Dual‐signal amplification strategy for ultrasensitive chemiluminescence detection of PDGF–BB in capillary electrophoresis

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.     

Luminescent Ag6Au6 Heterometallic Ethisterone Cluster and Probe for Estrogen Receptor α

A heterometallic cluster [Ag₆Au₆(ethisterone)₁₂] of an unprecedented topology was synthesized and characterized. A sensitive and specific probe for estrogen receptor α (ERα) has been developed for the first time based on the enhancement of the Ag₆Au₆ luminescence.     

Research and Evaluation on Wear in Power-Shift Steering Transmission Through Oil Spectral Analysis with RKPCA Method

The most common methodology used in element concentration measurement and analyzing of wear particles is Atomic emission (AE) spectroscopy .The present paper presents an evaluation method on wear in po...     

Porous carbon nanospheres with moderately oriented domains for EDLC electrode

Porous carbon nanospheres with moderately oriented microcrystalline structures were prepared via a relatively simple synthetic route in this article. CTAB acted as a structure‐directing agent to induce small sulfonated pitch (SP) pieces to assemble orderly. By this means, the formation of carbon nanospheres was simultaneous with the moderate orientation of carbon microcrystalline without additional process. Owing to the moderately oriented microcrystalline structures, the resultant sample CNS3 possessed a high e‐conductivity of 62.5 S/m. When used as an electrode material for EDLCs, it showed excellent electrochemical properties even without any conductive agent. In an organic electrolyte, the resultant sample CNS3 possessed a high specific capacitance of 155 F/g at 20 A/g and outstanding cycle life with 94.2% capacity retention after 10,000 cycles. This work puts forward a novel design for carbon nanospheres with moderately oriented domains by a simple and energy‐efficient means.     

On Fermat Diophantine functional equations,little Picard theorem and beyond

Aequationes mathematicae - We discuss equivalence conditions for the non-existence of non-trivial meromorphic solutions to the Fermat Diophantine equation $$f^m(z)+g^n(z)=1$$ with integers $$m,n\ge...     

A pH-Sensitive Zwitterionic Iron Complex Probe with High Biocompatibility for Tumor-Specific Magnetic Resonance Imaging

Accurate diagnosis of tumor characteristics, including its location and boundary, is of immense value to subsequent therapy. Activatable magnetic resonance imaging (MRI) contrast agents that respond to tumor-specific microenvironments, such as the redox state, pH, and enzyme activity, enable better mapping of tumor tissue. However, the practical application of most reported activatable agents is hampered by problems including potential toxicity, inefficient elimination, and slow activation. In this study, we developed a zwitterionic iron complex (Fe-ZDS) as a positive MRI contrast agent for tumor-specific imaging. Fe-ZDS could dissociate in weakly acidic solution rapidly, accompanied by clear longitudinal relaxivity (r₁) enhancement, which enabled the complex to act as a pH-sensitive contrast agent for tumor-specific MR imaging. In vivo experiments showed that Fe-ZDS rapidly enhanced the tumor-to-normal contrast ratio by >40 %, which assisted in distinguishing the tumor boundary. Furthermore, Fe-ZDS circulated freely in the bloodstream and was excreted relatively safely via kidneys owing to its zwitterionic nature. Therefore, Fe-ZDS is an ideal candidate for a tumor-specific MRI contrast agent and holds considerable potential for clinical translation.