Read by QxMD icon Read


Bahareh Babamiri, Abdollah Salimi, Rahman Hallaj
In the present study, an ultrasensitive electrochemiluminescence (ECL) aptasensing assay for selective detection of Hg(2+) was designed. In this electrochemiluminescence resonance energy transfer (ECL-RET) approach, Fe3O4@SiO2/dendrimers/QDs exhibited amplified ECL emissions (switch "on" state) and with the hybridization between T-rich ssDNA(S1) immobilized on the Fe3O4@SiO2/dendrimers/QDs and AuNPs modified with complementary aptamer (AuNPs-S2), the ECL of QDs nanocomposites was efficiently quenched (switch "off" state)...
November 10, 2017: Biosensors & Bioelectronics
Qiqi Yuan, Junlin He, Yazhen Niu, Jun Chen, Yilin Zhao, Yuchan Zhang, Chao Yu
α2,3-sialylated glycans (α2,3-sial-Gs) are one of the significant tumour biomarkers for the early diagnosis of cancer. In this work, a neoteric sandwich-type biosensor was developed for detecting α2,3-sial-Gs using 4-mercaptophenylboronic acid (4-MPBA) to construct a novel molecular recognition system by the coordination of a boron atom of 4-MPBA to the amide group of Neu5Ac in the α2,3-sial-Gs structure. Amino-functionalized fullerene coupled with palladium-platinum bimetallic alloy nanocrystals (n-C60-PdPt) was synthesized to modify the surface of a glassy carbon electrode (GCE) because the n-C60 nanomaterial affords a large surface area for the on-site reduction of bimetallic alloy nanoparticles and an excellent capacity for electron transfer...
November 18, 2017: Biosensors & Bioelectronics
Marcin P Grzelczak, Stephen P Danks, Robert C Klip, Domagoj Belic, Adnana Zaulet, Casper Kunstmann-Olsen, Dan F Bradley, Tatsuya Tsukuda, Clara Viñas, Francesc Teixidor, Jonathan J Abramson, Mathias Brust
2-3 nm carborane-capped gold nanoparticles (Au/carborane NPs) can act as artificial ion transporters across biological membranes. The particles themselves are large hydrophobic anions that have the ability to disperse in aqueous media and to partition over both sides of a phospholipid bilayer membrane. Their presence therefore causes a membrane potential that is determined by the relative concentrations of particles on each side of the membrane according to the Nernst-Equation. The particles tend to adsorb to both sides of the membrane and can flip across if changes in membrane potential require their repartitioning...
November 21, 2017: ACS Nano
Felix S Geitner, Thomas F Fässler
The reaction of NHC(Dipp)CuCl with the silicide phases A12Si17 (A: K, K/Rb, Rb) in NH3(l) yields [NHC(Dipp)Cu(η(4)-Si9)](3-) (1) as only the third example of a substituted [Si9] cluster. The corresponding salts A3[A(2.2.2-crypt)]3[NHC(Dipp)Cu(η(4)-Si9)]2·26NH3 (A: K (1a), K/Rb (1b), Rb (1c)) crystallize isostructurally in the space group P1[combining macron] and have been characterized by single crystal structure determination. ESI-MS and NMR experiments reveal that the anion [NHC(Dipp)Cu(η(4)-Si9)](3-) can also be transferred to pyridine or acetonitrile solutions at low temperature...
November 21, 2017: Chemical Communications: Chem Comm
Fengyu Yang, Yonglan Liu, Yanxian Zhang, Baiping Ren, Jianxiong Xu, Jie Zheng
Rational design of biomaterials with antifouling properties still remains a challenge, but is important for many bench-to-bedside applications for biomedical implants, drug delivery carriers, and marine coatings. Herein we synthesized and characterized poly(N-acryloylglycinamide) (polyNAGA) and then grafted poly(NAGA) onto Au substrate to form polymer brushes with well controlled film stability, wettability and thickness using the surface-initiated atom transfer radical polymerization (SI-ATRP). The NAGA monomer integrates two hydrophilic amides on the side chain to enhance surface hydration, which is thought as a critical contributor to antifouling property...
November 21, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Karen J Meech, Robert Weryk, Marco Micheli, Jan T Kleyna, Olivier R Hainaut, Robert Jedicke, Richard J Wainscoat, Kenneth C Chambers, Jacqueline V Keane, Andreea Petric, Larry Denneau, Eugene Magnier, Travis Berger, Mark E Huber, Heather Flewelling, Chris Waters, Eva Schunova-Lilly, Serge Chastel
None of the approximately 750,000 known asteroids and comets is thought to have originated outside our Solar System, but formation models suggest that orbital migration of the giant planets ejected a large fraction of the original planetesimals into interstellar space(1). The predicted interstellar number density(2) of icy interstellar objects of 2.4 × 10(-4) au(-3) suggested that these should have been detected by surveys, yet hitherto none had been seen. Many decades of asteroid and comet characterization have yielded formation models that explain the mass distribution, chemical abundances and planetary configuration of today's Solar System, but until now there has been no way to tell if our Solar System is typical...
November 20, 2017: Nature
Jin Zhu, Xiaolong Li, Wei Zheng, Biao Wang, Yubo Tian
The results of this reported work indicated that gold nanoparticles (Au NPs) arrays self-assembled on Indium Tin Oxide (ITO) glasses can obtain broader localized surface plasmon resonance (LSPR) wavelength range and higher sensitivity than the bare quartz. The results of surface electric field calculated using Finite Difference Time Domain (FDTD) showed that the electric field of nanoparticles on ITO glasses is enhanced and the repulsive forces within each particle is weakened. According to the dipolar interaction mechanism, a weakened repulsive forces within each particle lead to a lower resonance frequency and a strong redshift of the LSPR spectra...
November 21, 2017: Nanotechnology
Tomofumi Fujino, Akihito Yokosuka, Harutaka Ichikawa, Toshiyuki Oshima, Yoshihiro Mimaki, Makio Hayakawa
The spirostanol saponin AU-1 from Agavaceae plants stimulates the expression of the glycolytic enzyme phosphoglycerate mutase (PGAM) in ACHN cells. We hypothesized that this may arise from the downregulation of the NAD(+)-dependent deacetylase SIRT1. In this article, we showed that, unlike in renal adenocarcinoma cells, AU-1 does not affect the expression of SIRT1 in the normal renal cell-derived cell line HK-2. Consistent with the lack of a downregulation of SIRT1, AU-1 did not upregulate, but rather decreased PGAM expression...
November 20, 2017: Journal of Natural Medicines
Kun-Che Kao, Yoshinori Kuroiwa, Hiroyasu Nishi, Tetsu Tatsuma
Metal-semiconductor plasmonic nanostructures are capable of converting light energy through plasmon-induced charge separation (PICS), providing fruitful new strategies to utilize solar energy in various fields, including photocatalysis. Here, we enhance the PICS efficiencies for hydrogen evolution from water at a Pt cathode coupled with a TiO2/Au photoanode by coating the TiO2/Au with a p-type NiO layer on which a Pt co-catalyst is deposited. PICS occurs at the Au-TiO2 interface under visible light. The electrons injected from the Au nanoparticles into TiO2 are transported to the Pt cathode and cause hydrogen evolution from water, the action spectrum of which matches the plasmonic extinction spectrum of the Au nanoparticles...
November 21, 2017: Physical Chemistry Chemical Physics: PCCP
Dianping Tang, Jingjing Ren, Minghua Lu
Herein, a simple and feasible electrochemical immunosensing method for simultaneous voltammetric detection of two immunoglobulin proteins, human IgG (HIgG) and rabbit IgG (RIgG), was developed using two distinguishable signal-generation tags on the same electrode. The immunosensor was prepared by immobilizing two Fab antibody fragments on a gold electrode. After this, Cu and Cd nanocrystals, as nanotags, were synthesized and functionalized with identical detection antibodies. Transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR) were employed to characterize the Cu and Cd nanocrystals...
November 21, 2017: Analyst
Xianzhong Yang, Jing Li, Yuxin Zhao, Jianhua Yang, Liyan Zhou, Zhigao Dai, Xiao Guo, Shanjun Mu, Quanzhen Liu, Chunming Jiang, Mengtao Sun, Jianfang Wang, Wenjie Liang
Plasmonic nanomaterials, along with their assemblies, provide numerous applications due to their profound optical properties. In this work, we report the self-assembly of Au@Ag core-shell nanocuboids (NCs) into staircase superstructures in both vertical and horizontal orientations through two-stage droplet evaporation. Each stair is composed of a uniform well-aligned monolayer of NCs. The gap distance between NCs can be greatly shrunk to boost the corresponding surface-enhanced Raman scattering (SERS) performance using an ethanol wash method...
November 21, 2017: Nanoscale
Ying Sun, Qi Wang, Jianhua Chen, Lei Liu, Li Ding, Ming Shen, Jin Li, Baoshan Han, Yourong Duan
Gold nanoparticle-coated Pluronic-b-poly(L-lysine) nanoparticles (Pluronic-PLL@Au NPs) were synthesized via an easy one-step method and employed as carriers for the delivery of paclitaxel (PTX) in chemo-photothermal therapy, in which Pluronic-PLL acts as the reductant for the formation of AuNPs without the need for an additional reducing agent. METHODS: The deposition of AuNPs on the surface of Pluronic-PLL micelles and the thermal response of the system were followed via ultraviolet-visible spectroscopy and dynamic light scattering...
2017: Theranostics
Zihni Onur Uygun, Çağdaş Şahin, Merve Yilmaz, Yasemin Akçay, Ali Akdemir, Ferhan Sağin
The aim of this study is to develop a nanomaterial-dendrimer composite modified biosensor to detect Fetuin-A (HFA) in real blood samples. For this purpose, we designed an Electrochemical Impedance Spectroscopy (EIS) based anti-Fetuin-A (Anti-HFA) modified biosensor system and tested in real blood samples. Chronoimpedance was also employed. The same samples were analyzed with ELISA and the results were compared for validation of the new system. Gold screen printed electrodes (AuSPE) were used as transducer. Firstly, a self-assembly monolayer (SAM) was formed on gold surface by 4-aminothiophenol (4-ATP), Fullerene and PAMAM-NH2 (G5), layers were formed, consecutively...
November 17, 2017: Analytical Biochemistry
Carmelita G Frondoza, Lowella V Fortuno, Mark W Grzanna, Stacy L Ownby, Angela Y Au, Ann M Rashmir-Raven
Objective Pro-inflammatory mediators such as prostaglandin E-2 (PGE2) play major roles in the pathogenesis of osteoarthritis (OA). Although current pharmacologic treatments reduce inflammation, their prolonged use is associated with deleterious side effects prompting the search for safer and effective alternative strategies. The present study evaluated whether chondrocyte production of PGE2 can be suppressed by the combination of avocado/soybean unsaponifiables (ASU) and α-lipoic acid (LA). Design Chondrocytes from articular cartilage of equine joints were incubated for 24 hours with: (1) control media, (2) ASU, (3) LA, or (4) ASU + LA combination...
January 1, 2017: Cartilage
Amol A Kulkarni, Victor Sebastian
Continuous segmented flow interfacial synthesis of Au nanostructures is demonstrated in a microchannel reactor. This study brings new insights into the growth of nanostructures at continuous interfaces. The size as well as the shape of the nanostructures showed significant dependence on the reactant concentrations, reaction time, temperature and surface tension, which actually controlled the interfacial mass transfer. The microchannel reactor assisted in achieving high interfacial area, as well as uniformity in mass transfer effects...
November 20, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
Juncai Zhao, Zhanfang Ma
Based on the target-induced catalytic hairpin assembly and bimetallic catalyst, the enzyme-free recycling amplification strategy for sensitive detection of prostate specific antigen (PSA) has been designed. The aptamer and its complementary DNA (C-apt) are modified on the magnetic particles. The aptamer-PSA binding event can release the C-apt that triggers the catalytic assembly between hairpin capture DNA and hairpin help DNA. Then the catalytic hairpin assembly leads to cyclic reuse the C-apt and the generation of many opened hairpin capture DNA, which can associate with the prepared Au/Pt-polymethylene blue (PMB) probes to yield electrochemical signal...
November 15, 2017: Biosensors & Bioelectronics
Ying Chen, Yu Li, Dongmei Deng, Haibo He, Xiaoxia Yan, Zhenxin Wang, Chunhai Fan, Liqiang Luo
A novel and sensitive sandwich immunosensor for amperometric determination of carcinoembryonic antigen (CEA) was designed using Au nanoparticles-titanium dioxide-graphene (AuNPs-TiO2-graphene) nanocomposites. Dopamine-functionalized graphene was firstly prepared by π-stacking interaction, and TiO2 was then attached to the surface of dopamine-graphene by the specificity and high affinity of enediol ligands to Ti (IV). Afterwards, AuNPs-TiO2-graphene nanocomposites were synthesized with photo-reduction approach under ultraviolet irradiation...
November 17, 2017: Biosensors & Bioelectronics
Yanhui Zhang, Hongxu Guo, Wen Weng, Ming-Lai Fu
Reduced graphene oxide (RGO) as an electron-conductive medium and photosensitizer have been widely used to construct efficient RGO/semiconductor photocatalysts for solar energy conversion; however, the role of RGO has been largely underestimated. Herein, the surface plasmon resonance (SPR) effect, thermal effect, support effect, and size effect of Au/RGO are demonstrated to play important roles in enhancing the photocatalytic activity, which has not been considered previously. Au/RGO nanocomposites, synthesized via a facile wet chemistry route, exhibit an excellent visible light photocatalytic performance for selective oxidation of benzylic alcohols...
November 20, 2017: Physical Chemistry Chemical Physics: PCCP
Jun Guo, Yin Zhang, Lin Shi, Yanfei Zhu, Megersa Feyissa Mideksa, Ke Hou, Wenshi Zhao, Dawei Wang, Meiting Zhao, Xiaofei Zhang, Jiawei Lv, Jianqi Zhang, Xiaoli Wang, Zhiyong Tang
Hetero-nanostructures featured with both strong plasmon absorption and high catalytic activity are believed to be ideal platforms to realize efficient light-driven catalysis. However, in reality it remains great challenge to acquire high performance catalysis in such hetero-nanostructures due to poor generation and transfer of plamson-induced hot electrons. In this report, we demonstrate that Au nanorod@Pd superstructures (Au@Pd SSs), where the ordered Pd nanoarrays are precisely grown on Au nanorod surfaces via solution-based seed-mediated approach, would be an excellent solution for this challenge...
November 20, 2017: Journal of the American Chemical Society
Anneli Joplin, Seyyed Ali Hosseini Jebeli, Eric Sung, Nathan Diemler, Patrick J Straney, Mustafa Yorulmaz, Wei-Shun Chang, Jill E Millstone, Stephan Link
Bimetallic nanocatalysts have the potential to surmount current limitations in industrial catalysis if their electronic and optical properties can be effectively controlled. However, improving the performance of bimetallic photocatalysts requires a functional understanding of how the intricacies of their morphology and composition dictate every element of their optical response. In this work, we examine Au and Pt-decorated Au nanorods on a single particle level to ascertain how Pt influences the plasmon resonance of the bimetallic nanostructure...
November 20, 2017: ACS Nano
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"