keyword
MENU ▼
Read by QxMD icon Read
search

Surface chemistry

keyword
https://www.readbyqxmd.com/read/28538098/two-dimensional-metal-organic-framework-nanosheets-as-an-enzyme-inhibitor-modulation-of-the-%C3%AE-chymotrypsin-activity
#1
Ming Xu, Shuai Yuan, Xin-Yu Chen, Yu-Jie Chang, Gregory Steven Day, Zhi-Yuan Gu, Hong-Cai Zhou
Two-dimensional metal-organic framework (MOF) nanosheets are utilized as effective enzyme inhibitors, providing an in-spiring means to enhance the control of cellular processes as well as improve our understanding of the surface chemistry between MOFs and enzymes. In this paper, we demonstrated that the activity of α-Chymotrypsin (ChT) can be effectively inhibited with 96.9% inhibition by the 2-D Cu(bpy)2(OTf)2 nanosheets, while the other Zn2(bim)4 nanosheets show no significant inhibition effect towards ChT...
May 24, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28537771/atmospheric-constraints-on-the-surface-uv-environment-of-mars-at-3-9%C3%A2-ga-relevant-to-prebiotic-chemistry
#2
Sukrit Ranjan, Robin Wordsworth, Dimitar D Sasselov
Recent findings suggest that Mars may have been a clement environment for the emergence of life and may even have compared favorably to Earth in this regard. These findings have revived interest in the hypothesis that prebiotically important molecules or even nascent life may have formed on Mars and been transferred to Earth. UV light plays a key role in prebiotic chemistry. Characterizing the early martian surface UV environment is key to understanding how Mars compares to Earth as a venue for prebiotic chemistry...
May 24, 2017: Astrobiology
https://www.readbyqxmd.com/read/28537750/detection-of-microrna-by-electrocatalytic-amplification-a-general-approach-for-single-particle-biosensing
#3
Alma D Castañeda, Nicholas J Brenes, Aditya Kondajji, Richard M Crooks
Here we report a sensing scheme for detection of microRNA (miRNA) using electrocatalytic amplification (ECA). ECA is a method in which nanoparticles (NPs) that are catalytic for a specific electrochemical reaction collide with an inert electrode surface. Each collision results in a detectable current transient. In the present article, we show that this general approach can be extended to detection of miRNA. Specifically, PtNPs are modified with a single-strand DNA (ssDNA) shell that is complementary to the miRNA target...
May 24, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28535070/polarity-control-of-heteroepitaxial-gan-nanowires-on-diamond
#4
Martin Hetzl, Max Kraut, Theresa Hoffmann, Martin Stutzmann
Group III-nitride materials such as GaN nanowires are characterized by a spontaneous polarization within the crystal. The sign of the resulting sheet charge at the top and bottom facet of a GaN nanowire is determined by the orientation of the wurtzite bilayer of the different atomic species, called N and Ga polarity. We investigate the polarity distribution of heteroepitaxial GaN nanowires on different substrates and demonstrate polarity control of GaN nanowires on diamond. Kelvin Probe Force Microscopy is used to determine the polarity of individual selective area-grown and self-assembled nanowires over a large scale...
May 23, 2017: Nano Letters
https://www.readbyqxmd.com/read/28535068/a-conformal-lithium-fluoride-protection-layer-on-three-dimensional-lithium-by-non-hazardous-gaseous-reagent-freon
#5
Dingchang Lin, Yayuan Liu, Wei Chen, Guangmin Zhou, Kai Liu, Bruce S Dunn, Yi Cui
Research on lithium (Li) metal chemistry has been rapidly gaining momentum nowadays not only because of the appealing high theoretical capacity, but also its indispensable role in the next-generation Li-S and Li-air batteries. However, two root problems of Li metal, namely high reactivity and infinite relative volume change during cycling, bring about numerous other challenges that impede its practical applications. In the past, extensive studies have targeted these two root causes by either improving interfacial stability or constructing a stable host...
May 23, 2017: Nano Letters
https://www.readbyqxmd.com/read/28535061/sitting-phase-monolayers-of-polymerizable-phospholipids-create-dimensional-molecular-scale-wetting-control-for-scalable-solution-based-patterning-of-layered-materials
#6
Shi Wah Choong, Shane R Russell, Jae Jin Bang, Justin K Patterson, Shelley A Claridge
The use of dimensionally ordered ligands on layered materials to direct local electronic structure and interactions with the environment promises to streamline integration into nanostructured electronic, optoelectronic, sensing, and nanofluidic interfaces. Substantial progress has been made in using ligands to control substrate electronic structure. Conversely, using the exposed face of the ligand layer to structure wetting and binding interactions, particularly with scalable solution- or spray-processed materials, remains a significant challenge...
May 23, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28534784/incorporation-of-solvent-effect-into-multi-objective-evolutionary-algorithm-for-improved-protein-structure-prediction
#7
Shangce Gao, Jiujun Cheng, Yuki Todo, Mengchu Zhou
The problem of predicting the three-dimensional structure of a protein from its one-dimensional sequence has been called the "holy grail of molecular biology", and it has become an important part of structural genomics projects. Despite the rapid developments in computer technology and computational intelligence, it remains challenging and fascinating. In this paper, to solve it we propose a multi-objective evolutionary algorithm. We decompose the protein energy function Chemistry at HARvard Macromolecular Mechanics force fields into bond and non-bond energies as the first and second objectives...
May 17, 2017: IEEE/ACM Transactions on Computational Biology and Bioinformatics
https://www.readbyqxmd.com/read/28534592/thermo-electrochemical-cells-for-waste-heat-harvesting-progress-and-perspectives
#8
M F Dupont, D R MacFarlane, J M Pringle
Thermo-electrochemical cells (also called thermocells) are promising devices for harvesting waste heat for the sustainable production of energy. Research into thermocells has increased significantly in recent years, driven by advantages such as their ability to continuously convert heat into electrical energy without producing emissions or consuming materials. Until relatively recently, the commercial viability of thermocells was limited by their low power output and conversion efficiency. However, there have lately been significant advances in thermocell performance as a result of improvements to the electrode materials, electrolyte and redox chemistry and various features of the cell design...
May 23, 2017: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/28534406/relationships-between-exciton-dissociation-and-slow-recombination-within-znse-cds-and-cdse-cds-dot-in-rod-heterostructures
#9
Amanda N Grennell, James K Utterback, Orion M Pearce, Molly B Wilker, Gordana Dukovic
Type-II and quasi type-II heterostructure nanocrystals are known to exhibit extended excited-state lifetimes compared to their single material counterparts because of reduced wavefunction overlap between the electron and hole. However, due to fast and efficient hole trapping and non-uniform morphologies, the photophysics of dot-in-rod heterostructures are more rich and complex than this simple picture. Using transient absorption spectroscopy, we observe that the behavior of electrons in the CdS "rod" or "bulb" regions of non-uniform ZnSe/CdS and CdSe/CdS dot-in-rods is similar regardless of the "dot" material, which supports previous work demonstrating that hole trapping and particle morphology drive electron dynamics...
May 23, 2017: Nano Letters
https://www.readbyqxmd.com/read/28534207/construction-of-polyarylenes-with-various-structural-features-via-bergman-cyclization-polymerization
#10
REVIEW
Youfu Wang, Shudan Chen, Aiguo Hu
Synthetic polymer chemistry is a fundamental part of polymer science, and highly efficient polymerization reactions are essential for the synthesis of high-performance polymers. Development of new synthetic methods for emerging polymer science is of great importance in this regard. Bergman cyclization is a chemical process in which highly reactive aryl diradicals form from enediyne precursors, having a strong impact in a number of fields including pharmaceutics, synthetic chemistry, and materials science. Diradical intermediates stemming from enediynes can cause DNA cleavage under physiological conditions, leading to the strong cytotoxicity of many naturally occurring enediyne antibiotics...
June 2017: Topics in Current Chemistry (Journal)
https://www.readbyqxmd.com/read/28532109/lactoferrin-modified-graphene-oxide-iron-oxide-nanocomposite-for-glioma-targeted-drug-delivery
#11
Meng-Meng Song, Huai-Liang Xu, Jun-Xing Liang, Hui-Hui Xiang, Rui Liu, Yu-Xian Shen
Targeting delivery of drugs in a specific manner represents a potential powerful technology in gliomas. Herein, we prepared a multifunctional targeted delivery system based on graphene oxide (GO) that contains a molecular bio-targeting ligand and superparamagnetic iron oxide nanoparticles on the surface of GO for magnetic targeting. Superparamagnetic Fe3O4 nanoparticles was loaded on the surface of GO via chemical precipitation method to form GO@Fe3O4 nanocomposites. Lactoferrin (Lf), an iron-transporting serum glycoprotein that binds to receptors overexpressed at the surface of glioma cells and vascular endothelial cell of the blood brain barrier, was chosen as the targeted ligand to construct the targeted delivery system Lf@GO@Fe3O4 through EDC/NHS chemistry...
August 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
https://www.readbyqxmd.com/read/28532078/enhancement-of-fibroblast-growing-on-the-mannosylated-surface-of-cellulose-membranes
#12
Simone Birkheur, Paula Cristina de Sousa Faria-Tischer, Cesar A Tischer, Elisângela Flávia Pimentel, Marcio Fronza, Denise Coutinho Endringer, Anna Paola Butera, Renato Márcio Ribeiro-Viana
Bacterial cellulose membrane is a biomaterial with high value in the biomedical field. Many groups have been making efforts to promote chemical modifications of its structure and, consequently, add new characteristics. Recently, our group has developed a methodology to insert monoester succinic acid in bacterial cellulose membrane without disrupting the microfibril network and bind a protein on it. Considering the role of carbohydrates in the molecular recognition process in biological events, we continued these studies by inserting covalently multiples copies of aryl monosaccharide to bacterial cellulose succinylated and to study the in vitro tissue compatibility using fibroblasts...
August 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
https://www.readbyqxmd.com/read/28532058/interaction-of-nanostructured-tio2-biointerfaces-with-stem-cells-and-biofilm-forming-bacteria
#13
Mukta Kulkarni, Ita Junkar, Petr Humpolíček, Zdenka Capáková, Katarzyna Anna Radaszkiewicz, Nikola Mikušová, Jiří Pacherník, Marián Lehocký, Aleš Iglič, Markéta Hanáčková, Miran Mozetič
Nanostructured TiO2 nanotubes (NTs) of diameters from 15 to 100nm were fabricated by an electrochemical anodization process. Biofilm-positive strains of Bacillus cereus and Pseudomonas aeruginosa behaved similarly on all TiO2 NTs as well as on native titanium (Ti) foil. The adhesion and growth of mesenchymal stem cells (MSc), embryonic stem cells (ESc), and pure cardiomyocytes derived from ESc exhibited significant differences. MSc as well as ESc were, in contrast to cardiomyocytes, able to adhere, and grow on TiO2 NTs...
August 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
https://www.readbyqxmd.com/read/28530835/on-the-formation-of-epitaxially-connected-quantum-dot-solids-nucleation-and-coherent-phase-transition
#14
Kevin Whitham, Tobias Hanrath
The formation of epitaxially connected quantum dot solids involves a complex interplay of interfacial assembly, surface chemistry, and irreversible directed attachment. We describe the basic mechanism in context of a coherent phase transition with distinct nucleation and propagation steps. The proposed mechanism explains how defects in the pre-assembled structure influence nucleation and how basic geometric relationships govern the transformation from hexagonal assemblies of isolated dots to interconnected solids with square symmetry...
May 22, 2017: Journal of Physical Chemistry Letters
https://www.readbyqxmd.com/read/28530806/photoluminescent-hybrids-of-cellulose-nanocrystals-and-carbon-quantum-dots-as-cytocompatible-probes-for-in-vitro-bio-imaging
#15
Jiaqi Guo, Dongfei Liu, Ilari Filpponen, Leena-Sisko Johansson, Jani-Markus Malho, Sakeena Quraishi, Falk Liebner, Hélder A Santos, Orlando J Rojas
We present an approach to construct biocompatible and photoluminescent hybrid materials comprised of carbon quantum dots (CQD) and TEMPO-oxidized cellulose nanocrystals (TO-CNC). First, the amino-functionalized carbon quantum dots (NH2-CQD) were synthesized using a simple microwave method and the TO-CNCs were prepared by hydrochloric acid (HCl) hydrolysis followed by TEMPO-mediated oxidation. The conjugation of NH2-CQD and TO-CNC was conducted via carbodiimide-assisted coupling chemistry. The synthesized TO-CNC@CQD hybrid nanomaterials were characterized using X-ray photoelectron spectroscopy, cryo-transmittance electron microscopy, confocal microscopy and fluorescence spectroscopy...
May 22, 2017: Biomacromolecules
https://www.readbyqxmd.com/read/28530651/surface-attached-molecules-control-staphylococcus-aureus-quorum-sensing-and-biofilm-development
#16
Minyoung Kevin Kim, Aishan Zhao, Ashley Wang, Zachary Z Brown, Tom W Muir, Howard A Stone, Bonnie L Bassler
Bacteria use a process called quorum sensing to communicate and orchestrate collective behaviours, including virulence factor secretion and biofilm formation. Quorum sensing relies on the production, release, accumulation and population-wide detection of signal molecules called autoinducers. Here, we develop concepts to coat surfaces with quorum-sensing-manipulation molecules as a method to control collective behaviours. We probe this strategy using Staphylococcus aureus. Pro- and anti-quorum-sensing molecules can be covalently attached to surfaces using click chemistry, where they retain their abilities to influence bacterial behaviours...
May 22, 2017: Nature Microbiology
https://www.readbyqxmd.com/read/28530092/fibroblast-cytophilic-and-hela-cytotoxic-dual-function-carbon-nanoribbon-network-platform
#17
A K M Rezaul Haque Chowdhury, Bo Tan, Krishnan Venkatakrishnan
Carbon nanomaterials have emerged as a promising material in cancer diagnosis and therapy. Carbon nanomaterials/nanostructures (C-C molecular structure) act as a carrier/skeleton and require further surface modification through functionalization with chemicals or biomolecules to attain a cell response. We report the synthesis of a novel carbon nanoribbon network (CNRN) platform that possesses a combination of C-C and C-O bond architecture. The bioactive CNRN showed enhanced ability for cell adhesion. Most importantly, it induced opposite cell responses from healthy cells and cancerous cells, cytophilic to fibroblasts but cytotoxic to HeLa cells...
May 22, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28529382/reversibly-manipulating-the-surface-chemistry-of-polymeric-nanostructures-via-a-grafting-to-approach-mediated-by-nucleobase-interactions
#18
Zan Hua, Robert Keogh, Zhen Li, Thomas R Wilks, Guosong Chen, Rachel K O'Reilly
"Grafting to" polymeric nanostructures or surfaces is a simple and versatile approach to achieve functionalization. Herein, we describe the formation of mixed polymer-grafted nanoparticles through a supramolecular "grafting to" method that exploits multiple hydrogen-bonding interactions between the thymine (T)-containing cores of preformed micelles and the complementary nucleobase adenine (A) of added diblock copolymers. To demonstrate this new "grafting to" approach, mixed-corona polymeric nanoparticles with different sizes were prepared by the addition of a series of complementary diblock copolymers containing thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) to a preformed micelle with a different coronal forming block, poly(4-acryloylmorpholine) (PNAM)...
May 9, 2017: Macromolecules
https://www.readbyqxmd.com/read/28528626/colloid-particle-formulations-for-antimicrobial-applications
#19
REVIEW
Ahmed F Halbus, Tommy S Horozov, Vesselin N Paunov
Colloidal particles are being extensively studied in various antimicrobial applications due to their small size to volume ratio and ability to exhibit a wide spectrum of antibacterial, antifungal, antialgal and antiviral action. The present review focuses on various nanoparticles (NPs) of inorganic, organic and hybrid materials, and discusses some of the methods for their preparation as well as mechanisms of their antimicrobial action. We consider the antimicrobial applications of metal oxide nanoparticles (ZnO, MgO, CuO, Cu2O, Al2O3, TiO2, CeO2 and Y2O3), metal nanoparticles (NPs), such as copper, silver and gold, metal hydroxide NPs such as Mg(OH)2 as well as hybrid NPs made from biodegradable materials, such as chitosan, lignin and dextran, loaded with other antimicrobial agents...
May 12, 2017: Advances in Colloid and Interface Science
https://www.readbyqxmd.com/read/28527981/an-identification-of-the-soft-polyelectrolyte-gel-like-layer-on-silica-colloids-using-atomic-force-and-electron-microscopy
#20
Jiří Škvarla, Juraj Škvarla
A procedure is introduced for measuring the radius of spherical colloid particles from the curvature of upper parts of their central cross-sectional profiles obtained by atomic force microscopy (AFM). To minimize the possible compression and displacement of the spheres, AFM is operated in a mode rendering a constant ultralow pN force on the tip. The procedure allows us to evaluate the mean radius of nearly monodisperse submicrometer spheres of silica in their natively hydrated state in aqueous electrolyte solutions, irrespective of whether they are coagulated or not...
May 16, 2017: Ultramicroscopy
keyword
keyword
55593
1
2
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"