keyword
MENU ▼
Read by QxMD icon Read
search

Silica

keyword
https://www.readbyqxmd.com/read/28231528/identification-of-uv-absorbing-extractables-from-rubber-closures-used-in-containers-of-injectable-powder-and-safety-assessment-of-leachables-in-the-drug
#1
Yulei Wei, Ying Wu, Tingli Zhu, Zhiyan Li, Yilan Zhang
Rubber closures have been of great concern to regulatory authorities on account of their potential safety risks to patients. The aim of our work is to provide part of data about the compatibility of the injectable powder and its packaging materials for the drug registration. In this report, methodologies were established to study the system of the preparation. Firstly, three major extractables were isolated by semi-preparative HPLC method combined with silica gel-based chromatographic methods. NMR spectra including 1D NMR ((1)H, (13)C, DEPT135) and 2D NMR (COSY, HSQC, HMBC) were introduced to identify the extractables, besides HPLC, GC-MS, ESI-MS/MS and HRMS...
February 16, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28230746/oxidation-of-5-chloromethylfurfural-cmf-to-2-5-diformylfuran-dff
#2
Ana I Vicente, Jaime A S Coelho, Svilen P Simeonov, Hristina I Lazarova, Margarita D Popova, Carlos A M Afonso
2,5-Diformylfuran (DFF) is an important biorenewable building block, namely for the manufacture of new polymers that may replace existing materials derived from limited fossil fuel resources. The current reported methods for the preparation of DFF are mainly derived from the oxidation of 5-hydroxymethylfurfural (HMF) and, to a lesser extent, directly from fructose. 5-Chloromethylfurfural (CMF) has been considered an alternative to HMF as an intermediate building block due to its advantages regarding stability, polarity, and availability from glucose and cellulose...
February 20, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28229590/impacts-of-crosslinkers-on-biological-effects-of-mesoporous-silica-nanoparticles
#3
Yi-Ping Chen, Si-Han Wu, I-Chih Chen, Chien-Tsu Chen
Chemically synthesized crosslinkers play decisive roles in variable cargos attached to nanoparticles (NPs). Previous studies reported that surface properties, such as the size, charge, and surface chemistry, are particularly important determinants influencing the biological fate and actions of NPs and cells. Recent studies also focused on the relationship of serum proteins with the surface properties of NPs (also called the protein corona), which is recognized as a key factor in determining the cytotoxicity and biodistribution...
February 23, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28229522/fused-silica-capillaries-with-two-segments-of-different-internal-diameters-and-inner-surface-roughnesses-prepared-by-etching-with-supercritical-water-and-used-for-volume-coupling-electrophoresis
#4
Marie Horká, Pavel Karásek, Michal Roth, Karel Šlais
In the present work, single-piece fused silica capillaries with two different internal diameter segments featuring different inner surface roughness were prepared by new etching technology with supercritical water and used for volume coupling electrophoresis. The concept of separation and on-line pre-concentration of analytes in high conductivity matrix is based on the on-line large-volume sample pre-concentration by the combination of transient isotachophoretic stacking and sweeping of charged proteins in micellar electrokinetic chromatography using non-ionogenic surfactant...
February 22, 2017: Electrophoresis
https://www.readbyqxmd.com/read/28229136/pt-nanoparticles-immobilized-in-mesostructured-silica-a-non-leaching-catalyst-for-1-octene-hydrosilylation
#5
Thomas Galeandro-Diamant, Reine Sayah, Marie-Line Zanota, Sébastien Marrot, Laurent Veyre, Chloé Thieuleux, Valérie Meille
A catalyst containing small (ca. 2.5 nm) and crystalline Pt nanoparticles embedded into the walls of a mesostructured silica framework was found to be highly active in alkene hydrosilylation reaching TONs of ca. 10(5). More importantly, no Pt leaching was detected. This result is remarkable because Pt leaching is a recurrent problem in alkene hydrosilylation, which often prevents heterogeneous catalysts from being used industrially. This result is in contrast to the significant Pt leaching observed for other Pt/SiO2 catalysts...
February 23, 2017: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/28226244/molecularly-organic-inorganic-hybrid-hollow-mesoporous-organosilica-nanocapsules-with-tumor-specific-biodegradability-and-enhanced-chemotherapeutic-functionality
#6
Ping Huang, Yu Chen, Han Lin, Luodan Yu, Linlin Zhang, Liying Wang, Yufang Zhu, Jianlin Shi
Based on the intrinsic features of high stability and unique multifunctionality, inorganic nanoparticles have shown remarkable potentials in combating cancer, but their biodegradability and biocompatibility are still under debate. As a paradigm, this work successfully demonstrates that framework organic-inorganic hybridization can endow the inorganic mesoporous silica nanocarriers with unique tumor-sensitive biodegradability and high biocompatibility. Based on a "chemical homology" mechanism, molecularly organic-inorganic hybridized hollow mesoporous organosilica nanocapsules (HMONs) with high dispersity and sub-50 nm particle dimension were constructed in mass production...
February 15, 2017: Biomaterials
https://www.readbyqxmd.com/read/28225584/preferential-alignment-of-incommensurate-block-copolymer-dot-arrays-forming-moir%C3%A3-superstructures
#7
Cong Jin, Brian C Olsen, Erik J Luber, Jillian M Buriak
Block copolymer (BCP) self-assembly is of great interest as a cost-effective method for large-scale, high-resolution nanopattern fabrication. Directed self-assembly can induce long-range order and registration, reduce defect-density, and enable access to patterns of higher complexity. Here we demonstrate preferential orientation of two incommensurate BCP dot arrays. A bottom layer of hexagonal silica dots is prepared via typical self-assembly from a PS-b-PDMS block copolymer. Self-assembly of a second, or top, layer of a different a PS-b-PDMS block copolymer that forms a hexagonal dot pattern with different periodicity, results in a predictable Moiré superstructure...
February 22, 2017: ACS Nano
https://www.readbyqxmd.com/read/28225215/enantioseparation-characteristics-of-the-chiral-stationary-phases-based-on-natural-and-regenerated-chitins
#8
Xiao-Meng Mei, Wei Chen, Zheng-Wu Bai
Natural and regenerated chitins were derivatized with 3,5-dimethyphenyl isocyanate. The corresponding chiral stationary phases were prepared by coating the resulting chitin derivatives on 3-aminopropyl silica gel. The swelling capacity of the chitin derivatives, enantioseparation capability as well as eluents tolerance of the chiral stationary phases were evaluated. The results demonstrated there was no remarkable difference in enantioseparation capability between natural and regenerated chitins based chiral stationary phases...
February 22, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28224787/non-radiation-cellular-thermometry-based-on-interfacial-thermally-induced-phase-transformation-in-polymer-coating-of-optical-microfiber
#9
Yunyun Huang, Tuan Guo, Zhuang Tian, Bo Yu, Mingfei Ding, Xiangping Li, BaiOu Guan
A non-radiation based approach based on thermoresponsive polyer coated silica microfibers has been developed. A highly thermoresponsive and bio-compatible pNIPAM was surface functionlized to conjugate to the tapered silica microfiber with waist diameter of 7.5 μm. The interfacial phase transtition of coating triggered by the LCST cause a drastic molecular morphological change in body temperature range of 35-42 oC. This surface morphological change strongly modulates optical path difference between the high order and fundamental mode propagating in the microfiber due to the evanescent-field interaction, and therefore shifts the intermodal interference fringe...
February 22, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28224154/unexpectedly-high-concentrations-of-monoterpenes-in-a-study-of-uk-homes
#10
Chunting Michelle Wang, Benjamin Barratt, Nicola Carslaw, Artemis Doutsi, Rachel E Dunmore, Martyn W Ward, Alastair C Lewis
The abundance of volatile organic compounds (VOCs) found in homes depends on many factors such as emissions, ventilation and the oxidative environment and these are evolving over time, reflecting changes in chemical use, behaviour and building design/materials. The concentrations of VOCs in 25 UK homes of varying ages, design and occupancy were quantified using continuous indoor air sampling over five days. Air was collected through low flow (1 mL min(-1)) constant flow restrictors into evacuated 6 L internally silica-treated canisters until the canisters reached atmospheric pressure...
February 22, 2017: Environmental Science. Processes & Impacts
https://www.readbyqxmd.com/read/28224153/synthesis-and-characterization-of-a-series-of-novel-perovskite-type-lamno3-keggin-type-polyoxometalate-hybrid-nanomaterials-for-fast-and-selective-removal-of-cationic-dyes-from-aqueous-solutions
#11
Saeed Farhadi, Farzaneh Mahmoudi, Mostafa M Amini, Michal Dusek, Marketa Jarosova
In this paper, Keggin-type heteropoly acids H3PMo12O40 (PMo12), H3PW12O40 (PW12) and H4SiW12O40 (SiW12) were successfully supported on silica-coated perovskite type LaMnO3 nanoparticles by a simple acid-base reaction. These novel hybrid nanomaterials (denoted as LaMnO3@SiO2/PMo12 (1), LaMnO3@SiO2/PW12 (2), and LaMnO3@SiO2/SiW12 (3)) were characterized by means of FT-IR, PXRD, inductively coupled plasma (ICP) spectrometry, SEM, EDX, TEM and BET surface area analysis. Furthermore, the adsorption abilities of 1-3 were tested towards cationic methylene blue (MB) and anionic methyl orange (MO) dyes...
February 22, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/28224141/adsorption-behaviors-and-vibrational-spectra-of-hydrogen-peroxide-molecules-at-quartz-water-interfaces
#12
Yeqing Lv, Xinran Wang, Xiaobin Yu, Shili Zheng, Shaona Wang, Yi Zhang, Hao Du
The effect of H2O2 concentration on the change of H-bonds at a water/quartz interface was systematically examined by surface-specific sum-frequency generation (SFG) spectroscopy. Molecular dynamics (MD) simulation was further utilized to interpret the specific molecular dynamics as well as the configuration and evolution of water and H2O2 molecules at the interface. The results from this study demonstrated the important role of surface H-bonds on determination of the stability of adsorbed H2O2 at solvated, silica, xerogel surfaces...
February 22, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28224056/evaluation-and-comparison-of-fta-card-and-ctab-dna-extraction-methods-for-non-agricultural-taxa
#13
Chloe S Siegel, Florence O Stevenson, Elizabeth A Zimmer
PREMISE OF THE STUDY: An efficient, effective DNA extraction method is necessary for comprehensive analysis of plant genomes. This study analyzed the quality of DNA obtained using paper FTA cards prepared directly in the field when compared to the more traditional cetyltrimethylammonium bromide (CTAB)-based extraction methods from silica-dried samples. METHODS: DNA was extracted using FTA cards according to the manufacturer's protocol. In parallel, CTAB-based extractions were done using the automated AutoGen DNA isolation system...
February 2017: Applications in Plant Sciences
https://www.readbyqxmd.com/read/28222740/dibutyryl-camp-attenuates-pulmonary-fibrosis-by-blocking-myofibroblast-differentiation-via-pka-creb-cbp-signaling-in-rats-with-silicosis
#14
Yan Liu, Hong Xu, Yucong Geng, Dingjie Xu, Lijuan Zhang, Yi Yang, Zhongqiu Wei, Bonan Zhang, Shifeng Li, Xuemin Gao, Ruimin Wang, Xianghong Zhang, Darrell Brann, Fang Yang
BACKGROUND: Myofibroblasts play a major role in the synthesis of extracellular matrix (ECM) and the stimulation of these cells is thought to play an important role in the development of silicosis. The present study was undertaken to investigate the anti-fibrotic effects of dibutyryl-cAMP (db-cAMP) on rats induced by silica. METHODS: A HOPE MED 8050 exposure control apparatus was used to create the silicosis model. Rats were randomly divided into 4 groups: 1)controls for 16 w; 2)silicosis for 16 w; 3)db-cAMP pre-treatment; 4) db-cAMP post-treatment...
February 21, 2017: Respiratory Research
https://www.readbyqxmd.com/read/28221981/dry-transfer-inoculation-of-low-moisture-spices-containing-antimicrobial-compounds
#15
Ian M Hildebrandt, Chuxuan Hu, Elizabeth M Grasso-Kelley, Peiran Ye, Nathan M Anderson, Susanne E Keller
Inoculation of a food product for use in subsequent validation studies typically makes use of a high concentration cocktail of microorganisms suspended in aqueous media. However, this inoculation method may prove difficult particularly when the food product is a low-moisture food containing antimicrobial compounds, such as some dried spices. In this study, a dry transfer method for inoculation of clove powder, oregano leaves, ginger powder, and ground black pepper with a five-serovar cocktail of Salmonella was developed and compared with a traditional aqueous inoculation procedure...
February 2017: Journal of Food Protection
https://www.readbyqxmd.com/read/28221779/experimental-assessment-of-photon-fluence-rate-distributions-in-a-medium-pressure-uv-photoreactor
#16
Mengkai Li, Zhimin Qiang, Chen Wang, James R Bolton, Ernest R Blatchley
The performance of a medium-pressure (MP) mercury lamp photoreactor is strongly influenced by the spatial photon fluence rate (PFR) distributions, which are wavelength-dependent. To address this issue, PFR distributions in an MP lamp photoreactor were measured using a 360-degree response micro-fluorescent silica detector (MFSD). To accurately express the optical behavior in an MP photoreactor, PFR, MFSD response PFR (PFRMFSD), and effective germicidal PFR (PFRGER) were defined and compared. The measured axial and radial PFRMFSD values agreed well with the corresponding results from a simulation model (UVCalc®)...
February 21, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28221026/nanomechanics-of-ph-responsive-drug-loaded-bi-layered-polymer-grafts
#17
Prathima Chandra Nalam, Hyun-Su Lee, Nupur Bhatt, Robert W Carpick, David M Eckmann, Russell J Composto
Stimuli-responsive polymer films play an important role in the development of smart antibacterial coatings. In this study, we consider complementary architectures of polyelectrolyte films including a thin chitosan layer (CH), poly (acrylic acid) (PAA) brushes and a bilayer structure of CH grafted to PAA brushes (CH/PAA) as possible candidates for targeted drug delivery platforms. Atomic force microscopy (AFM) was employed to study the structure-mechanical property relationship for these mono- and bi- layered polymer grafts at pH 7...
February 21, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28221001/synthesis-of-dual-stimuli-responsive-microcontainers-with-two-payloads-in-different-storage-spaces-for-preprogrammable-release
#18
Ying Cong, Qiuju Li, Min Chen, Limin Wu
Stimuli-responsive microcontainers have become a major topic of interest, from fundamental aspects to applications in materials science. However, microcontainers that enable the loading of multiple species and programmable release are mostly unexplored. Herein, we describe the design and synthesis of a dual-responsive organic/inorganic hybrid microcontainer with two payloads in separate storage spaces that is formed by the rapid UV-initiated polymerization of Pickering emulsions. The stellate mesopore silica nanoparticles with poly(N-isopropylacrylamide) grafted inside the mesopores were loaded with one compound (Nile red) and used as Pickering emulsifiers to stabilize oil-in-water droplets...
February 21, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28220973/enzyme-controlled-nanodevice-for-acetylcholine-triggered-cargo-delivery-based-on-janus-au-mesoporous-silica-nanoparticles
#19
Antoni Llopis-Lorente, Paula Diez, Cristina de la Torre, Alfredo Sanchez, Felix Sancenon, Elena Aznar, Maria D Marcos, Paloma Martínez-Ruíz, Ramón Martínez-Máñez, Reynaldo Villalonga
This work reports a new gated nanodevice for acetylcholine-triggered cargo delivery. We prepared and characterized Janus Au-mesoporous silica nanoparticles functionalized with acetylcholinesterase on the Au face and with supramolecular β-cyclodextrin:benzimidazole inclusion complexes as caps on the mesoporous silica face. The nanodevice is able to selectively deliver the cargo in the presence of acetylcholine via enzyme-mediated acetylcholine hydrolysis, locally lowering the pH and opening the supramolecular gate...
February 21, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28220860/siliceous-spicules-in-a-vauxiid-sponge-demospongia-from-the-kaili-biota-cambrian-stage-5-guizhou-south-china
#20
X-L Yang, Y-L Zhao, L E Babcock, J Peng
Fossils of the sponge Angulosuspongia sinensis from calcareous mudstones of the middle and upper part of the Kaili Formation (Cambrian Stage 5) in the Jianhe area of Guizhou province, South China, exhibit an apparently reticulate pattern, characteristic of the Vauxiidae. Energy Dispersive X-Ray Spectrometry (EDS) and Raman spectroscopy analysis indicate the presence of silica in the skeletal elements of these fossils, suggesting that this taxon possessed a skeleton comprised of spicules. This is the first confirmation of siliceous skeletal elements in fossils of the family Vauxiidae, and it lends support to the hypothesis that some early demosponges possessed biomineralized siliceous skeletons, which were subsequently lost and replaced by spongin later in the evolutionary history of this lineage...
February 21, 2017: Scientific Reports
keyword
keyword
15976
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"