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1.
Antonio R. Montoro Bustos Marta Garcia-Cortes Hector González-Iglesias Jorge Ruiz Encinar José M. Costa-Fernández Miguel Coca-Prados Alfredo Sanz-Medel 《Analytica chimica acta》2015
A generic strategy based on the use of CdSe/ZnS Quantum Dots (QDs) as elemental labels for protein quantification, using immunoassays with elemental mass spectrometry (ICP-MS), detection is presented. In this strategy, streptavidin modified QDs (QDs-SA) are bioconjugated to a biotinylated secondary antibody (b-Ab2). After a multi-technique characterization of the synthesized generic platform (QDs-SA-b-Ab2) it was applied to the sequential quantification of five proteins (transferrin, complement C3, apolipoprotein A1, transthyretin and apolipoprotein A4) at different concentration levels in human serum samples. It is shown how this generic strategy does only require the appropriate unlabeled primary antibody for each protein to be detected. Therefore, it introduces a way out to the need for the cumbersome and specific bioconjugation of the QDs to the corresponding specific recognition antibody for every target analyte (protein). Results obtained were validated with those obtained using UV–vis spectrophotometry and commercial ELISA Kits. 相似文献
2.
Alfredo Paio Sylvie GehanneElena Grandini Gianna ReginatoPierfausto Seneci 《Tetrahedron letters》2003,44(9):1867-1870
A rapid and quantitative method for monitoring the efficiency of coupling of amino compounds to polystyrene resin through a carbamate linker has been developed. para-Nitrophenyl carbonate activating group has been shown to release a valuable chromophore for quantitatively monitoring the progress and the yield of the reaction. 相似文献
3.
First order necessary conditions and duality results for general inexact nonlinear programming problems formulated in nonreflexive
spaces are obtained. The Dubovitskii–Milyutin approach is the main tool used. Particular cases of linear and convex programs
are also analyzed and some comments about a comparison of the obtained results with those existing in the literature are given. 相似文献
4.
We present a modification of the Cyclic Subgradient Projection (CSP) method by Censor and Lent, which solves the convex feasibility problem in a finite number of steps when a Slater type condition holds, while preserving its row-action properties. A linear rate of convergence for the CSP method is established assuming the same hypothesis.Research partially supported by CNPq, under Grant No. 301699/81. 相似文献
5.
Let G be a non-compact connected semisimple Lie group with finite center and let GK denote the centralizer of a maximal compact subgroup K of G inG, the universal enveloping algebra over of the Lie algebra of G. In [4] Lepowsky defines an injective anti-homo morphism P:G
KK
MA, where M is the centralizer in K of a Cartan subalgebraa of the symmetric pair (G,K),K andA are the universal enveloping algebras over corresponding to K anda, respectively, andK
M is the centralizer of M inK. The subalgebra P(G
K) ofK
MA has considerable significance in the infinite dimensional representation theory of G. In this paper we explicitly compute P(G
K) when G=S0o(4,1), and show how this result leads to the determination of all irreducible representations of G and its universal covering group Spin(4,1).Partially supported by CONICET (Argentina) grants. 相似文献
6.
Eugenio?Garcia-Pa?eda Pilar?Guardado Alfredo?MaestreEmail author 《Journal of solution chemistry》2004,33(10):1277-1293
Partial molar volumes at infinite dilution, V02, of alkali–metal halides (LiCl, NaCl KCl RbCl CsCl, NaBr, KBr, KI), tetra-n-alkylammonium bromides, R4NBr (R=Me, Et, n-Pr, n-Bu, n-Pen), NaBPh4, and Ph4PCl have been determined in binary solvent mixtures of water with 2-methyl-2-butanol covering the water-rich region and the alcohol-rich region at 298.15 K. V02 for alkali–metal halides show relatively little dependence on the solvent composition. However, in the case of hydrophobic electrolytes the observed effects are more pronounced. A good linear dependence between V02(R4NBr) and the molecular weight of the tetra-n-alkylammonium cation is found. Limiting single-ion volumes have been obtained using the assumption that V0(Ph4P+)–V0(BPh–4)=2.0 cm3-mol–1. The trends in the single-ion volumes are discussed in both solvent regions. 相似文献
7.
The CH3NH2 molecule has been considered as either an important intermediate in methane and ammonia mixtures or a precursor in methylamine and hydrogen mixtures in the synthesis of carbon nitride thin films. The fast Hydrogen (H) abstraction from CH3NH2 is an important process involved in the formation of HCN or CNH in the chemical vapor deposition (CVD) of carbon nitride thin films. The energetic and kinetic characteristics of the H abstraction reaction from CH3NH2 by atomic H used in CVD of beta-C3N4 were studied using ab initio direct dynamics methods for the first time. Two primary processes were identified for this reaction: H abstraction from the CH3 group and H abstraction from the NH2 group. On the basis of ab initio data, the rate constants of each channel have been deduced by canonical variational transition state theory with small-curvature tunneling correction over a wide temperature range of 200 to approximately 3000 K. The theoretical results were compared with available experimental data. 相似文献
8.
The solubility parameter of poly(hexamethylene oxide) has been estimated by measuring solution viscosities and by turbidimetric titrations in a series of solvents. From both experimental methods, a value of () was obtained, whence the cohesive energy density is 274.5 J cm?3 (65.6 cal cm?3). These experimental values are compared with those calculated by empirical methods. 相似文献
9.
Marta Elena Díaz-García Fausto Alava-Moreno Alfredo Sanz-Medel 《Mikrochimica acta》1994,113(3-6):211-222
A new optical sensor phase for potassium ions has been developed based on the immobilization of the pH-dependent fluorogenic crown ether 4-acryloylamidobenzo-18-crown-6 on the non-ionic polymeric resin Amberlite XAD-2.Two different optical designs, a flow-through sensor and a fibre optic probetype sensor (optrode), have been constructed and their analytical performance characteristics have been evaluated. The resulting fluorimetric sensors for K+ ions exhibited detection limits of 0.4 or 0.8 M of K+ (16 g/l or 31 g/l), depending on the design, while the linear response occurred from 1 to 25 M of the metal concentrations. The precision, evaluated as the relative standard deviation of measurements of K+ levels at around ten times the detection limit (e.g. 5 M), turned out to be around ±2%.Advantageous features of this fluorimetric sensing phase and optrode include ease of construction, simplicity of use, reversibility, short response times (ca. 1 min full scale deflection) selectivity and operational stability, suitable for sensing potassium at low levels in complex matrices such as biological fluids.The fluorimetric optical sensor has been successfully applied to the direct determination of potassium in clinically important samples (serum and urine) and in natural waters. Very good accuracy has been obtained just using adequate synthetic aqueous potassium standards for calibration. 相似文献
10.