Search results
Search for "silica" in Full Text gives 393 result(s) in Beilstein Journal of Nanotechnology. Showing first 200.
Interactions at the cell membrane and pathways of internalization of nano-sized materials for nanomedicine
Beilstein J. Nanotechnol. 2020, 11, 338–353, doi:10.3762/bjnano.11.25
- of 100 nm silica nanoparticles incubated with human serum were found to interact with their corresponding receptors, low-density lipoprotein receptor and Fc-gamma receptor I, respectively [17]. Similarly, lipid nanoparticles were efficiently targeted to the hepatocytes upon adsorption of apoE on
- required to wrap a lipid membrane around a nanoparticle with high aspect ratio [148]. However, also in relation to this aspect, conflicting results were found in which cross-linked poly(ethylene glycol) hydrogels or mesoporous silica particles with higher aspect ratio were internalized quicker and more
- 3) were both taken up by HeLa cells by a combination of clathrin-mediated and caveolae-mediated endocytosis (based on cholesterol and tyrosine kinase dependence) [125]. On the other hand, in another study, the entry of cylindric, worm-like, and spherical silica particles in A549 and RAW264.7 cells
An advanced structural characterization of templated meso-macroporous carbon monoliths by small- and wide-angle scattering techniques
Beilstein J. Nanotechnol. 2020, 11, 310–322, doi:10.3762/bjnano.11.23
- create meso- or macropores into the carbon system templating approaches have become a routine strategy. One prominent attempt is hard-templating based on silica monoliths with a bimodal pore size distribution (meso- and macropores) and a hierarchical pore network [35][36][37][38]. The SiO2 solid is
- surface area and a high permeability. Due to big macropores the material can achieve high flow rates for separation processes, and the mesopores within the walls of the macropores lead to a high surface area, which is beneficial for adsorption processes [39][40]. Carbon replicas based on silica monoliths
- . In both cases, the hard-templated carbon was exposed to two substantially different temperatures, namely 800 and 3000 °C. This means that two porous carbon materials were treated at 800 and two at 3000 °C. In short, in the hard-templating process the pristine silica monoliths were infiltrated by a
Rational design of block copolymer self-assemblies in photodynamic therapy
Beilstein J. Nanotechnol. 2020, 11, 180–212, doi:10.3762/bjnano.11.15
Fabrication of Ag-modified hollow titania spheres via controlled silver diffusion in Ag–TiO2 core–shell nanostructures
Beilstein J. Nanotechnol. 2020, 11, 141–146, doi:10.3762/bjnano.11.12
- fabricated in a multistep process including a two-step hydrothermal treatment [11]. Ag-modified TiO2 HSs showing efficient photocatalysis in the visible-light range were synthesized in a multistep process through a sacrificial core technique using AgBr as the core [12]. A hard-templating method with a silica
Molecular architectonics of DNA for functional nanoarchitectures
Beilstein J. Nanotechnol. 2020, 11, 124–140, doi:10.3762/bjnano.11.11
- scaffold embedded with Ru(bpy)32+-conjugated silica nanoparticles. The DNA tetrahedron geometry acted as a capture DNA that repelled the nonspecific DNA entanglement along the ECL platform and stimulated the hybridization of glucose oxidase (GOD) enzyme-conjugated DNA (GOD-S). In a programmable cyclic
The effect of heat treatment on the morphology and mobility of Au nanoparticles
Beilstein J. Nanotechnol. 2020, 11, 61–67, doi:10.3762/bjnano.11.6
- manipulated on a silica substrate with an atomic force microscope (AFM) in tapping mode. Initially, the NPs were immovable by AFM energy dissipation. However, annealed NPs became movable, and less energy was required to displace the NPs annealed at higher temperature. However, after annealing at 800 °C, the
Advanced hybrid nanomaterials
Beilstein J. Nanotechnol. 2019, 10, 2563–2567, doi:10.3762/bjnano.10.247
- yield diverse materials, which were found to depend on the P/Ti atom ratio [20]. The ratio was found to determine the particle size and the aggregation state and thereby could strongly tune the porosity of the resulting materials. Colloidal chemistry with patchy silica nanoparticles was employed to
- (ethylene oxide)-b-poly(acrylic acid) (PEO-b-PAA) and an oligo-chitosan-type polyamine was used as a structure-directing agent to prepare ordered mesoporous silica materials in the work “pH-mediated control over the mesostructure of ordered mesoporous materials templated by polyion complex micelles” [22
- for sensing or corrosion protection. To understand composite formation of a complex hybrid assembly, high quality characterization is paramount. An example is small angle X-ray scattering (SAXS), which was used in the work “Mechanism of silica–lysozyme composite formation unraveled by in situ fast
Mobility of charge carriers in self-assembled monolayers
Beilstein J. Nanotechnol. 2019, 10, 2449–2458, doi:10.3762/bjnano.10.235
- aqueous NH4Cl solution was added and the product extracted with dichloromethane. The extract was filtered through a pad of silica, evaporated to dryness and recrystallized from methylcyclohexane, yielding 9.1 g (85%) of a yellow solid. 1H NMR (CDCl3, 400 MHz) δ 8.22 (s, 1H, H-10), 8.20 (s, 1H, H-9), 8.02
- solution (1.0 mol/L in THF, 12 mmol) were added dropwise. Stirring at room temperature was continued for 1 h and then 50 mL of H2O were added. The product was extracted with dichloromethane and filtered through a plug of silica. Evaporation of the volatiles resulted in 2 g of a brownish solid (90%). 1H NMR
- 24 h stirring at room temperature, the mixture was adsorbed onto silica and dried by means of a rotary evaporator. The loaded silica was placed on top of a silica plug and then eluted first with hexanes/dichloromethane 2:1 to remove nonpolar impurities. Then the product was eluted first by
Coating of upconversion nanoparticles with silica nanoshells of 5–250 nm thickness
Beilstein J. Nanotechnol. 2019, 10, 2410–2421, doi:10.3762/bjnano.10.231
- , D-12489 Berlin, Germany Hochschule Darmstadt - University of Applied Sciences, Fachbereich Chemie- und Biotechnologie, Stephanstr. 7, D-64295 Darmstadt, Germany 10.3762/bjnano.10.231 Abstract A concept for the growth of silica shells with a thickness of 5–250 nm onto oleate-coated NaYF4:Yb3+/Er3
- remain constant. Hence, the number of micelles stays constant, and their size is increased to accommodate the growing core–shell particles. Consequently, the formation of core-free silica particles is suppressed. When the negative zeta potential of the particles, which continuously decreased during the
- -core particles are obtained. This strategy can be easily transferred to other nanomaterials for the design of plasmonic nanoconstructs and sensor systems. Keywords: reverse microemulsion; silica coating; stepwise growth; thick shells; upconversion nanoparticles; Introduction Lanthanide-based
Targeted therapeutic effect against the breast cancer cell line MCF-7 with a CuFe2O4/silica/cisplatin nanocomposite formulation
Beilstein J. Nanotechnol. 2019, 10, 2217–2228, doi:10.3762/bjnano.10.214
- Chemistry, School of Basic Sciences, Vels Institute of Science, Technology and Advanced Studies (VISTAS), Chennai 600117, India 10.3762/bjnano.10.214 Abstract The combination of magnetic nanoparticles with a porous silica is a composite that has attracted significant attention for potential multifunctional
- theranostic applications. In this study, 30 wt % CuFe2O4 was impregnated into a matrix of monodispersed spherical hydrophilic silica (HYPS) nanoparticles through a simple dry impregnation technique. The chemotherapy drug cisplatin was loaded through electrostatic equilibrium adsorption over 24 h in normal
- dispersive X-ray (EDX) mapping analysis showed the presence of homogeneous silica particles with nanoclusters of copper ferrite distributed on the HYPS support. Vibrating sample magnetometry (VSM) analysis of CuFe2O4/HYPS showed paramagnetic behavior with a saturated magnetization value of 7.65 emu/g. DRS UV
Mannosylated brush copolymers based on poly(ethylene glycol) and poly(ε-caprolactone) as multivalent lectin-binding nanomaterials
Beilstein J. Nanotechnol. 2019, 10, 2192–2206, doi:10.3762/bjnano.10.212
- use; THF used for click reaction was dried over Na/benzophenone and freshly distilled. Thin-layer chromatography (TLC) was performed on Silica Gel 60 F254 plates (Merck) with UV detection (254 and 365 nm) or using appropriate developing solutions. Flash column chromatography was performed on silica
BergaCare SmartLipids: commercial lipophilic active concentrates for improved performance of dermal products
Beilstein J. Nanotechnol. 2019, 10, 2152–2162, doi:10.3762/bjnano.10.208
- carrier systems, but only with limited increase in stability. Stabilities reported were 20% after ten days in liposomes [18], 40% after 24 h in a nanoemulsion [19], 50% after 24 h in zein colloidal particles [19] and 60% after one month in a nanoemulsion stabilized by silica [20]. A screening was
Nitrogen-vacancy centers in diamond for nanoscale magnetic resonance imaging applications
Beilstein J. Nanotechnol. 2019, 10, 2128–2151, doi:10.3762/bjnano.10.207
- modulated with a magnetic field giving increased sensitivity. As bioimaging probes, they are versatile, cost-effective and easily functionalized, in addition to being easy to coat with silica for biomedical applications. Background-free imaging, both in vivo and in vitro, is achieved by applying an
Ion mobility and material transport on KBr in air as a function of the relative humidity
Beilstein J. Nanotechnol. 2019, 10, 2084–2093, doi:10.3762/bjnano.10.203
- drying effect of silica gel. With this setup, RH values below 2% can be obtained. The desired humidity can be reached within a time scale ranging from some minutes up to a few hours. Without active influence the air humidity remains quite constant with a maximum rate of change of less than one percent
Synthesis of highly active ETS-10-based titanosilicate for heterogeneously catalyzed transesterification of triglycerides
Beilstein J. Nanotechnol. 2019, 10, 2039–2061, doi:10.3762/bjnano.10.200
- removal [13]. Amongst the prospective solid catalysts designed for transesterification reactions, such as calcium [14] and other metal oxides [15], metal–organic frameworks (MOFs) [10], silica-supported catalysts [16], biochar [17] and other biomass-derived catalysts [18], zeolites and molecular sieves
- zero-field splitting (ZFS) parameter (D >> 10 GHz) and a ratio between rhombic and axial ZFS of 1/3. Such Fe(III) centers have been commonly observed in zeolite and silica materials and were assigned to iron sites with a distorted tetrahedral coordination geometry [56][57]. In addition, P-ETS-10/60
- 5 t. Afterwards, the pellets were ground and sieved in order to obtain fractions between 1.0 and 1.5 μm. Preparation of ETS-10-based catalysts ETS-10 molecular sieves were prepared by hydrothermal synthesis following a reported procedure [32]. Initially, a visually transparent silica-containing
Review of advanced sensor devices employing nanoarchitectonics concepts
Beilstein J. Nanotechnol. 2019, 10, 2014–2030, doi:10.3762/bjnano.10.198
- surface stress sensor as a novel nanomechanical device and a highly networked capsular nanoarchitecture of silica–porphyrin hybrid as the sensing material. Not limited to this particular case, innovations from both the device side and the materials side for improved sensors has been continuously pursued
Gold-coated plant virus as computed tomography imaging contrast agent
Beilstein J. Nanotechnol. 2019, 10, 1983–1993, doi:10.3762/bjnano.10.195
- AuNPs by generating 66 nm AuNPs coated with an 11 nm layer of silica and showed that for mice injected with these particles a contrast signal was observed [13]. Popovtzer et al. reported successful CT imaging of squamous cell carcinoma using gold nanorods coated with anti-antigen A9 [24]. The low
Porous silver-coated pNIPAM-co-AAc hydrogel nanocapsules
Beilstein J. Nanotechnol. 2019, 10, 1973–1982, doi:10.3762/bjnano.10.194
- enhanced extinction compared to molecular chromophores [44][45]. This type of particle generally consists of a single metal or an alloy shell with or without a dielectric silica core [46][47][48]. Fortunately, for biological applications, the optical properties of the nanoshells can be tuned by varying the
Synthesis and potent cytotoxic activity of a novel diosgenin derivative and its phytosomes against lung cancer cells
Beilstein J. Nanotechnol. 2019, 10, 1933–1942, doi:10.3762/bjnano.10.189
- used without further purification. Preparative column chromatography was performed using silica gel 60 with particle size 0.063–0.200 mm (70–230 mesh, Flash). Analytical thin-layer chromatography (TLC) was carried out employing silica gel 60 F254 plates (Merck, Darmstadt). Nuclear magnetic resonance
- mL) and extracted with H2O (20 mL). The combined organic layers were washed with saturated brine, dried over anhydrous Na2SO4, filtered, which was purified by silica gel chromatography (PE/EtOAc 4:1) to give the desired product (348 mg, 38%) as a white solid. TLC: Rf = 0.54 (PE/EtOAc 2:1). 1H NMR
Engineered superparamagnetic iron oxide nanoparticles (SPIONs) for dual-modality imaging of intracranial glioblastoma via EGFRvIII targeting
Beilstein J. Nanotechnol. 2019, 10, 1860–1872, doi:10.3762/bjnano.10.181
- -functionalized iron oxide nanoparticles after convection-enhanced delivery (CED) [35]. Lee and co-workers also showed that combining MRI with fluorescent imaging by using fluorescent silica-coated iron oxide nanoparticles has potential application in GBM treatment for improved intraoperative staging and enhanced
- for molecular imaging. A nanoprobe for the multimodal imaging of EGFRvIII overexpression in glioblastoma was constructed in the study. Compared with the EGFRvIII-antibody-functionalized iron oxide nanoparticles after convection-enhanced delivery (CED) to target EGFRvIII [35] and fluorescent-silica
Nanoarchitectonics meets cell surface engineering: shape recognition of human cells by halloysite-doped silica cell imprints
Beilstein J. Nanotechnol. 2019, 10, 1818–1825, doi:10.3762/bjnano.10.176
- practical manifestation of nanoarchitectonics, is a powerful tool to modify and enhance properties of live cells. In turn, cells may serve as sacrificial templates to fabricate cell-mimicking materials. Herein we report a facile method to produce cell-recognising silica imprints capable of the selective
- detection of human cells. We used HeLa cells to template silica inorganic shells doped with halloysite clay nanotubes. The shells were destroyed by sonication resulting in the formation of polydisperse hybrid imprints that were used to recognise HeLa cells in liquid media supplemented with yeast. We believe
- cells templates offer other fascinating opportunities due to their cell-mimicking geometries, for example, a novel class of bioinspired colloid particles was fabricated recently. Colloid antibodies were produced via the formation of solid silica shells doped with gold nanoparticles on bacterial cells
Layered double hydroxide/sepiolite hybrid nanoarchitectures for the controlled release of herbicides
Beilstein J. Nanotechnol. 2019, 10, 1679–1690, doi:10.3762/bjnano.10.163
- double oxides” in the presence of diverse species, e.g., silica nanoparticles [32]. Nanoarchitectonic materials involving the growth of LDH nanoparticles in the presence of fibrous clay silicates were patented several years ago [33]. Direct co-assembly of already formed particles of each component does
Nanoporous smartPearls for dermal application – Identification of optimal silica types and a scalable production process as prerequisites for marketed products
Beilstein J. Nanotechnol. 2019, 10, 1666–1678, doi:10.3762/bjnano.10.162
- Berlin, Germany Institute of Functional Interfaces, Karlsruher Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany 10.3762/bjnano.10.162 Abstract smartPearls are a dermal delivery system for poorly soluble active agents, consisting of nanoporous silica
- particles loaded with a long-term stable, amorphous active agent in its mesopores (2–50 nm). The amorphous state of the active agent is known to increase dermal bioavailability. For use in marketed products, optimal silica types were identified from commercially available, regulatory accepted silica. In
- addition, a scalable production process was demonstrated. The loading of the particles was performed by applying the immersion–evaporation method. The antioxidant rutin was used as a model active agent and ethanol was applied as the solvent. Various silica particles (Syloid®, Davisil®) differing in
Chiral nanostructures self-assembled from nitrocinnamic amide amphiphiles: substituent and solvent effects
Beilstein J. Nanotechnol. 2019, 10, 1608–1617, doi:10.3762/bjnano.10.156
- characterized on a Bruker AVANCE III HD 500 machine. The gel and precipitate were cast onto single-crystal silica plates and then coated with a thin layer of Pt after drying to increase the contrast. After that, the morphology was observed with a Hitachi S-4800 FE-SEM operating at an accelerating voltage of 10
Development of a new hybrid approach combining AFM and SEM for the nanoparticle dimensional metrology
Beilstein J. Nanotechnol. 2019, 10, 1523–1536, doi:10.3762/bjnano.10.150
- exactly on the same set of NPs. In order to establish the proof-of-concept of this approach and assess the performance of both instruments, measurements were carried out on several samples of spherical silica NP populations ranging from 5 to 110 nm. The spherical nature of silica NPs imposes naturally the
- data processing from AFM and SEM measurements on nanoparticles. The comparison between both techniques had been carried out on a single silica NP population with few NPs measured. In this new paper, we propose to extend this strategy by combining AFM and SEM measurements for several silica NP
- population of spherical NPs is performed. We used silica (SiO2) nanoparticles that are supposed to have a spherical shape [13][14]. Indeed, the sphericity requires that the NP height is equal to the diameter measured in XY-plane (lateral diameters). In this manner, height measurements performed by AFM can be
Other Beilstein-Institut Open Science Activities
