Read by QxMD icon Read


Eman F Aboelfetoh, Rania A El-Shenody, Mohamed M Ghobara
Stable colloidal silver nanoparticles (AgNPs) were synthesized using Caulerpa serrulata (green marine algae) aqueous extract as an efficient reducing and stabilizing agent. This method is considered to be a sustainable alternate to the more complicated chemical procedures. To achieve the optimization synthesis of AgNPs, several effects such as extract concentration, contact time, pH values, and temperature were examined. The synthesized AgNPs were characterized by UV-Vis spectroscopy, FT-IR, XRD, and HR-TEM...
July 2017: Environmental Monitoring and Assessment
Nezih Tolga Yardimci, Semih Cakmakyapan, Soroosh Hemmati, Mona Jarrahi
The scope and potential uses of time-domain terahertz imaging and spectroscopy are mainly limited by the low optical-to-terahertz conversion efficiency of photoconductive terahertz sources. State-of-the-art photoconductive sources utilize short-carrier-lifetime semiconductors to recombine carriers that cannot contribute to efficient terahertz generation and cause additional thermal dissipation. Here, we present a novel photoconductive terahertz source that offers a significantly higher efficiency compared with terahertz sources fabricated on short-carrier-lifetime substrates...
June 23, 2017: Scientific Reports
Ramkumar Rajamani, Sophie Wu, Iyoncy Rodrigo, Mian Gao, Simon Low, Lisa Megson, David Wensel, Rick Pieschl, Debra Post-Munson, John Watson, David R Langley, Michael Ahlijanian, Linda Bristow, James Herrington
NaV1.7 is genetically implicated in human pain perception. Rare gain of function mutations in NaV1.7 lead to spontaneous pain in humans whereas loss of function mutations result in congenital insensitivity to pain (CIP). Hence, agents that specifically modulate the function of NaV1.7 have the potential to yield novel therapeutics to treat pain. The complexity of the channel and the challenges to generate recombinant cell lines with high NaV1.7 expression have led to a templated target strategy approach employing chimeras with the bacterial channel, NavAb...
June 23, 2017: Molecular Pharmacology
Hicham Bakkali, Eduardo Blanco, Manuel Dominguez, Jose S Garitaonandia
Discontinuous multilayer (DML) thin films, which consist of nano-granular metals (NGMs) embedded in a dielectric matrix, have attracted significant interest as engineered plasmonic metamaterials. In this study, a systematic layer-by-layer deposition of three-dimensional sub-wavelength periodic plasmonic DML structures via the radio frequency sputtering of a composite target has been reported. The overall optical response of the DML films composed of AuAl2O3 NGM homogenous layers, which are periodically sandwiched between two amorphous Al2O3 layers, are studied using reflection spectroscopic ellipsometry and transmission spectroscopy techniques...
June 23, 2017: Nanotechnology
Günter Kewes, Kathrin Herrmann, Rogelio Rodríguez-Oliveros, Alexander Kuhlicke, Oliver Benson, Kurt Busch
We present a semiclassical analytic model for spherical core-shell surface plasmon lasers. Within this model, we drop the widely used one-mode approximations in favor of fully electromagnetic Mie theory. This allows for incorporation of realistic gain relaxation rates that so far are massively underestimated. Especially, higher order modes can undermine and even reverse the beneficial effects of the strong Purcell effect in such systems. Our model gives a clear view on gain and resonator requirements, as well as on the output characteristics that will help experimenters to design more efficient particle-based spasers...
June 9, 2017: Physical Review Letters
Renming Liu, Zhang-Kai Zhou, Yi-Cong Yu, Tengwei Zhang, Hao Wang, Guanghui Liu, Yuming Wei, Huanjun Chen, Xue-Hua Wang
Reaching the quantum optics limit of strong light-matter interactions between a single exciton and a plasmon mode is highly desirable, because it opens up possibilities to explore room-temperature quantum devices operating at the single-photon level. However, two challenges severely hinder the realization of this limit: the integration of single-exciton emitters with plasmonic nanostructures and making the coupling strength at the single-exciton level overcome the large damping of the plasmon mode. Here, we demonstrate that these two hindrances can be overcome by attaching individual J aggregates to single cuboid Au@Ag nanorods...
June 9, 2017: Physical Review Letters
Marie Richard-Lacroix, Yao Zhang, Zhenchao Dong, Volker Deckert
Recent years have seen tremendous improvement of our understanding of high resolution reachable in TERS experiments, forcing us to re-evaluate our understanding of the intrinsic limits of this field, but also exposing several inconsistencies. On the one hand, more and more recent experimental results have provided us with clear indications of spatial resolutions down to a few nanometres or even on the subnanometre scale. Moreover, lessons learned from recent theoretical investigations clearly support such high resolutions, and vice versa the obvious theoretical impossibility to evade high resolution from a purely plasmonic point of view...
June 23, 2017: Chemical Society Reviews
Abdul Rahim Ferhan, Gamaliel Junren Ma, Joshua A Jackman, Tun Naw Sut, Jae Hyeon Park, Nam-Joon Cho
The integration of supported lipid membranes with surface-based nanoplasmonic arrays provides a powerful sensing approach to investigate biointerfacial phenomena at membrane interfaces. While a growing number of lipid vesicles, protein, and nucleic acid systems have been explored with nanoplasmonic sensors, there has been only very limited investigation of the interactions between solution-phase nanomaterials and supported lipid membranes. Herein, we established a surface-based localized surface plasmon resonance (LSPR) sensing platform for probing the interaction of dielectric nanoparticles with supported lipid bilayer (SLB)-coated, plasmonic nanodisk arrays...
June 23, 2017: Sensors
Xuan-Hung Pham, Eunil Hahm, Tae Han Kim, Hyung-Mo Kim, Sang Hun Lee, Yoon-Sik Lee, Dae Hong Jeong, Bong-Hyun Jun
In this study, we prepared adenosine triphosphate (ATP) encapsulated liposomes, and assessed their applicability for the surface enhanced Raman scattering (SERS)-based assays with gold-silver alloy (Au@Ag)-assembled silica nanoparticles (NPs; SiO₂@Au@Ag). The liposomes were prepared by the thin film hydration method from a mixture of l-α-phosphatidylcholine, cholesterol, and PE-PEG2000 in chloroform; evaporating the solvent, followed by hydration of the resulting thin film with ATP in phosphate-buffered saline (PBS)...
June 23, 2017: Sensors
Alexander N Kharlamov, John A Feinstein, John A Cramer, John A Boothroyd, Ekaterina V Shishkina, Vladimir Shur
AIM: The safety options in nanomedicine raise an issue of the optimal niche at the real-world clinical practice. METHODS: This is an observational prospective cohort analysis of the 5-year clinical outcomes at the intention-to-treat population (nano vs ferro vs stenting; n = 180) of NANOM first-in-man trial (NCT01270139). RESULTS: Mortality (6 vs 9 vs 10 cases of cardiac death in groups, p < 0.05), major adverse cardiovascular events (14...
June 23, 2017: Future Cardiology
Miao Wang, Fuyang Xu, Yu Lin, Bing Cao, Linghua Chen, Chinhua Wang, Jianfeng Wang, Ke Xu
We proposed and demonstrated an integrated high energy efficient and high linearly polarized InGaN/GaN green LED grown on (0001) oriented sapphire with combined metasurface polarizing converter and polarizer system. It is different from those conventional polarized light emissions generated with plasmonic metallic grating in which at least 50% high energy loss occurs inherently due to high reflection of the transverse electric (TE) component of an electric field. A reflecting metasurface, with a two dimensional elliptic metal cylinder array (EMCA) that functions as a half-wave plate, was integrated at the bottom of a LED such that the back-reflected TE component, that is otherwise lost by a dielectric/metal bi-layered wire grids (DMBiWG) polarizer on the top emitting surface of the LED, can be converted to desired transverse magnetic (TM) polarized emission after reflecting from the metasurface...
June 23, 2017: Nanoscale
Miguel Moreno, Poh Yih Pow, Tan Su Teng Tabitha, Sonali Nirmal, Andreas Larsson, Krishna Radhakrishnan, Jayabalan Nirmal, Soo Tng Quah, Susana Geifman Shochat, Rupesh Agrawal, Subbu Venkatraman
BACKGROUND: This paper describes the synthesis of thiolated chitosan-based hydrogels with varying degrees of crosslinking that has been utilized to modulate release kinetics of two clinically relevant FDA-approved anti-VEGF protein drugs, ranibizumab and aflibercept. These hydrogels have been fabricated into disc shaped structures for potential use as patches on ocular surface. METHODS: Protein conformational changes and aggregation after loading and release was evaluated by circular dichroism (CD), steady-state tryptophan fluorescence spectroscopy, electrophoresis and size-exclusion chromatography (SEC)...
June 23, 2017: Expert Opinion on Drug Delivery
Pierre Fauché, Christian Gebhardt, Maxim Sukharev, Renaud A L Vallée
Achieving and controlling strong light-matter interactions in many-body systems is of paramount importance both for fundamental understanding and potential applications. In this paper we demonstrate both experimentally and theoretically how to manipulate strong coupling between the Bragg-plasmon mode supported by an organo-metallic array and molecular excitons in the form of J-aggregates dispersed on the hybrid structure. We observe experimentally the transition from a conventional strong coupling regime exhibiting the usual upper and lower polaritonic branches to a more complex regime, where a third nondispersive mode is seen, as the concentration of J-aggregates is increased...
June 22, 2017: Scientific Reports
Wafa I Abdel-Fattah, M M Eid, Sh I Abd El-Moez, E Mohamed, Ghareib W Ali
Biogenic Ag@Pd core-shell nanoparticles were greenly synthesized within two plant extracts aiming at enhanced anticancer/bactericidal functions. These functions were verified for the two Pd@Ag biogenic core-shell nanoparticles (BCSnp) with constant Pd to several Ag contents. BCSnp were synthesized within two extracts of Almond nuts and Black Berry fruits, four samples each, through simple, low cost and echo friendly microwave route. The BCSnp Surface Plasmon Resonance (SPR) was detected via UV/visible spectrophotometer...
June 19, 2017: Life Sciences
Brigita Rožič, Jérôme Fresnais, Celine Molinaro, Joseph Calixte, Shivakumar Umadevi, Stephanie Lau-Truong, Nordin Felidj, Tobias Kraus, Fabrice Charra, Vincent Dupuis, Torsten Hegmann, Celine Fiorini-Debuisschert, Bruno Gallas, Emmanuelle Lacaze
We show that the use of oriented linear arrays of smectic A defects, the so-called smectic oily streaks, enables the orientation of gold nanorods (GNRs) for a large range of GNR diameters, ranging from 7 to 48 nm, and for various ligands. For the small GNRs it enables oriented end-to-end small chains of GNRs when the density is increased from around 2 GNRs/μm(2) to around 6 GNRs/μm(2). We have characterized the orientation of single GNRs by spectrophotometry and two-photon luminescence (TPL). A strongly anisotropic absorption of the composites and an on-off switching of GNR luminescence, both controlled by incident light polarization, are observed, revealing an orientation of the GNRs mostly parallel to the oily streaks...
June 22, 2017: ACS Nano
Chengliang Wu, Alan R Stafford, James C Fredenburgh, Jeffrey I Weitz, Ann Gils, Paul J Declerck, Paul Y Kim
The thrombin-thrombomodulin (TM) complex activates thrombin-activable fibrinolysis inhibitor (TAFI) more efficiently than thrombin alone. The exosite on TAFI required for its TM-dependent activation by thrombin has not been identified. Based on previous work by us and others, we generated TAFI variants with one or more of residues Lys 42, Lys 43, Lys 44 and Arg 12 within the activation peptide mutated to alanine. Mutation of one, two, or three Lys residues or the Arg residue alone decreased the catalytic efficiency of TAFI activation by thrombin-TM by 2...
June 22, 2017: Thrombosis and Haemostasis
M Fernanda Cardinal, Emma Vander Ende, Ryan A Hackler, Michael O McAnally, Peter C Stair, George C Schatz, Richard P Van Duyne
Surface-enhanced Raman scattering (SERS) spectroscopy has evolved into a cross-disciplinary analytical technique by unveiling relevant chemical, biological, material, and structural information. The focus of this review is on two critical properties for successfully expanding applications of SERS spectroscopy: quality of the plasmonic substrate and molecule localization to the substrate. In this review, we discuss recent work on quantifying SERS distance dependence, key factors for substrate characterization and performance evaluation, expansion of SERS applications through substrate development for UV plasmonics and short-distance capture strategies for optimizing analyte-surface structures...
June 22, 2017: Chemical Society Reviews
Tanja Deckert-Gaudig, Atsushi Taguchi, Satoshi Kawata, Volker Deckert
An analytical technique operating at the nanoscale must be flexible regarding variable experimental conditions while ideally also being highly specific, extremely sensitive, and spatially confined. In this respect, tip-enhanced Raman scattering (TERS) has been demonstrated to be ideally suited to, e.g., elucidating chemical reaction mechanisms, determining the distribution of components and identifying and localizing specific molecular structures at the nanometre scale. TERS combines the specificity of Raman spectroscopy with the high spatial resolution of scanning probe microscopies by utilizing plasmonic nanostructures to confine the incident electromagnetic field and increase it by many orders of magnitude...
June 22, 2017: Chemical Society Reviews
Chentao Zhang, Kun Lin, Yuanqing Huang, Jianhuan Zhang
Surface-enhanced Raman scattering (SERS) has been extensively investigated as an effective approach for trace species detection. Silver nanostructures are high-sensitivity SERS substrates in common use, but their poor chemical stability impedes practical applications. Herein, a stable and sensitive SERS substrate based on the hybrid structures of graphene/silver film/laser-textured Si (G/Ag/LTSi) was developed, and a simple, rapid, and low-cost fabrication approach was explored. Abundant nanoparticles were directly created and deposited on the Si surface via laser ablation...
June 22, 2017: Sensors
Orian Elimelech, Jing Liu, Anna M Plonka, Anatoly I Frenkel, Uri Banin
Doping semiconductor nanocrystals (NCs) is a key yet under-explored approach for tuning their electronic properties. An important route for doping in NCs is vacancy formation. Herein, the size and concentration dependence of doping is studied in Cu2S NCs through a redox reaction with iodine leading to vacancy formation accompanied by a localized surface plasmon response. X-ray spectroscopy and diffraction reveal transformation from Cu2S to Cu depleted phases along with CuI formation. Higher efficiency of the reaction is observed for larger NCs...
June 22, 2017: Angewandte Chemie
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"