A Bis‐Oxime Derivative of Diaza‐18‐Crown‐6 as an Ionophore for Silver Ion

A new pendant‐arm derivative of diaza‐18‐crown‐6, containing two oxime donor groups, has been synthesized and incorporated into a polyvinyl chloride (PVC) membrane ion‐selective electrode. The electrode shows selectivity for Ag⁺ ion, with a near Nernstian response. Pb²⁺, Cu²⁺, Hg²⁺, and Tl⁺ are major interfering ions, with Cd²⁺ having minor interference. The electrode shows no potentiometric response for the ions Mg²⁺, Al³⁺, K⁺, Ca²⁺, Ni²⁺, Fe³⁺, and La³⁺, and is responsive to H⁺ at pH<6.     

A new phenothiazine-based fluorescence sensor for imaging Hg2+ in living cells

A new phenothiazine-based sensor PHE-Ad for monitoring Hg²⁺ has been designed and synthesized based on the intramolecular charge transfer (ICT) mechanism. The probes were characterized by FTIR, ¹H NMR, and HRMS, and their optical properties were detected by UV and FL. It's showed the probes detection of Hg²⁺ compared to other metal ions (Mg²⁺, Cu²⁺, Hg²⁺, Ag⁺, Co²⁺, Cr³⁺, Al³⁺, Ni²⁺, Zn²⁺, Ca²⁺, Fe³⁺, Fe²⁺, K⁺, Na⁺, and Cd²⁺) based on the test results. Besides, the detection limits were determined to be 2.12 × 10⁻⁸ M through the standard curve plot. In addition, sensor PHE-Ad shows high selectivity and sensitivity for Hg²⁺ with a fast response in a suitable pH range. Furthermore, taking into account its good “turn-on” fluorescent sensing behavior and low cell cytotoxicity, PHE-Ad was successfully applied to detect and image Hg²⁺ in real water samples and living cells, which shows great potentials for application in environmental and biological systems.     

Synthesis and acid-base and complex-forming properties of 1,4,7,10-tetrakis(dihydroxyphosphorylmethyl)-1,4,7,10-tetraazacyclododecane

Conclusions A new complexone, 1,4,7,10-tetrakis(dihydroxyphosphorylmethyl)-1,4,7,10-tetraazacyclododecane, has been synthesized and its acid-base and complex-forming properties have been studied. It shows a very high complexing capability and marked selectivity for cations of large ionic radius (Cd²⁺, Hg²⁺, Pb²⁺, La³⁺).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 844–849, April, 1984.     

Design and synthesis of two armed molecular receptor for recognition of Gd3+ metal ion and its computational study

New receptor P henylene‐ B is‐ M ethylfuran‐yl‐2‐ M ethyele A cetohydrazide ( PBMMA ) has been synthesized by condensation of hydrazide and 5‐methyl furfural. Synthesized receptor has been fully characterized by IR, ¹H NMR, ¹³C NMR, mass spectroscopic and thermo gravimetric analysis. The receptor PBMMA shows selective recognition potential towards Gd³⁺ ion when tested with several metal ions such as Na⁺, K⁺, Mg²⁺, Cu²⁺, Cd²⁺, Hg²⁺, Y³⁺, La³⁺, Eu³⁺, Sm³⁺, Gd³⁺, Re⁶⁺ and Th⁴⁺ ion as their sulfates by UV–visible and fluorescence spectroscopic studies. Binding nature of PBMMA with Gd³⁺ ion was further studied by mass spectroscopic and cyclic voltammetric studies. The stoichiometry of PBMMA‐ Gd³⁺ ion has been established, 1:1 by Benesi‐Hildebrand plot method and method of continuous variation (Job's plot) with association affinity K = 6.491 × 10⁴ M^?1. In addition to these, molecular docking, molecular dynamic stimulation and binding energy of complex; through Density Function theory ?595.66 kcal/mol has also indication of strong binding. The electron transfer energy of Higher occupied molecular orbital (HOMO) to Lower unoccupied molecular orbital (LUMO) is about 4.186 eV and 295 nm for PBMMA‐Gd³⁺ Complex.     

Dual-mode recognition of transition metal ions by bis-triazoles chained pyrenes

Fluorescent chemosensors 7−10, with variable methylene chain length as spacers between the two triazole methyl ether units, have been synthesized under ‘Click’ condition, where the bistriazoles are used as the metal ion binding sites and the pyrenes as the fluorophores. Compound 10, having the longest methylene chain among 7−10, shows monomer and excimer fluorescence quenching in acetonitrile toward Ni²⁺, Pb²⁺, Cu²⁺, Hg²⁺, and Cr³⁺ ions, however, it shows an enhanced monomer but a decreased excimer emission when complexed with Cd²⁺ and Zn²⁺ ions.     

Thiazole sulfonamide based ratiometric fluorescent chemosensor with a large spectral shift for zinc sensing

A new thiazole sulfonamide (TTP, 1) based Zn²⁺ selective intrinsic chemosensor has been synthesized and investigated. The chemosensor shows a selective fluorescence enhancement (3.0 fold) with Zn²⁺ over biologically relevant cations (Ca²⁺, Mg²⁺, Na⁺, and K⁺) and biologically non-relevant cations (Cd²⁺) in an aqueous ethanol system. It produces an increase in the quantum yield and a longer emission wavelength shift (64 nm) on Zn²⁺ binding with the potential of a ratiometric assay.     

One stone kills four birds: a novel diazaperinone 12H-pyrazino[2′,3′:3,4]pyrrolo[1,2-a]perimidin-12-one recognizes four different metal ions

A novel diazaperinone 12H-pyrazino[2′,3′:3,4]pyrrolo[1,2-a]perimidin-12-one has been successfully synthesized through a one-step condensation. Single crystal X-ray analysis shows that the product is of planar structure with strong π?π interactions and H-bonding. Interestingly, the 12H-pyrazino[2′,3′:3,4]pyrrolo[1,2-a]perimidin-12-one can recognize three different metal cations Cu²⁺, Ag⁺ and Hg²⁺ via naked eye visualization, and shows turn-on fluorescence for Fe³⁺ and Ag⁺ among the 22 metal cations.     

Design and synthesis of a new fluorescent tripod for chemosensor applications

A new yellow-green fluorescent tripod based 1,8-naphthalimide has been synthesized and characterised. Its photophysical properties have been investigated in organic solvents of different polarity. The effect that the metal ions (Cd²⁺, Co²⁺, Zn²⁺, Mn²⁺, Mg²⁺, Ni²⁺, Pb²⁺, Cu²⁺, Ba²⁺, Fe³⁺ and Ag⁺) produce upon the fluorescent intensity of acetonitrile solutions of the tripod has been discussed viewing its potential applications as a detector for metal cations. The influence of protons on the fluorescence intensity of the tripod in DMF and methanol–water (1:4 v/v) solutions has also been investigated.     

Etude des Proprietes de Retention du Filtre Inorganique PbS en vue de ses Applications en Radiochimie Analytique

The fixation behavior of PbS specially prepared for analytical purposes has been studied using batch equilibration technique and chromatographic columns. This inorganic adsorbant shows a high and specific fixation capacity for ions such as Cu²⁺, Hg²⁺, Br⁻ SeO ₄ ²⁻ . An interpretation of the fixation mechanism is proposed.      

Selective extraction of toxic heavy metals and biological activity studies using pyrimidylthioamide functionalised calix[4]arene

The current study comprises synthesis of pyrimidylthioamide derivatized calix[4]arene (5), and its comparative liquid–liquid extraction properties with the compound 4 towards the selected transition metal ions (Cu²⁺, Co²⁺, Ni²⁺, Pb²⁺, Hg²⁺ and Cd²⁺) were investigated. Experimental results revealed that the compound 5 shows better efficiency and affinity for Pb²⁺ and Hg²⁺ ions as compared to compound 4. The antibacterial and antifungal effects of compound 5 were also investigated on various bacteria and fungi. It has been observed that compound 5 has some effects against Salmonella typhimurium NRRLB 4420, Bacillus cereus ATCC 11778, Staphylococcus aureus NRRL B767 and Bacillus subtilis NRS 744.     

A new Hg2+ fluorescent sensors based on 1,3-alternate thiacalix[4]arene (L) and the complex of [L+Hg2+] as turn-on sensor for cysteine

A new thiacalix[4]arene derivative in a 1,3-alternate conformation bearing four naphthalene groups through crown-3 chains has been synthesized, which exhibits high selectivity toward Hg²⁺ by forming a 1:2 complex, among other metal ions ( Na⁺, K⁺, Mg²⁺, Ba²⁺, Ca²⁺, Sr²⁺, Cs⁺, Mn²⁺, Fe²⁺, Cd²⁺, Co²⁺, Ni²⁺, Cu²⁺, Li⁺, and Zn²⁺) with a low detection limit (3.30×10^?7 M). The metal ion-binding properties were studied by fluorescence, AFM, and ¹H NMR spectroscopy. The in situ prepared [Hg²⁺+L] complex shows well recognition ability for cysteine with a low detection limit (2.23×10^?7 M) through fluorescence turning on. The mechanism of fluorescence turning on is the host L releasing from [L+Hg²⁺] for [Cys+Hg²⁺] complex formed. Thus the paper reports secondary-sensor design: Hg²⁺ as a first sensor for [L+Hg²⁺] form, cysteine as a second sensor for Hg²⁺ releasing from the [L+Hg²⁺] complex after cysteine adding in.     

1-(d-Glucopyranosyl-2′-deoxy-2′-iminomethyl)-2-hydroxynaphthalene as chemo-sensor for Fe in aqueous HEPES buffer based on colour changes observable with the naked eye

A new glucose-based C2-derivatized colorimetric chemo-sensor (L₁) has been synthesized by a one-step condensation of glucosamine and 2-hydroxy-1-naphthaldehyde for the recognition of transition metal ions. Among the eleven metal ions studied, viz., Mg²⁺, Ca²⁺, Mn²⁺, Fe²⁺, Fe³⁺, Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺, Cd²⁺ and Hg²⁺, L₁ results in visual colour change only in the presence of Fe²⁺, Fe³⁺and Cu²⁺ in methanol. However, in an aqueous HEPES buffer (pH 7.2) it is only the Fe³⁺ that gives a distinct visual colour change even in the presence of other metal ions, up to a concentration of 280 ppb. The changes have been explained based on the complex formed, and the composition has been determined to be 2:1 between L₁ and Fe³⁺ based on Job’s plot as well as ESI MS. The structure of the proposed complex has been derived based on HF/6-31G calculations.     

Energy transfer phenomena in lead sulphate

It is shown that lead sulphate, PbSO₄, shows Pb²⁺ emission with a large Stokes shift. Energy transfer has been observed from the Pb²⁺ ions to several luminescent centres, viz., tungstate, molybdate, vanadate and rare earths. No transfer occurs to the Pr³⁺ ion.     

Synthesis and Structures of the Novel Biferrocenamine‐Based Receptor and its Voltammetric Responses to Transition Metal Ions

Reactions of formylferrocene and 1,2‐di‐(o‐aminophenoxy)ethane yield the novel bis(ferrocenyl) receptor (FcL). This compound has been characterized by IR, ¹H NMR and elemental analysis. In addition, the electrochemical behavior of FcL was investigated in detail in 0.1 M tetra‐n‐butylammonium perchlorate (TBAP) + CH₃CN by cyclic voltammetry (CV) and chronoamperometry. Its co‐ordination properties with metal ions in acetonitrile were also studied. The FcL shows a two‐wave behavior for H⁺, Cu²⁺, Zn²⁺ and Ni²⁺, but was unresponsive to Mg²⁺ and Ca²⁺. The maximum oxidation peak shift of about 250 mV was found for FcL in the presence of Cu²⁺, Zn²⁺ or Ni²⁺.     

Synthesis and characterization of zirconium(IV) 4-amino, 3-hydroxy naphthalene sulfonate ion exchanger: Quantitative separation of mercury from numerous metal ions

Zirconium (IV) 4-amino, 3-hydroxy naphthalene sulfonate ion-exchanger has been synthesized by mixing equimolar solutions of zirconium oxychloride and ammonium hydroxide in molar ratio 1:1.66 to get a gelatinous material. To this were added varying amounts of 4-amino, 3-hydroxynaphthalene sulphonic acid (ANSA) with constant stiring in order to ensure a complete adsorption of organic molecules to the surface of the gel. The ion exchange material shows a dual character possessing both cation and anion exchange capacities. The former is attributed to the dissociation of strong sulphonic groups from ANSA and acidic sites of hydrous oxide gel, the later one is due to the formation of a positive charge on the nitrogen atom ; in addition, the material may have a sorption capacity. A preliminary investigation to characterize the material has been carried out which includes IR, TGA, DTA and X-ray diffraction. On the basis of distribution coefficients the separation of Hg⁺² from Zn²⁺, Al²⁺, Ni²⁺, Ce⁴⁺, Mg²⁺, Pb²⁺, Mn²⁺, Cu²⁺, has been achieved. The decreasing sequence of Kd values for different anionic species are found to be PO₄³⁻ > Fe (CN)₆³⁻ > MnO₄⁻ > VO₃⁻ > AsO₄³⁻ > C₂O₄²⁻ and for halides Cl⁻ > Br⁻ > I⁻.     

Analytical reactions of substituted cyanoferrates : I. Na3[Fe(CN)5(NH3)]

The reagent pentacyanoamminoferrate (PCAF) in its aqueous reactions with some common cations and anions produces colored species in solution. It has been observed that the reactions of Fe³⁺, Fe²⁺, Co²⁺, VO²⁺, Mo⁶⁺, S₂O₃²⁻, and NO₂⁻ are sensitive enough to permit their colorimetric determinations. In addition, the reagent has been found useful in the simultaneous trace analysis of Fe³⁺ and VO²⁺ present in the same solution.A comparative study has been made of the reactions of PCAF and the other unsubstituted cyanoferrates(II) and (III).     

Ground state Pi-electron triplet molecules of potential use in the synthesis of organic ferromagnets

2,3,6,7,10,11-Tris(N,N′-diethylethylenediamino)triphenylene (HET) has been synthesized by a route involving hexabromination of triphenylene, reaction with ethylenediamine, hexa-acetylation, and reduction with diborane. Cyclic voltammetry shows that HET can be reversibly oxidized to a mono-cation HET⁺, a dication HET²⁺, a trication HET³⁺, and a tetraction HET⁴⁺. Beyond that the oxidation is irreversible. The dication HET²⁺ is a ground-state triplet species. This fact, and the low oxidation potential required to produce it, make it of interest in testing proposed mechanism for preparing organic ferromagnetic materials.     

Carbon Nanotubes/Ionophore Modified Electrode for Anodic Stripping Determination of Lead

Bifunctional combination of carbon nanotubes and ionophore is introduced for anodic stripping analysis of lead (Pb²⁺). Carbon nanotubes are employed to improve the detection sensitivity due to their excellent electrical conductivity and strong adsorption ability. An ionophore is utilized for its excellent selectivity toward Pb²⁺. The proposed carbon nanotubes/ionophore modified electrode shows improved sensitivity and selectivity for Pb²⁺. Low detection limit (1 nM), wide linear range (5 nM–8 µM) and excellent selectivity over other metal ions (Cd²⁺, Cu²⁺, and Hg²⁺) was obtained. The practical application has been carried out for determination of Pb²⁺ in real water samples.     

Quantitative Separation of Hg(11) From Several Metal Ions on Zr(IV) Antimonate Papers

Abstract

The chromatographic behaviour of 32 metal ions has been studied on paper Impregnated with Zirconium(IV) antimonate in aqueous HCI and mixed solvent system containing dimethyisul phoxide and dioxane. Several Important binary and ternary separations have been achieved. Quantitative separation of Hg(ll) from Ni²⁺, Pb²⁺, Pd²⁺, Ru³⁺, Rh³⁺, Bi³⁺, Co²⁺, Cd²⁺ and Gd³⁺ is described.     

Cation analysis by thin-layer chromatography and reflectance spectroscopy : Part I. The rapid identificaiion of cations resolved on thin-layer plates

A rapid method has been devised whereby 14 cations — Al³⁺, Bi³⁺, Cd²⁺, Cr³⁺, Co²⁺, Cu²⁺, Fe³⁺, Pb²⁺, Mn²⁺, Hg²⁺, Ni²⁺, Ag⁺, Sn²⁺ and Zn²⁺ —. can be separated on one-dimensional, cellulose thin-layer plates and then identified by means of their reflectance spectra The procedure requires micro-amounts of sample and only one spray reagent.