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Dual‐signal amplification strategy for ultrasensitive chemiluminescence detection of PDGF–BB in capillary electrophoresis 下载免费PDF全文
Jun‐Tao Cao Hui Wang Shu‐Wei Ren Yong‐Hong Chen Yan‐Ming Liu 《Biomedical chromatography : BMC》2015,29(12):1866-1870
Many efforts have been made toward the achievement of high sensitivity in capillary electrophoresis coupled with chemiluminescence detection (CE‐CL). This work describes a novel dual‐signal amplification strategy for highly specific and ultrasensitive CL detection of human platelet‐derived growth factor–BB (PDGF–BB) using both aptamer and horseradish peroxidase (HRP) modified gold nanoparticles (HRP–AuNPs–aptamer) as nanoprobes in CE. Both AuNPs and HRP in the nanoprobes could amplify the CL signals in the luminol–H2O2 CL system, owing to the excellent catalytic behavior of AuNPs and HRP in the CL system. Meanwhile, the high affinity of aptamer modified on the AuNPs allows detection with high specificity. As proof‐of‐concept, the proposed method was employed to quantify the concentration of PDGF–BB from 0.50 to 250 fm with a detection limit of 0.21 fm. The applicability of the assay was further demonstrated in the analysis of PDGF–BB in human serum samples with acceptable accuracy and reliability. The result of this study exhibits distinct advantages, such as high sensitivity, good specificity, simplicity, and very small sample consumption. The good performances of the proposed strategy provide a powerful avenue for ultrasensitive detection of rare proteins in biological sample, showing great promise in biochemical analysis. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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End group polarity and block symmetry effects on cloud point and hydrodynamic diameter of thermoresponsive block copolymers 下载免费PDF全文
Xu Xiang Xiaochu Ding Ning Chen Beilu Zhang Patricia A. Heiden 《Journal of polymer science. Part A, Polymer chemistry》2015,53(24):2838-2848
Thermoresponsive block copolymers are of interest for delivery vehicles in the body. Often an interior domain is designed for the active agent and the exterior domain provides stability in the bloodstream, and may carry a targeting ligand. There is still much to learn about how block sequence and chain end identity affect micelle structure, size, and cloud points. Here, hydrophilic oligo(ethylene glycol) methyl ether acrylate and more hydrophobic di(ethylene glycol) methyl ether methacrylate monomers were polymerized to give amphiphilic block copolymers with amphiphilic chain ends. The block sequence and chain end identity were both controlled by appropriate choice of RAFT chain transfer agents to study the effect of ‘matched’ and ‘mismatched’ chain end polarity with amphiphilic block sequence. The affect of matching or mismatching chain end polarity and block sequence was studied on the hydrodynamic diameter, cloud point, and temperature range of the chain collapse on linear di‐ and triblock copolymers and star diblock polymers. The affects of matching or mismatching chain end polarity were significant with linear diblock copolymers but more complex with triblock and star copolymers. Explanations of these results may help guide others in designing thermoresponsive block copolymers. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2838–2848 相似文献
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Bo Xiang Yanli Qi Shichao Wang 《International Journal of Polymer Analysis and Characterization》2015,20(6):529-540
A number of cool materials have been designed and used in hot weather to minimize the heat coming from sunlight. Traditionally, solar reflectance and infrared emittance were measured to characterize the cooling properties of cool materials. However, these methods could represent the cooling property only indirectly. In this work, a sandwich structure device that can straightforwardly measure the cooling properties of cool materials was designed. Two cool materials, including high-density polyethylene (HDPE) and polyvinyl chloride (PVC), were selected to verify the device. For the purpose of comparison, UV-vis-NIR spectral characterization was also used to evaluate the cooling properties of the selected materials. The results, especially for the HDPE/Green 260 composite sample, which presents much lower solar reflectance but better cooling property, indicated that the cooling properties cannot be entirely represented by only the reflectance or transmittance, and the sandwich structure device was able to make up for this deficiency. 相似文献
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Zihao Yang Junzhi Cui Yufeng Nie Zhiqiang Huang Meizhen Xiang 《Acta Mechanica Sinica》2015,31(5):762-776
In this paper,a statistical second-order twoscale(SSOTS) method is developed to simulate the dynamic thcrmo-mechanical performances of the statistically inhomogeneous materials.For this kind of composite material,the random distribution characteristics of particles,including the shape,size,orientation,spatial location,and volume fractions,are all considered.Firstly,the repre.sentation for the microscopic configuration of the statistically inhomogeneous materials is described.Secondly,the SSOTS formulation for the dynamic thermo-mechanical coupled problem is proposed in a constructive way,including the cell problems,effective thermal and mechanical parameters,homogenized problems,and the SSOTS formulas of the temperatures,displacements,heat flux densities and stresses.And then the algorithm procedure corresponding to the SSOTS method is brought forward.The numerical results obtained by using the SSOTS algorithm are compared with those by classical methods.In addition,the thermo-mechanical coupling effect is studied by comparing the results of coupled case with those of uncoupled case.It demonstrates that the coupling effect on the temperatures,heat flux densities,displacements,and stresses is very distinct.The results show that the SSOTS method is valid to predict the dynamic thermo-mechanical coupled performances of statistically inhomogeneous materials. 相似文献