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NESP (novel erythropoiesis-stimulating protein) is a recently approved hyperglycosylated analogue of human erythropoietin (EPO) with a long-lasting effect. In this work, the capillary electrophoresis (CE) methodology proposed by the European Pharmacopoeia for the separation of EPO glycoforms has been modified for the separation of NESP glycoforms. Optimization of pH of the separation electrolyte has been fundamental in order to achieve baseline resolution of seven peaks corresponding to NESP glycoforms. Intact NESP has also been characterized by matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS). An accurate approximation to an average molecular mass of the NESP molecule has been obtained, taking into account the strong influence of laser intensity upon the MALDI-TOF mass spectra found. 相似文献
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Experimental liquid–liquid phase diagrams are presented for the multicomponent systems isooctane–benzene–(80 mass% methanol + 20 mass% water)–5 mass% isobutyl alcohol (2-methyl-1-propanol) and isooctane–benzene–(80 mass% methanol + 20 mass% water)–15 mass% isobutyl alcohol, at 298.15 K. The density and interfacial tension of conjugate phases of concentration located in the isothermal binodal have been determined at 298.15 K for the partially miscible systems: isooctane–benzene–methanol, isooctane–benzene–(80 mass% methanol + 20 mass% water), isooctane–benzene–(80 mass% methanol + 20 mass% water)–5 mass% isobutyl alcohol, and isooctane–benzene–(80 mass% methanol + 20 mass% water)–15 mass% isobutyl alcohol. The experimental tie-line data define the binodal or coexistence curve of the two studied multicomponent systems and depending on the initial isobutyl alcohol concentration the liquid–liquid phase diagram is either of type II, with low alcohol concentration, or type I, with high concentration of alcohol, which is a clear indication that the solubility of the partially miscible systems is greatly enhanced via the co-solvency phenomenon. It is observed that both the density of each conjugate phase and the interfacial tension of each tie-line are valuable indicators of the degree of solubility of the multicomponent systems. Furthermore the experimental tie-lines data were correlated with the NRTL and UNIQUAC solution models with satisfactory quantitative results. 相似文献
54.
Anthony D. Patrick Pamela Williams Estela Blaisten-Barojas 《Journal of Molecular Structure》2007,824(1-3):39-47
Small carbon clusters C, C2 and C3 metallized with beryllium were studied by first principles within the hybrid density functional approach with generalized gradient correction. Cluster isomer structures for the ground state and several excited states where systematically calculated for CxBey with x = 1–3 and y = 1–4 including the vibrational analysis of all states. Ionization potentials and electron affinities are calculated for the ground state cluster isomers. The thermal stability of the ground state isomers was verified within the harmonic approximation of the Helmholtz free energy up to temperatures of about 1000 K. Within the family of clusters studied, C2Be3 undergoes a solid-like structural transition at about 260 K changing from a planar structure at low temperatures to a linear isomer at high temperatures. 相似文献
55.
Eliraldrin Amorin Sousa Alex Otávio Sanches José Luiz Vilches Michael Jones da Silva Fernando Rogério de Paula Colleen Marie McMahan José Antonio Malmonge 《先进技术聚合物》2024,35(2):e6306
Natural rubber (NR) microfibers were obtained from NR/chloroform solutions with or without vulcanization agents, by a solution blow spinning (SBS) technique. The microfibers showed a ribbon-like morphology with average widths ranging from 15 to 45 μm, depending on the processing conditions. Concentrations of 3%, 4%, and 5% (wt/vol) of NR/chloroform were compared; at 4% wt/vol the spinning process was most stable, and fiber width was the most homogeneous. Microfibrous NR membranes incorporating vulcanizing agents were treated at temperatures of 70, 80, and 90°C for 1, 2, 3, and 4 h. Membrane tensile strength and elongation at break varied with temperature and treatment time. The best result was found with the sample treated at 90°C for 3 h. In this case, the tensile strength and elongation at break was (4.9 ± 0.8) MPa and (867 ± 18) % which is about 310% and 330% higher than the values found for the same sample without the incorporation of vulcanizing agents. This expressive increase was attributed to the vulcanization of the rubber, which also provided a shift to a higher value of the glass transition temperature. Overall properties of the blow-spun films, especially the high elasticity-contraction, suggest they are attractive candidates for use in robotics, and biobased electronics including wearable sensors. 相似文献
56.
Heron Vrubel Manfredo Hrner Estela dos Reis Crespan Shirley Nakagaki Fbio S. Nunes 《无机化学与普通化学杂志》2008,634(11):1839-1841
Hydrogen peroxide reacts with [MoO2Cl2(dmso)2] to produce orange crystals of the title complex, [MoO(O2)Cl2(dmso)2]. The structure is orthorhombic with distorted pentagonal bipyramidal geometry around the molybdenum ion. A short O‐O bond length suggested the presence of a superoxide, but electron paramagnetic resonance measurements definitely supported the peroxo structure. 相似文献
57.
Bienfait M Zeppenfeld P Dupont-Pavlovsky N Palmari JP Johnson MR Wilson T DePies M Vilches OE 《Physical review letters》2003,91(3):035503
We report experimental studies of the adsorption characteristics and structure of both 36Ar and 40Ar on single-wall carbon nanotube bundles. The structural studies make use of the large difference in coherent neutron scattering cross section for the two Ar isotopes to explore the influence of the adsorbate on the nanotube lattice parameter. We observe no dilation of the nanotube lattice with 40Ar, and explain the apparent expansion of this lattice upon 36Ar adsorption by the location of the adsorbed Ar atoms on the outer bundle surface. 相似文献
58.
Cover Picture: Sulfoxide‐Directed Metal‐Free ortho‐Propargylation of Aromatics and Heteroaromatics (Chem. Eur. J. 20/2015)
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