keyword
MENU ▼
Read by QxMD icon Read
search

silsesquioxane

keyword
https://www.readbyqxmd.com/read/30310890/a-polyhedral-oligomeric-silsesquioxane-molecular-sieve-codoped-molecularly-imprinted-polymer-for-gastroretentive-drug-controlled-release-in-vivo
#1
Xu Wang, Fang-Fang Yang, Li-Ping Zhang, Yan-Ping Huang, Zhao-Sheng Liu
Flotation drug delivery system (FDDS) is recognized as an efficient means to improve the therapeutic efficiency and enhance the drug bioavailability. Herein, we have developed a molecularly imprinted polymer (MIP) against capecitabine (CAP) to fabricate a FDDS by exploiting polyhedral oligomeric silsesquioxane (POSS) and Mobil composition of matter no. 41 (MCM-41) as the codopant. The synergistic effect of POSS and MCM-41 endows MIPs with enhanced imprinting effect and improved mass transfer efficiency. The impacts of the type of dopant, the type of functional monomer, the template/functional monomer ratio and the functional monomer/cross-linker ratio on imprinting effect have been investigated in detail...
October 12, 2018: Biomaterials Science
https://www.readbyqxmd.com/read/30277619/multivalent-fucosides-with-nanomolar-affinity-for-the-aspergillus-fumigatus-lectin-flea-prevent-spore-adhesion-to-pneumocytes
#2
Sébastien G Gouin, Victor Lehot, Yoan Brissonnet, Christophe Dussouy, Sami Brument, Aurore Cabanettes, Emilie Gillon, David Deniaud, Annabelle Varrot, Patrice Le Pape
FleA (or AFL), a fucose lectin, was recently identified in the opportunistic mold Aspergillus fumigatus that causes fatal lung infections in immunocompromised patients. We designed di-, hexa- and octavalent fucosides with various spacer arm lengths to block the hexameric FleA via chelation. Microcalorimetry measurements showed that the ethylene glycol (EG) spacer arm length has a strong influence on the binding affinity of the divalent fucosides. The relationship between the EG length and chelate binding efficiency to FleA was explored according to polymer theory...
October 2, 2018: Chemistry: a European Journal
https://www.readbyqxmd.com/read/30272655/single-digit-nanometer-electron-beam-lithography-with-an-aberration-corrected-scanning-transmission-electron-microscope
#3
Fernando E Camino, Vitor R Manfrinato, Aaron Stein, Lihua Zhang, Ming Lu, Eric A Stach, Charles T Black
We demonstrate extension of electron-beam lithography using conventional resists and pattern transfer processes to single-digit nanometer dimensions by employing an aberration-corrected scanning transmission electron microscope as the exposure tool. Here, we present results of single-digit nanometer patterning of two widely used electron-beam resists: poly (methyl methacrylate) and hydrogen silsesquioxane. The method achieves sub-5 nanometer features in poly (methyl methacrylate) and sub-10 nanometer resolution in hydrogen silsesquioxane...
September 14, 2018: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/30262758/self-assembly-and-applications-of-amphiphilic-hybrid-poss-copolymers
#4
REVIEW
Hong Chi, Mingyue Wang, Yiting Xiao, Fuke Wang, Joshy K S
Understanding the mechanism of molecular self-assembly to form well-organized nanostructures is essential in the field of supramolecular chemistry. Particularly, amphiphilic copolymers incorporated with polyhedral oligomeric silsesquioxanes (POSSs) have been one of the most promising materials in material science, engineering, and biomedical fields. In this review, new ideas and research works which have been carried out over the last several years in this relatively new area with a main focus on their mechanism in self-assembly and applications are discussed...
September 27, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/30245809/on-chip-excitation-of-single-germanium-vacancies-in-nanodiamonds-embedded-in-plasmonic-waveguides
#5
Hamidreza Siampour, Shailesh Kumar, Valery A Davydov, Liudmila F Kulikova, Viatcheslav N Agafonov, Sergey I Bozhevolnyi
Monolithic integration of quantum emitters in nanoscale plasmonic circuitry requires low-loss plasmonic configurations capable of confining light well below the diffraction limit. We demonstrated on-chip remote excitation of nanodiamond-embedded single quantum emitters by plasmonic modes of dielectric ridges atop colloidal silver crystals. The nanodiamonds were produced to incorporate single germanium-vacancy (GeV) centres, providing bright, spectrally narrow and stable single-photon sources suitable for highly integrated circuits...
2018: Light, Science & Applications
https://www.readbyqxmd.com/read/30230070/a-diarylethene-based-super-photoswitch-and-its-photomodulation-performance-on-fluorescence-of-conjugated-polymer
#6
Ronghua Liu, Yu Yang, Qianling Cui, Wenqiang Xu, Rui Peng, Lidong Li
Photochromic diarylethene derivatives, which can reversibly switch the fluorescence of adjacent fluorophores between the ON and OFF states under light irradiation, have been widely used to construct photoswitchable materials. Herein, we integrate eight dithienylethene (DTE) groups onto one polyhedral oligomeric silsesquioxanes (POSS) core, obtaining a novel super molecular photoswitch. After being doped into conjugated polymer nanoparticles, the POSS-DTE8 molecules shows a higher contrast on/off photoswitching performance and a quicker responsive speed than free DTE molecules at same molar concentration of photochromic units...
September 19, 2018: Chemistry: a European Journal
https://www.readbyqxmd.com/read/30223245/poly-silsesquioxanes-and-poly-siloxanes-grafted-with-n-acetylcysteine-for-eradicating-mature-bacterial-biofilms-in-water-environment
#7
Maria Nowacka, Anna Rygała, Dorota Kręgiel, Anna Kowalewska
Bacteria adapt to their living environment forming organised biofilms. The survival strategy makes them more resistant to disinfectants, which results in acute biofilm-caused infections, secondary water pollution by biofilm metabolites and bio-corrosion. New, efficient and environmentally friendly strategies must be developed to solve this problem. Water soluble N-acetyl derivative of L-cysteine (NAC) is a non-toxic compound of mucolytic and bacteriostatic properties that can interfere with the formation of biofilms...
September 10, 2018: Colloids and Surfaces. B, Biointerfaces
https://www.readbyqxmd.com/read/30216859/a-star-shaped-poss-containing-polymer-for-cleaner-leather-processing
#8
Lu Jia, Jianzhong Ma, Dangge Gao, William R T Tait, Luyi Sun
A water-based silsesquioxane (POSS)-containing polymer, POSS-PAA, was synthesized by using octavinyl-POSS (V-POSS) and acrylic acid (AA) via interfacial polymerization. The TEM of POSS-PAA showed that the polymer formed a core-shell structure in aqueous solution and was well-dispersed. The star-shaped POSS-PAA and linear PAA were both tanned with 3.5% chromium tanning agent, and leather hide was tanned with 3.5% chromium tanning agent as a control. The results showed that the shrinkage temperature of wet-blue leather treated by POSS-PAA was increased by 3...
January 5, 2019: Journal of Hazardous Materials
https://www.readbyqxmd.com/read/30214717/synthesis-of-water-degradable-silica-nanoparticles-from-carbamate-containing-bridged-silsesquioxane-precursor
#9
Zhe Gao, Seyyed Pouya Hadipour Moghaddam, Hamidreza Ghandehari, Ilya Zharov
Silica nanoparticles (SNPs) are attractive for applications for the delivery of drugs and as imaging agents due to their ease of synthesis and scale up, robust structure, and controllable size and composition. Degradability is one important factor that limits biomedical applications of SNPs. With this in mind, we designed, prepared and characterized novel hydrolysable organosilica nanoparticles (ICPTES-Sorbitol SNPs). These particles were prepared by co-condensation of tetraethoxysilane with a bridged sorbitol-based silsesquioxane precursor containing carbamate linkages...
2018: RSC Advances
https://www.readbyqxmd.com/read/30211531/polyhedral-oligomeric-silsesquioxane-poss-based-cationic-conjugated-oligoelectrolyte-porphyrin-for-efficient-energy-transfer-and-multiamplified-antimicrobial-activity
#10
Jia Chen, Jingyang Shan, Yu Xu, Peng Su, Li Tong, Lihui Yuwen, Lixing Weng, Biqing Bao, Lianhui Wang
Cationic quaternary ammonium (QA) groups and reactive oxygen species as two main approaches for antibacterial study have been intensively studied. Herein, we report a multifunctional antimicrobial agent (porphyrin-POSS-OPVE, PPO), which combines bacterial membrane intercalation, high density of local QA groups, efficient energy transfer, significantly reduced aggregation, and high water solubility into one single molecule. The light-harvesting PPO contains multiple donor-absorbing arms (oligo( p-phenylenevinylene) electrolytes, OPVEs) on its globular periphery and a central porphyrin acceptor in the core by using three-dimensional nanocages (polyhedral oligomeric silsesquioxanes, POSSs) as bridges...
September 26, 2018: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/30194741/alkanethiol-functionalized-organosilicon-monoliths-for-nano-reversed-phase-liquid-chromatography
#11
Cihan Demir, Çiğdem Kip, Ali Tuncel
Organosilicon monoliths carrying chromatographic ligands with different alkyl chain lengths were obtained by thiol-methacrylate photopolymerization. The use of thiol-ene chemistry in the presence of a main monomer with a series of methacrylate functionality (i.e., methacrylate substituted polyhedral oligomeric silsesquioxane) allowed the synthesis of organosilicon monoliths with high cross-linking density and carrying hydrophobic alkyl-chain ligands by a one-pot process. In the synthesis runs, 1-butanethiol, 1-octanethiol, and 1-octadecanethiol were used as the hydrophobic thiol ligands with the number of methylene units between 4 and 18...
September 8, 2018: Electrophoresis
https://www.readbyqxmd.com/read/30184783/silsesquioxane-polymer-as-a-potential-scaffold-for-laryngeal-reconstruction
#12
Nazia Mehrban, James Bowen, Angela Tait, Arnold Darbyshire, Alex K Virasami, Mark W Lowdell, Martin A Birchall
Cancer, disease and trauma to the larynx and their treatment can lead to permanent loss of structures critical to voice, breathing and swallowing. Engineered partial or total laryngeal replacements would need to match the ambitious specifications of replicating functionality, outer biocompatibility, and permissiveness for an inner mucosal lining. Here we present porous polyhedral oligomeric silsesquioxane-poly(carbonate urea) urethane (POSS-PCUU) as a potential scaffold for engineering laryngeal tissue. Specifically, we employ a precipitation and porogen leaching technique for manufacturing the polymer...
November 1, 2018: Materials Science & Engineering. C, Materials for Biological Applications
https://www.readbyqxmd.com/read/30184758/synthesis-and-characterization-of-paclitaxel-imprinted-microparticles-for-controlled-release-of-an-anticancer-drug
#13
Jianwei Bai, Yunan Zhang, Longqi Chen, Huijun Yan, Chunhong Zhang, Lijia Liu, Xiaodong Xu
In this study, novel molecularly imprinted polymer (MIP) microparticles containing methacryl polyhedral oligomeric silsesquioxane (M-POSS) were synthesized through the RAFT precipitation polymerization (RAFTPP) method using paclitaxel (PTX) as the templates. During the course of this investigation, methacrylic acid (MAA) was used as the functional monomer, while ethylene glycol dimethacrylate (EGDMA) was utilized as a cross-linker. The effects of different molar ratios of M-POSS on the microparticles were characterized...
November 1, 2018: Materials Science & Engineering. C, Materials for Biological Applications
https://www.readbyqxmd.com/read/30179802/antibacterial-pcl-electrospun-membranes-containing-synthetic-polypeptides-for-biomedical-purposes
#14
Bo Liu, Tiantian Yao, Lixia Ren, Yunhui Zhao, Xiaoyan Yuan
Electrospun membranes endowed with efficient bactericidal properties have been widely applied in the biomedical field. In this work, polyhedral oligomeric silsesquioxane (POSS) and i-butyl-capped polypeptides, POSS-poly(lysine-co-valine) (PKV) and i-butyl-poly(lysine-co-valine) (KV), were prepared via ring-opening polymerization of N-carboxyanhydride lysine and valine monomers. The synthetic polypeptides, PKV and KV, were facilely added in the poly(ε-caprolactone) (PCL) solution for electrospinning to enable the electrospun membranes to have antibacterial properties for biomedical applications...
August 28, 2018: Colloids and Surfaces. B, Biointerfaces
https://www.readbyqxmd.com/read/30160945/high-cluster-cu-9-cage-silsesquioxanes-synthesis-structure-and-catalytic-activity
#15
Grigorii S Astakhov, Alexey N Bilyachenko, Alexander A Korlyukov, Mikhail M Levitsky, Lidia S Shul'pina, Xavier Bantreil, Frédéric Lamaty, Anna V Vologzhanina, Elena S Shubina, Pavel V Dorovatovskii, Dmytro S Nesterov, Armando J L Pombeiro, Georgiy B Shul'pin
Unusual high-cluster (Cu9 ) cage phenylsilsesquioxanes were obtained via complexation of in situ CuII ,Na-silsesquioxane species formed with phenanthroline and neocuproine. In the first case, phenanthroline, acting as "a silent ligand" (not participating in the composition of the final product), favors the formation of an unprecedented cagelike phenylsilsesquioxane of Cu9 Na6 nuclearity, 1. In the second case, neocuproine ligands withdraws two Cu ions from the metallasilsesquioxane matrix, producing two cationic fragments Cu+ (neocuproine)2 ...
September 17, 2018: Inorganic Chemistry
https://www.readbyqxmd.com/read/30120566/a-3d-nanoscale-polyhedral-oligomeric-silsesquioxanes-network-for-microextraction-of-polycyclic-aromatic-hydrocarbons
#16
Habib Bagheri, Gohar Soofi, Hasan Javanmardi, Majid Karimi
Polyhedral oligomeric silsesquioxanes are 3D nanoscaled materials with large potential in solid phase microextraction (SPME). Here, as a case study, an octaglycidyldimethylsilyl modified polyhedral oligomeric silsesquioxane network is described. It was deposited on a stainless steel wire via a sol-gel method and used as a fiber coating for SPME of aromatic compounds. The uniform pore structure, high surface area, and hydrophobicity of the network make it susceptible toward isolation of non-polar and semi-polar chemical compounds...
August 17, 2018: Mikrochimica Acta
https://www.readbyqxmd.com/read/30106215/smart-transformation-of-a-polyhedral-oligomeric-silsesquioxane-shell-controlled-by-thiolate-silver-i-nanocluster-core-in-cluster-clusters-dendrimers
#17
Si Li, Zhao-Yang Wang, Guang-Gang Gao, Bing Li, Peng Luo, Yu-Jin Kong, Hong Liu, Shuang-Quan Zang
Using polyhedral oligomeric silsesquioxane (POSS) modified by a thiol group as a protected ligand, atom-precise multi-heteorocluster-based dendrimers Ag12 @POSS6 (1 a and 1 b) were assembled. Through the reactive -SH groups, six POSS shell ligands stabilize the central 12-core silver(I) cluster by diverse Ag-S interactions. When such Ag12 @POSS6 complex was stimulated by different solvents (acetone or tetrahydrofuran), the core Ag12 silver(I) cluster underwent reversible structural transformation between flattened cubo-octahedral (in 1 a) and normal cubo-octahedral (in 1 b); concomitantly shell POSS clusters rearranged from pseudo-octahedral to quasi-octahedral...
September 24, 2018: Angewandte Chemie
https://www.readbyqxmd.com/read/30082594/poss-nanofiller-induced-enhancement-of-the-thermomechanical-properties-in-a-fluoroelastomer-terpolymer
#18
Daphné Berthier, Marie-Pierre Deffarges, Nicolas Berton, Mathieu Venin, Florian Lacroix, Bruno Schmaltz, Yohan Tendron, Eric Pestel, François Tran-Van, Stéphane Méo
The present study reports on the use of three types of polyhedral oligomeric silsesquioxanes (POSS) nanoparticles with various organic substituents as fillers in a fluoroelastomer (FKM). A series of/POSS elastomer composite thin films is prepared. Microstructural SEM/TEM (scanning electron microscopy/transmission electron microscopy) imaging reveals a dispersion state allowing the presence of micron-sized domains. The influence of POSS content is studied in order to optimize thermal stability and mechanical properties of the composite thin films...
August 6, 2018: Materials
https://www.readbyqxmd.com/read/30074601/hierarchically-ordered-structures-of-disk-cube-triads-containing-hexa-peri-hexabenzocoronene-and-polyhedral-oligomeric-silsesquioxane
#19
Wei Zhang, Kehua Gu, Pingping Hou, Xiaolin Lyu, Hongbing Pan, Zhihao Shen, Xing-He Fan
Obtaining nanoscale-ordered structures is important for the development of nanotechnology. We designed and synthesized a series of disk-cube triads containing one hexa-peri-hexabenzocoronene (HBC) and two polyhedral oligomeric silsesquioxane (POSS) moieties, HBC-2POSS. The two POSS units were linked via ester or amide bonds. With the amide linkage used, the hydrogen bonding that was introduced affected the balance between the π-π interaction of HBC cores and crystallization interaction of POSS units. Hierarchically ordered structures were obtained from HBC-2POSS triads owing to the synergistic effect of multiple secondary interactions: π-π interaction, hydrogen bonding, and crystallization interaction...
August 15, 2018: Soft Matter
https://www.readbyqxmd.com/read/30055448/fabrication-of-si-and-ge-nanoarrays-through-graphoepitaxial-directed-hardmask-block-copolymer-self-assembly
#20
Anushka S Gangnaik, Tandra Ghoshal, Yordan M Georgiev, Michael A Morris, Justin D Holmes
Films of self assembled diblock copolymers (BCPs) have attracted significant attention for generating semiconductor nanoarrays of sizes below 100 nm through a simple low cost approach for device fabrication. A challenging abstract is controlling microdomain orientation and ordering dictated by complex interplay of surface energies, polymer-solvent interactions and domain spacing. In context, microphase separated poly (styrene-b-ethylene oxide) (PS-b-PEO) thin films is illustrated to fabricate nanopatterns on silicon and germanium materials trenches...
December 1, 2018: Journal of Colloid and Interface Science
keyword
keyword
159830
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"