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Elisa Rasouli,1 Wan Jeffrey Basirun,2 Majid Rezayi,3,4 Kamyar Shameli,5 Esmail Nourmohammadi,6 Roshanak Khandanlou,7 Zahra Izadiyan,5 Hoda Khoshdel Sarkarizi8 1Nanotechnology & Catalysis Research Centre, Institute of Postgraduate Studies, University of Malaya, Kuala Lumpur, Malaysia; 2Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia; 3Medical Toxicology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran; 4Department of Modern Sciences and Technologies, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran; 5Malaysia-Japan International Institute of Technology, University Technology Malaysia, Kuala Lumpur, Malaysia; 6Department of Medical Biotechnology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran; 7School of Psychological and Clinical Sciences, Faculty of Engineering, Health, Science and the Environment, Charles Darwin University, Darwin, NT, Australia; 8Department of Anatomical Sciences and Cell Biology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran Introduction: In the present research, we report a quick and green synthesis of magnetite nanoparticles (Fe3O4-NPs) in aqueous solution using ferric and ferrous chloride, with different percentages of natural honey (0.5%, 1.0%, 3.0% and 5.0% w/v) as the precursors, stabilizer, reducing and capping agent, respectively. The effect of the stabilizer on the magnetic properties and size of Fe3O4-NPs was also studied. Methods: The nanoparticles were characterized by X-ray diffraction (XRD) analysis, field emission scanning electron microscopy, energy dispersive X-ray fluorescence, transmission electron microscopy (TEM), vibrating sample magnetometry (VSM) and Fourier transform infrared spectroscopy. Results: The XRD analysis indicated the presence of pure Fe3O4-NPs while the TEM images indicated that the Fe3O4-NPs are spherical with a diameter range between 3.21 and 2.22 nm. The VSM

Elisa Rasouli,1 Wan Jeffrey Basirun,2 Majid Rezayi,3,4 Kamyar Shameli,5 Esmail Nourmohammadi,6 Roshanak Khandanlou,7 Zahra Izadiyan,5 Hoda Khoshdel Sarkarizi8 1Nanotechnology & Catalysis Research Centre, Institute of Postgraduate Studies, University of Malaya, Kuala Lumpur, Malaysia; 2Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia; 3Medical Toxicology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran; 4Department of Modern Sciences and Technologies, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran; 5Malaysia-Japan International Institute of Technology, University Technology Malaysia, Kuala Lumpur, Malaysia; 6Department of Medical Biotechnology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran; 7School of Psychological and Clinical Sciences, Faculty of Engineering, Health, Science and the Environment, Charles Darwin University, Darwin, NT, Australia; 8Department of Anatomical Sciences and Cell Biology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran Introduction: In the present research, we report a quick and green synthesis of magnetite nanoparticles (Fe3O4-NPs) in aqueous solution using ferric and ferrous chloride, with different percentages of natural honey (0.5%, 1.0%, 3.0% and 5.0% w/v) as the precursors, stabilizer, reducing and capping agent, respectively. The effect of the stabilizer on the magnetic properties and size of Fe3O4-NPs was also studied. Methods: The nanoparticles were characterized by X-ray diffraction (XRD) analysis, field emission scanning electron microscopy, energy dispersive X-ray fluorescence, transmission electron microscopy (TEM), vibrating sample magnetometry (VSM) and Fourier transform infrared spectroscopy. Results: The XRD analysis indicated the presence of pure Fe3O4-NPs while the TEM images indicated that the Fe3O4-NPs are spherical with a diameter range between 3.21 and 2.22 nm. The VSM

Environmental organic pollutants are mineralized to harmless final-products such H2O and CO2 by photocatalytic advanced oxidation processes (AOPs). In photocatalytic-AOPs, an appropriate concentration of p-Cresol was mixed with certain amount of ZnO in 500 mL deionized water according to an experimental-design. Then the mixture was irradiated by UV-A lamp at different pH for 6 h. At specific time intervals, the sampling was carried out to calculate the efficiency of the photodegradation. Therefore, the photodegradation as a system consists of four input variables such irradiation time, pH, amount of ZnO and p-Cresol’s concentration while the only output was the efficiency. In this work, the system was modeled and optimized by semi-empirical response surface methodology. To obtain the empirical responses, the design was performed in laboratory. Then observed responses were fitted with several well-known models by regression process to suggest a provisional model. The suggested model which was validated by several statistical evidence, predicted the desirable condition with higher efficiency. The predicted condition consisted of irradiation time (280 min), pH (7.9), photocatalyst (1.5 g L−1), p-Cresol (95 mg L−1) and efficiency (95%) which confirmed by further experiments. The closed confirmation results has presented the removal (efficiency = 94.7%) of higher p-Cresol concentration (95 mg L−1) at shorter irradiation time in comparison with the normal photodegradation efficiency (97%) which included irradiation time (300 min), pH (7.5), photocatalyst amount (1.5 g L−1) and p-Cresol (75 mg L−1). As a conclusion, the modeling which is able to industrial scale up succeeded to remove higher concentration of environmental organic pollutants with ignorable reduction of efficiency.

Environmental organic pollutants are mineralized to harmless final-products such H2O and CO2 by photocatalytic advanced oxidation processes (AOPs). In photocatalytic-AOPs, an appropriate concentration of p-Cresol was mixed with certain amount of ZnO in 500 mL deionized water according to an experimental-design. Then the mixture was irradiated by UV-A lamp at different pH for 6 h. At specific time intervals, the sampling was carried out to calculate the efficiency of the photodegradation. Therefore, the photodegradation as a system consists of four input variables such irradiation time, pH, amount of ZnO and p-Cresol’s concentration while the only output was the efficiency. In this work, the system was modeled and optimized by semi-empirical response surface methodology. To obtain the empirical responses, the design was performed in laboratory. Then observed responses were fitted with several well-known models by regression process to suggest a provisional model. The suggested model which was validated by several statistical evidence, predicted the desirable condition with higher efficiency. The predicted condition consisted of irradiation time (280 min), pH (7.9), photocatalyst (1.5 g L−1), p-Cresol (95 mg L−1) and efficiency (95%) which confirmed by further experiments. The closed confirmation results has presented the removal (efficiency = 94.7%) of higher p-Cresol concentration (95 mg L−1) at shorter irradiation time in comparison with the normal photodegradation efficiency (97%) which included irradiation time (300 min), pH (7.5), photocatalyst amount (1.5 g L−1) and p-Cresol (75 mg L−1). As a conclusion, the modeling which is able to industrial scale up succeeded to remove higher concentration of environmental organic pollutants with ignorable reduction of efficiency.

As a novel renewable resource, Jatropha curcas seed oil with an iodine value of 103.57g/100g, and containing almost 44.7% oleic acid, 32.8% linoleic acid as the dominant fatty acids, 13.78% palmitic acid, 6.92% stearic acid and 0.71% palmitoleic acid was epoxidized using hydrogen peroxide as oxygen donor and lauric acid as an active oxygen carrier in the presence of immobilized Candida antarctica Lipase B. In the present work the effects of variables (reaction temperature, enzyme load, the mole ratio of H2O2: C=C bonds, lauric acid load and reaction time) on the oxygen oxirane content (OOC) of epoxidized Jatropha curcas were investigated. The process was optimized for the enzymatic epoxidation of Jatropha oil, with the theoretical maximum OOC equal to 6.13%. The OOC of epoxidized Jatropha oil was 5.67% and a percentage relative conversion to oxirane(RCO) was 93.64 % under the following conditions:50C (temperature), 7% enzyme load (relative to the weight of Jatropha of oil), 3.5:1 mol ratio of H2O2: C=C bonds, 23% lauric acid load (relative to the weight of Jatropha oil) and 7.5 h (reaction time).

As a novel renewable resource, Jatropha curcas seed oil with an iodine value of 103.57g/100g, and containing almost 44.7% oleic acid, 32.8% linoleic acid as the dominant fatty acids, 13.78% palmitic acid, 6.92% stearic acid and 0.71% palmitoleic acid was epoxidized using hydrogen peroxide as oxygen donor and lauric acid as an active oxygen carrier in the presence of immobilized Candida antarctica Lipase B. In the present work the effects of variables (reaction temperature, enzyme load, the mole ratio of H2O2: C=C bonds, lauric acid load and reaction time) on the oxygen oxirane content (OOC) of epoxidized Jatropha curcas were investigated. The process was optimized for the enzymatic epoxidation of Jatropha oil, with the theoretical maximum OOC equal to 6.13%. The OOC of epoxidized Jatropha oil was 5.67% and a percentage relative conversion to oxirane(RCO) was 93.64 % under the following conditions:50C (temperature), 7% enzyme load (relative to the weight of Jatropha of oil), 3.5:1 mol ratio of H2O2: C=C bonds, 23% lauric acid load (relative to the weight of Jatropha oil) and 7.5 h (reaction time).

Hydroxamic acids and their derivatives have low toxicities and show wide range of biological activities. Copper complexes of phenyl fatty hydroxamic acids (Cu-PFHs) were prepared in a biphasic organic / aqueous medium from phenyl fatty hydroxamic acids (PFHAs) and copper nitrate. The products were separated by decantation of organic phase from aqueous phase followed by evaporation of the solvent. Elemental analysis, UV-Vis spectra and FTIR spectra showed that Cu-PFHs were formed in the solution from the complexation of PFHAs and copper ion. The antibacterial activity of PFHAs and Cu-PFHs from canola and palm kernel oils were investigated against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) using well diffusion method. The results showed that Cu-PFHs have higher antibacterial activity compared to PFHAs. Antibacterial activity of Cu-PHAs from canola oil against E.coli was significantly higher than hloramphenicol and cefotaxime.

Calixresorcinarenes have proved to be unique molecules for molecular recognition via hydrogen bonding, hydrophobic and ionic interactions with suitable substrates such as cations. The study of the interactions involved in the complexation of different cations with calixresorcinarenes in solvent mixtures is important for a better understanding of the mechanism of biological transport, molecular recognition, and other analytical applications. This article summarizes different aspects of the complexes of the Ti3+ metal cation with c-methylcalix[4]resorcinarene (CMCR) as studied by conductometry in acetonitrile (AN)–water (H2O) binary mixtures at different temperatures. Conductance data show that the metal cation/ligand (ML) stoichiometry of the complexes in solution is 1:1 in all cases. Non-linear behaviour was observed for the variation of logKf of the complexes vs. the composition of the binary solvent mixtures. Selectivity of CMCR for the Ti3+ cation is sensitive to solvent composition; in some cases and at certain compositions of the mixed solvent systems, the selectivity order is changed. Values of thermodynamic parameters (,) for formation of the CMCR–Ti3+ complexes in AN–H2O binary systems were obtained from the temperature dependence of stability constants, and the results show that the thermodynamics of complexation reactions are affected by the nature and composition of the mixed solvents.

Phenyl fatty hydroxamic acids (PFHAs) were synthesized by phenyl hydroxylaminolysis of canola or palm kernel oils using lipozyme TL IM as catalyst. Copper complexes of phenyl fatty hydroxamic acids (copper phenyl fatty hydroxamate (Cu-PFHs)) acids were prepared by stirring the phenyl fatty hydroxamic acids which were dissolved in hexane and copper(II) nitrate solution. The antifungal properties of phenyl fatty hydroxamic acids and its copper(II) complex Cu-PFHs based on canola and palm kernel oils were separately investigated against Candida parapsilosis, Candida albicans and Aspergillus fumigatus by the disc diffusion method using Mueller-Hinton agar. The results showed that antifungal activity of Cu-PFHs is higher than phenyl fatty hydroxamic acids do and also the activity of phenyl fatty hydroxamic acids and Cu-PFHs increase while their concentrations increase. The antifungal activity of phenyl fatty hydroxamic acids and Cu-PFHs are significantly higher than nystatin while use against the A. fumigatus, C. parapsilosis and C. albicans and also are significantly higher than ketoconazole while use against the A. fumigatus.

Hydroxamic acids and their derivatives have low toxicities and show wide range of biological activities. Copper complexes of phenyl fatty hydroxamic acids (Cu-PFHs) were prepared in a biphasic organic / aqueous medium from phenyl fatty hydroxamic acids (PFHAs) and copper nitrate. The products were separated by decantation of organic phase from aqueous phase followed by evaporation of the solvent. Elemental analysis, UV-Vis spectra and FTIR spectra showed that Cu-PFHs were formed in the solution from the complexation of PFHAs and copper ion. The antibacterial activity of PFHAs and Cu-PFHs from canola and palm kernel oils were investigated against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) using well diffusion method. The results showed that Cu-PFHs have higher antibacterial activity compared to PFHAs. Antibacterial activity of Cu-PHAs from canola oil against E.coli was significantly higher than hloramphenicol and cefotaxime.

Calixresorcinarenes have proved to be unique molecules for molecular recognition via hydrogen bonding, hydrophobic and ionic interactions with suitable substrates such as cations. The study of the interactions involved in the complexation of different cations with calixresorcinarenes in solvent mixtures is important for a better understanding of the mechanism of biological transport, molecular recognition, and other analytical applications. This article summarizes different aspects of the complexes of the Ti3+ metal cation with c-methylcalix[4]resorcinarene (CMCR) as studied by conductometry in acetonitrile (AN)–water (H2O) binary mixtures at different temperatures. Conductance data show that the metal cation/ligand (ML) stoichiometry of the complexes in solution is 1:1 in all cases. Non-linear behaviour was observed for the variation of logKf of the complexes vs. the composition of the binary solvent mixtures. Selectivity of CMCR for the Ti3+ cation is sensitive to solvent composition; in some cases and at certain compositions of the mixed solvent systems, the selectivity order is changed. Values of thermodynamic parameters (,) for formation of the CMCR–Ti3+ complexes in AN–H2O binary systems were obtained from the temperature dependence of stability constants, and the results show that the thermodynamics of complexation reactions are affected by the nature and composition of the mixed solvents.

Phenyl fatty hydroxamic acids (PFHAs) were synthesized by phenyl hydroxylaminolysis of canola or palm kernel oils using lipozyme TL IM as catalyst. Copper complexes of phenyl fatty hydroxamic acids (copper phenyl fatty hydroxamate (Cu-PFHs)) acids were prepared by stirring the phenyl fatty hydroxamic acids which were dissolved in hexane and copper(II) nitrate solution. The antifungal properties of phenyl fatty hydroxamic acids and its copper(II) complex Cu-PFHs based on canola and palm kernel oils were separately investigated against Candida parapsilosis, Candida albicans and Aspergillus fumigatus by the disc diffusion method using Mueller-Hinton agar. The results showed that antifungal activity of Cu-PFHs is higher than phenyl fatty hydroxamic acids do and also the activity of phenyl fatty hydroxamic acids and Cu-PFHs increase while their concentrations increase. The antifungal activity of phenyl fatty hydroxamic acids and Cu-PFHs are significantly higher than nystatin while use against the A. fumigatus, C. parapsilosis and C. albicans and also are significantly higher than ketoconazole while use against the A. fumigatus.

Novel ionophores comprising various hydroxide and amine structures were immobilized onto poly(vinyl chloride) (PVC) matrices, and these were examined to determine Ti(III) selectivity. To predict the selectivity of Ti(III), a PVC membrane was used to investigate the binding of Ti(III) to c-methylcalix[4]resorcinarene (CMCR). The study showed that the chelating ligand, CMCR, was coordinated selectively to Ti(III) at eight coordination sites involving the oxygen atoms at the interface of the membrane/solution. The membrane was prepared, based on CMCR as an ionophore, sodium tetrakis(4-fluorophenyl) borate (NaTFPB) as a lipophilic ionic additive, and dioctylphthalate (DOP) as a plasticizer. The immobilization of the ionophore and surface characterization studies revealed that the performance of CMCR-immobilized PVC was equivalent to that of mobile ionophores in supported liquid membranes (SLMs). The strengths of the ion-ionophore (CMCR-Ti(OH)(OH2)52+) interactions and the role of ionophores on membranes were studied via UV-Vis, Fourier transform infrared spectroscopy (FT–IR), scanning electron microscopy (SEM) and and X-ray diffraction (XRD).

Novel ionophores comprising various hydroxide and amine structures were immobilized onto poly(vinyl chloride) (PVC) matrices, and these were examined to determine Ti(III) selectivity. To predict the selectivity of Ti(III), a PVC membrane was used to investigate the binding of Ti(III) to c-methylcalix[4]resorcinarene (CMCR). The study showed that the chelating ligand, CMCR, was coordinated selectively to Ti(III) at eight coordination sites involving the oxygen atoms at the interface of the membrane/solution. The membrane was prepared, based on CMCR as an ionophore, sodium tetrakis(4-fluorophenyl) borate (NaTFPB) as a lipophilic ionic additive, and dioctylphthalate (DOP) as a plasticizer. The immobilization of the ionophore and surface characterization studies revealed that the performance of CMCR-immobilized PVC was equivalent to that of mobile ionophores in supported liquid membranes (SLMs). The strengths of the ion-ionophore (CMCR-Ti(OH)(OH2)52+) interactions and the role of ionophores on membranes were studied via UV-Vis, Fourier transform infrared spectroscopy (FT–IR), scanning electron microscopy (SEM) and and X-ray diffraction (XRD).

The complexation reactions between the macrocyclic ionophore, p-isopropylcalix[6]arene and Cs+ cation were studied in dimethylsulfoxide-acetonitrile (DMSO-AN) binary non-aqueous solvents at different temperatures using a conductometry method. The conductance data show that the stoichiometry of the (p-isopropylcalix[6]-arene·Cs)+ complex in all binary mixed solvents is 1:1. The stability of the complexes is affected by the composition of the binary solvent media and a non-linear behavior was observed for changes of log K(f) of the complex versus the composition of the binary mixed solvents. The thermodynamic parameters (DH°(c) and DS°(c)) for formation of (p-isopropyl-calix[6]arene·Cs)+ complex were obtained from temperature dependence of the stability constant and the obtained results show that the (p-isopropylcalix[6]arene·Cs)+ complex is enthalpy destabilized, but entropy stabilized, and the values of the mentioned parameters are affected strongly by the nature and composition of the binary mixed solvents.

The equilibrium constants and thermodynamic parameters for complexation process between titanium (III) cation and meso-octamethylcalix[4]pyrrole were determined by conductivity measurements in acetonitrile–ethanol (AN–EtOH) binary mixture at different temperatures. The conductance data show that the stoichiometry of the (meso-octamethylcalix[4]pyrrole.[Ti(OH)-(H2O)5])2+ complex in all binary mixed solvents is 1:1[I:M]. The stability of the formed complex is sensitive to the solvent composition and a non-linear behavior was observed for changes of log Kf of this complex versus the composition of the binary mixed solvents. The values of thermodynamic parameters (Hc and Sc) for formation of (meso-octamethylcalix[4]pyrrole.[Ti(OH)-(H2O)5])2+ complex were obtained from temperature dependence of the stability constant using van’t Hoff plots. The obtained results show that the formed complex is enthalpy destabilized, but entropy stabilized and a non-monotonic behavior was observed for variations of standard enthalpy and entropy changes versus the composition of the binary mixed solvents.

The equilibrium constants and thermodynamic parameters for complexation process between titanium (III) cation and meso-octamethylcalix[4]pyrrole were determined by conductivity measurements in acetonitrile–ethanol (AN–EtOH) binary mixture at different temperatures. The conductance data show that the stoichiometry of the (meso-octamethylcalix[4]pyrrole.[Ti(OH)-(H2O)5])2+ complex in all binary mixed solvents is 1:1[I:M]. The stability of the formed complex is sensitive to the solvent composition and a non-linear behavior was observed for changes of log Kf of this complex versus the composition of the binary mixed solvents. The values of thermodynamic parameters (Hc and Sc) for formation of (meso-octamethylcalix[4]pyrrole.[Ti(OH)-(H2O)5])2+ complex were obtained from temperature dependence of the stability constant using van’t Hoff plots. The obtained results show that the formed complex is enthalpy destabilized, but entropy stabilized and a non-monotonic behavior was observed for variations of standard enthalpy and entropy changes versus the composition of the binary mixed solvents.

A titanium (III) ion-selective membrane electrode sensor including a tris(2-pyridyl) methylamine ionophore, potassium tetrakis (4-chlorophenyl) borate additive, di-n-octyl phthalate plasticizer, poly(vinyl chloride) polymeric membrane and a solid body.

The complexation reactions between the macrocyclic ionophore, p-isopropylcalix[6]arene and Cs+ cation were studied in dimethylsulfoxide-acetonitrile (DMSO-AN) binary non-aqueous solvents at different temperatures using a conductometry method. The conductance data show that the stoichiometry of the (p-isopropylcalix[6]-arene·Cs)+ complex in all binary mixed solvents is 1:1. The stability of the complexes is affected by the composition of the binary solvent media and a non-linear behavior was observed for changes of log K(f) of the complex versus the composition of the binary mixed solvents. The thermodynamic parameters (DH°(c) and DS°(c)) for formation of (p-isopropyl-calix[6]arene·Cs)+ complex were obtained from temperature dependence of the stability constant and the obtained results show that the (p-isopropylcalix[6]arene·Cs)+ complex is enthalpy destabilized, but entropy stabilized, and the values of the mentioned parameters are affected strongly by the nature and composition of the binary mixed solvents.

The equilibrium constants and thermodynamic parameters for complexation process between titanium (III) cation and meso-octamethylcalix[4]pyrrole were determined by conductivity measurements in acetonitrile–ethanol (AN–EtOH) binary mixture at different temperatures. The conductance data show that the stoichiometry of the (meso-octamethylcalix[4]pyrrole.[Ti(OH)-(H2O)5])2+ complex in all binary mixed solvents is 1:1[I:M]. The stability of the formed complex is sensitive to the solvent composition and a non-linear behavior was observed for changes of log Kf of this complex versus the composition of the binary mixed solvents. The values of thermodynamic parameters (Hc and Sc) for formation of (meso-octamethylcalix[4]pyrrole.[Ti(OH)-(H2O)5])2+ complex were obtained from temperature dependence of the stability constant using van’t Hoff plots. The obtained results show that the formed complex is enthalpy destabilized, but entropy stabilized and a non-monotonic behavior was observed for variations of standard enthalpy and entropy changes versus the composition of the binary mixed solvents.

The equilibrium constants and thermodynamic parameters for complexation process between titanium (III) cation and meso-octamethylcalix[4]pyrrole were determined by conductivity measurements in acetonitrile–ethanol (AN–EtOH) binary mixture at different temperatures. The conductance data show that the stoichiometry of the (meso-octamethylcalix[4]pyrrole.[Ti(OH)-(H2O)5])2+ complex in all binary mixed solvents is 1:1[I:M]. The stability of the formed complex is sensitive to the solvent composition and a non-linear behavior was observed for changes of log Kf of this complex versus the composition of the binary mixed solvents. The values of thermodynamic parameters (Hc and Sc) for formation of (meso-octamethylcalix[4]pyrrole.[Ti(OH)-(H2O)5])2+ complex were obtained from temperature dependence of the stability constant using van’t Hoff plots. The obtained results show that the formed complex is enthalpy destabilized, but entropy stabilized and a non-monotonic behavior was observed for variations of standard enthalpy and entropy changes versus the composition of the binary mixed solvents.

Currently, despite of many developments in the field of ion selective electrodes (ISEs), it continues to evolve. The introduction of low detection limit ISEs may open a new opportunity to determine trace target ions. Improvements of detection limits, selectivities, understanding the response mechanism and developing new membrane materials are constantly being reported in the literatures. Moreover, the development of ISEs used in hospital and industrial setting as well as in clinical, environmental and physiological research has been opened new horizons in front of us. This research is focused on the fabrication of new PVC-membrane sensors based on tris(2pyridyl) methylamine, tpm and c-methylcalix[4]resorcinarene, CMCR as an cationic ionophores for detection of titanium (III) cation, and also N,N′Bis(salicylidene) ethylenediamino cobalt(II),Co(SALEN) as an anionic ionophore for determining the chromate (II) anion. The complex reactions of Co(SALEN) with chromate (II) anion, tpm and CMCR with titanium (III) cation in water (H2O), acetonitrile (AN) and their binary mixture solutions at different temperatures by using the conductometric method, are investigated. The characterization and evalution of materials are described. In addition, a variety of analytical methods, including UV-Vis spectroscopy, FT-IR spectroscopy, Scanning Electron Microscopy (SEM), are used to study these processes. Later on, the application and validation of proposed ISEs with the potentiometric titration, atomic absorption spectrometry (AAs) and inductively coupled plasma atomic emission spectrometry (ICP-AES) are studied. Based on conductometric measurement results, the stoichiometry of complex formation for all the cases of ion-ionophore is 1:1. Furthermore, the average of stability constant (logKf) obtained for tpm-Ti(OH)(OH2)52+, CMCRTi(OH)(OH2)52+ and Co(SALEN)-CrO42- complexes at 25⁰C are 2.70, 3.13 and 3.02, respectively. Therefore, the mentioned ionophores can be used as sensing elements

A titanium (III) ion-selective membrane electrode sensor including a tris(2-pyridyl) methylamine ionophore, potassium tetrakis (4-chlorophenyl) borate additive, di-n-octyl phthalate plasticizer, poly(vinyl chloride) polymeric membrane and a solid body.

Currently, despite of many developments in the field of ion selective electrodes (ISEs), it continues to evolve. The introduction of low detection limit ISEs may open a new opportunity to determine trace target ions. Improvements of detection limits, selectivities, understanding the response mechanism and developing new membrane materials are constantly being reported in the literatures. Moreover, the development of ISEs used in hospital and industrial setting as well as in clinical, environmental and physiological research has been opened new horizons in front of us. This research is focused on the fabrication of new PVC-membrane sensors based on tris(2pyridyl) methylamine, tpm and c-methylcalix[4]resorcinarene, CMCR as an cationic ionophores for detection of titanium (III) cation, and also N,N′Bis(salicylidene) ethylenediamino cobalt(II),Co(SALEN) as an anionic ionophore for determining the chromate (II) anion. The complex reactions of Co(SALEN) with chromate (II) anion, tpm and CMCR with titanium (III) cation in water (H2O), acetonitrile (AN) and their binary mixture solutions at different temperatures by using the conductometric method, are investigated. The characterization and evalution of materials are described. In addition, a variety of analytical methods, including UV-Vis spectroscopy, FT-IR spectroscopy, Scanning Electron Microscopy (SEM), are used to study these processes. Later on, the application and validation of proposed ISEs with the potentiometric titration, atomic absorption spectrometry (AAs) and inductively coupled plasma atomic emission spectrometry (ICP-AES) are studied. Based on conductometric measurement results, the stoichiometry of complex formation for all the cases of ion-ionophore is 1:1. Furthermore, the average of stability constant (logKf) obtained for tpm-Ti(OH)(OH2)52+, CMCRTi(OH)(OH2)52+ and Co(SALEN)-CrO42- complexes at 25⁰C are 2.70, 3.13 and 3.02, respectively. Therefore, the mentioned ionophores can be used as sensing elements

In this work a membrane was prepared by use of N,N′Bis(salicylidene) ethylenediamino cobalt(II) hydrate (Co(SALEN)2) as an ion carrier, polyvinylchloride (PVC) as matrix, and 2-nitrophenyl octyl ether (2NPOE) as a plasticizer for an ion-selective electrode used in the measurement of CrO42-anions in solution. The amounts of (Co(SALEN)2) and PVC were optimized in the preparation of the membrane. The response of the electrode was Nernstian within the concentration range 1.0 × 10-6 to 1.0 × 10-1 M. This sensor displays a drift in Nernstian response for this anion changes with the amount of ionophore and PVC. The effects of various parameters such as pH, different anion interferences, the amounts of ionophore and PVC and time on response of the coated ion-selective electrode were investigated. The response of the fabricated electrode at concentration range from 1.0× 10-6 to 1.0× 10-1 M is linear with a Nernstian slope of -28.33 mV.

In this work a membrane was prepared by use of N,N′Bis(salicylidene) ethylenediamino cobalt(II) hydrate (Co(SALEN)2) as an ion carrier, polyvinylchloride (PVC) as matrix, and 2-nitrophenyl octyl ether (2NPOE) as a plasticizer for an ion-selective electrode used in the measurement of CrO42-anions in solution. The amounts of (Co(SALEN)2) and PVC were optimized in the preparation of the membrane. The response of the electrode was Nernstian within the concentration range 1.0 × 10-6 to 1.0 × 10-1 M. This sensor displays a drift in Nernstian response for this anion changes with the amount of ionophore and PVC. The effects of various parameters such as pH, different anion interferences, the amounts of ionophore and PVC and time on response of the coated ion-selective electrode were investigated. The response of the fabricated electrode at concentration range from 1.0× 10-6 to 1.0× 10-1 M is linear with a Nernstian slope of -28.33 mV.