III) ions, a wide concentration range of 3.9×10^?7?1.0×10^?1 mol/L with a detection limit of 5.0×10^?8 mol/L and slope of 19.5 mV/decade. The developed sensor revealed relatively good selectivity and high sensitivity for Pr(III) ions over the other lanthanide ions. The potentiometric response of the sensor is independent in the pH range 2.9–9.5. The advantages of sensor are low resistance, very fast response time (<10 s) with good selectivity. This sensor can be used up to 6 weeks without any divergences in potential response.     

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.     

Chromium(III) Potentiometric Sensor Based on Para‐Tertiary‐Butyl Calix[4]arene

A new chromium(III) PVC membrane sensor incorporating p‐tertiary‐butyl calix[4]arene as ionophore, potassium tetrakis as additive and dibutyl phthalate (DBP) as plasticizer was constructed. The electrode exhibited an excellent potentiometric response over a wide concentration range of 1.0×10^?7–1.0×10^?1 M with a Nernstian slope of 20±0.5 mV per decade. The detection limit was 5.0×10^?8 M. The electrode showed a better performance over a pH range of 3.0–8.0, and had a short response time of about <15 s.The electrode was successfully applied to potentiometric titration of Cr (III) with EDTA and for direct determination of chromium(III) in waste water.     

Chromium(III) Ion Selective Electrode Based on Oxalic Acid Bis(Cyclohexylidene Hydrazide)

A poly(vinyl chloride) membrane sensor based on oxalic acid bis (cyclohexylidene hydrazide) as membrane carrier was prepared and investigated as a Cr(III)‐selective electrode. The electrode reveals a Nernstian behavior (slope 19.8±0.4 mV decade^?1) over a wide Cr(III) ion concentration range 1.0×10^?7–1.0×10^?2 mol dm^?3 with a very low limit of detection (i.e., down to 6.3×10^?8 mol dm^?3). The potentiometric response of the sensor is independent of the pH of the test solution in the pH range 1.7–6.5. The electrode possesses advantage of very fast response, relatively long lifetime and especially good selectivity to wide variety of other cations. The sensor was used as an indicator electrode, in the potentiometric titration of chromium ion and in the determination of Cr(III) in waste water and alloy samples.     

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.     

Original Potentiometric Ytterbium(III) PVC-Membrane Sensor Based on N1,N2-Bis-[1-(2-hydroxy-1,2-diphenyl)ethylidene]ethanedihydrazide

Abstract

In this work, we describe the construction, performance, and applications of an original ytterbium(III) sensor based on N¹,N²-bis-[1-(2-hydroxy-1,2-diphenyl)ethylidene]ethanedihydrazide (BHDEH), which acts as a suitable carrier. Because it has a low detection limit of 4.2 × 10^?7 M, the sensor response for the Yb(III) ion is Nernstian over a wide concentration range: four decades of concentration (1.0 × 10^?6 to 1.0 × 10^?2 M). The response time of the electrode is less than 10 s, it can be used in the pH range of 3.2–8.3, and its duration is at least 2 months without any considerable potential divergence. The sensor revealed very good selectivity for Yb(III) in the presence of several metal ions. To investigate the sensor analytical applicability, it was tested as an indicator electrode in the potentiometric titration of Yb(III) solution with standard EDTA solution. The proposed electrode was also used to determine fluoride ions in mouthwash.     

Novel Bromide PVC‐Based Membrane Sensor Based on Iron(III)‐Salen

A novel bromide PVC‐based membrane sensor, based on iron(III)‐salen (IS) as an electroactive material, is successfully developed. The sensor possesses the advantages of low detection limit (6.0×10^?6), wide working concentration range (7.0×10^?6–1.0×10^?1 M), Nernstian behavior (slope of 59.0±0.5 mV per decade), low response time (<15 s), wide working pH range (3–9), and specially, high bromide selectivity over a wide variety of organic and inorganic anions, specially iodide, chloride, and hydroxide ions. The electrode was used in the direct potentiometric determination of hyoscine butylbromide, and as an indicator electrode in potentiometric titration of bromide ions with silver ions.     

A Novel Al(III)‐Selective Electrochemical Sensor Based on N,N′‐Bis(salicylidene)‐1,2‐phenylenediamine Complexes

A polyvinylchloride membrane sensor based on N,N′‐bis(salecylidene)‐1,2‐phenylenediamine (salophen) as membrane carrier was prepared and investigated as a Al³⁺‐selective electrode. The sensor exhibits a Nernstian response toward Al(III) over a wide concentration range (8.0×10^?7–3.0×10^?2 M), with a detection limit of 6.0×10^?7 M. The potentiometric response of the sensor is independent of the pH of the test solution in the pH range 3.2–4.5. The electrode possesses advantages of very fast response and high selectivity for Al³⁺ in comparison with alkali, alkaline earth and some heavy metal ions. The sensor was used as an indicator electrode, in the potentiometric titration of aluminum ion and in determination of Al³⁺ contents in drug, water and waste water samples.