Voltammetric determination of isoproterenol using a 5-amino-2’,4’-dimethoxybiphenyl-2-ol modified carbon nanotube paste electrode

A new electrochemical sensor for determination of isoproterenol(IP) is described.The sensor is based on carbon paste electrode (CPE) modified with 5-amino-2’,4’-dimethoxybiphenyl-2-ol(5ADMB) and takes the advantages of carbon nanotubes(CNTs). Under the optimum pH of 7.0,the oxidation of IP occurs at a potential about 210 mV less positive than that of the unmodified CPE. The oxidation currents increased linearly with two concentration intervals of IP,one is 0.09 to 20.0 |xmol/L and,the other is 20.0 to 400.0μmol/L.The detection limit(3σ) obtained by square wave voltammetry(SWV) was 39.0 nmol/L.The practical application of the modified electrode was demonstrated by determining IP in IP ampoule,urine and human blood serum samples.     

Using Pd-salen complex as an efficient catalyst for the copper-and solvent-free coupling of acyl chlorides with terminal alkynes under aerobic conditions

<正>The palladium-salen complex palladium(Ⅱ) N,N'-bis{[5-(triphenylphosphonium)-methyl]salicylidene}-1,2-ethanediamine chloride was found to be a highly active catalyst for the copper- and solvent-free coupling reaction of terminal alkynes with different acyl chlorides in the presence of triethylamine as base,giving excellent ynones under aerobic conditions.     

Synthesis of organosoluble polyamides with bulky triaryl imidazole pendent group

New unsymmetrical diamine monomer containing triaryl imidazole pendent group,4-[4-(4,5-diphenyl-1H-imidazol-2-yl)phenoxy] -1,3-benzenediamine,was synthesized via aromatic substitution reaction of 1-chloro-2,4-dinitrobenzene with 4-(4,5- diphenyl-1H-imidazol-2-yl)phenol,followed by palladium-catalyzed hydrazine reduction.This new monomer was further confirmed by FT-IR,~1H NMR and ~(13)C NMR.Novel polyamides having pendant triaryl imidazole group were prepared by the phosphorylation polycondensation of fou...     

Cs_xH_(3-x)PW_(12)O_(40) heteropoly salts catalyzed quinoline synthesis via Friedl(a|¨)nder reaction

Various type of cesium partially substituted phosphotungstate,Cs_xH_3-xPW₁₂O₄₀（x = 1.0,2.0 and 2.5）,were synthesized and their catalytic activities were investigated in the synthesis of quinoline.It was shown that catalytic activities of these catalysts correlated to surface acidity and total number of acidic sites.Finally,a series of quinoline derivatives were synthesized with Cs_2.5H_0.5PW₁₂O₄₀ via the Friedlander reaction in high to excellent yields and the plausible mechanism was proposed.Simple experiment,catalyst reusability,short reaction time and preclusion of toxic solvent are the advantages of this method.     

A thermodynamic investigation on the binding of mercury ion with myelin basic protein at different temperatures

A thermodynamic study on the interaction of myelin basic protein with mercury ion was studied by using isothermal titration calonmetry,ITC,at 300.15,310.15 and 320.15 K in Tris buffer solution at pH 7.The enthalpies of MBP + Hg²⁺ interaction are reported and analysed in terms of the extended solvation model.It was found that MBP has two identical and non-cooperative binding sites for Hg²⁺ ions.The intrinsic dissociation equilibrium constants are 99.904,112.968 and 126.724μmol/L,and the molar enthalpy of binding are -11.634,-10.768 and -10.117kJ mol^-1 at 300.15,310.15 and 320.15 K,respectively.     

Ligandless C‐C bond formation via Suzuki–Miyaura reaction in micelles or water–ethanol solution using PdPtZn and PdZn nanoparticle thin films

PdPtZn and PdZn nanoparticle (NP) thin films were synthesized by the reduction of [PdCl₂(cod)], [PtCl₂(cod)] (cod = cis,cis‐1,5‐cyclooctadiene) and [Zn(acac)₂] (acac = acetylacetonate) complexes at an oil–water interface. The structure and morphology of the as‐prepared NPs were characterized with X‐ray diffraction, transmission electron microscopy and energy dispersive analysis of X‐rays. Catalytic activity of the prepared NPs was investigated in the Suzuki–Miyaura cross‐coupling reaction in H₂O–EtOH and various micellar media systems such as cetyltrimethylammonium bromide (cationic surfactant), sodium dodecylsulfate (anionic surfactant) and Pluronic P123 (non‐ionic surfactant). PdPtZn and PdZn thin films exhibited higher catalytic activity compared to Pd thin film in the Suzuki–Miyaura coupling reaction due to the appropriate interaction between palladium, platinum and zinc metals. Copyright © 2015 John Wiley & Sons, Ltd.     

Electrical,structural and thermal properties of new conductive blends (PANICG) based on polyaniline and cashew gum for organic electronic

Journal of Thermal Analysis and Calorimetry - The application of cashew gum, in particular the one which is abundant in northeastern Brazil, remains limited to the foods and pharmaceutics industry....     

Bioconjugation of Interferon-alpha Molecules to Lysine-Capped Gold Nanoparticles for Further Drug Delivery Applications

Gold nanoparticles are potentially very attractive components for therapeutic delivery since they can be synthesized with any diameter from 1 to 200 nm to carry a payload of therapeutic molecules into a cell without triggering an immune response. Gold nanoparticles must undergo surface transformations before coupling to therapeutic molecules to become eligible for this purpose. It is now more understood that amine groups can bind to gold nanoparticles strongly, which has enabled surface modification of gold nanoparticles with amino acid lysine through its amine group. These lysine capped gold nanoparticles can further be coupled to therapeutic molecules for delivery purposes. In this study gold nanoparticles were first synthesized and capped with lysine molecules. TEM and FTIR measurements demonstrated the synthesis of lysine-capped gold nanoparticles with an average diameter of 10 nanometers. Interferon alpha molecules-one of the most important therapeutic protein were then chemically bound to lysine-capped gold nanoparticles through a two-step process of diimide-activated amidation. The conjugation of interferon molecules to lysine capped gold nanoparticles was carried out via the reaction between the free amine group of lysine and carboxyl groups of interferon using N-ethyl-N′-13-dimethyl-aminopropyl (EDAC) as a coupling agent. The process of conjugation has also been studied by transmission electron microscopy.     

Boron–π interactions in two 3-(dihydroxyboryl)anilinium salts analyzed by crystallographic studies and supported by the noncovalent interactions (NCI) index theoretical approach

In the title compounds, 3-(dihydroxyboryl)anilinium bisulfate monohydrate, C₆H₉BNO₂⁺·HSO₄⁻·H₂O ( I ), and 3-(dihydroxyboryl)anilinium methyl sulfate, C₆H₉BNO₂⁺·CH₃SO₄⁻ ( II ), the almost planar boronic acid molecules are linked by pairs of O—H…O hydrogen bonds, forming centrosymmetric motifs that can be described by the graph-set R₂²(8) motif. In both crystals, the B(OH)₂ group acquires a syn–anti conformation (with respect to the H atoms). The presence of the hydrogen-bonding functional groups B(OH)₂, NH₃⁺, HSO₄⁻, CH₃SO₄⁻ and H₂O generates three-dimensional hydrogen-bonded networks, in which the bisulfate (HSO₄⁻) and methyl sulfate (CH₃SO₄⁻) counter-ions act as the central building blocks within the crystal structures. Furthermore, in both structures, the packing is stabilized by weak boron–π interactions, as shown by noncovalent interactions (NCI) index calculations.     

Applications of Non-precious Transition Metal Oxide Nanoparticles in Electrochemistry

Non-precious transition metal oxide nanomaterials offer numerous opportunities for various cost-effective electrochemical applications. This review article features the design and advancement of such nanomaterials with unique features applied for the fabrication of electrochemical devices. Also, it discusses various new syntheses of transition metal oxide nanoparticles (TMO NPs) via multiple chemicophysical and biological procedures. Further, the novel appliances of the TMO NPs with varying sizes and morphologies are appraised. The advantages and challenges of a number of investigations on the TMO NPs towards electrochemical applications are addressed with their standpoint of cost-effectiveness, applicability, and the efficiency of the introduced nanostructures for the industrial applications.