Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Composite block polymer-microfabricated silicon nanoporous membrane.

ABSTRACT: Block polymers offer an attractive route to densely packed, monodisperse nanoscale pores. However, their fragility as thin films complicates their use as membranes. By integrating a block polymer film with a thin (100 microm) silicon substrate, we have developed a composite membrane providing both nanoscale size exclusion and fast transport of small molecules. Here we describe the fabrication of this membrane, evaluate its mechanical integrity, and demonstrate its transport properties for model solutes of large and small molecular weight. The ability to block large molecules without hindering smaller ones, coupled with the potential for surface modification of the polymer and the microelectromechanical system style of support, makes this composite membrane an attractive candidate for interfacing implantable sensing and drug-delivery devices with biological hosts.

SUBMITTER: Nuxoll EE

PROVIDER: S-EPMC2772169 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Composite block polymer-microfabricated silicon nanoporous membrane.

Nuxoll Eric E EE Hillmyer Marc A MA Wang Ruifang R Leighton C C Siegel Ronald A RA

ACS applied materials & interfaces 20090401 4

Block polymers offer an attractive route to densely packed, monodisperse nanoscale pores. However, their fragility as thin films complicates their use as membranes. By integrating a block polymer film with a thin (100 microm) silicon substrate, we have developed a composite membrane providing both nanoscale size exclusion and fast transport of small molecules. Here we describe the fabrication of this membrane, evaluate its mechanical integrity, and demonstrate its transport properties for model ...[more]

PMID: 20160882

Similar Datasets

Nanoporous organic polymer/cage composite membranes.

Project description: Not available

| S-EPMC3734621 | biostudies-literature

Ordered arrays of nanoporous silicon nanopillars and silicon nanopillars with nanoporous shells.

Project description:The fabrication of ordered arrays of nanoporous Si nanopillars with and without nanoporous base and ordered arrays of Si nanopillars with nanoporous shells are presented. The fabrication route is using a combination of substrate conformal imprint lithography and metal-assisted chemical etching. The metal-assisted chemical etching is performed in solutions with different [HF]/[H2O2 + HF] ratios. Both pore formation and polishing (marked by the vertical etching of the nanopillars) are observed in highly doped and lightly doped Si during metal-assisted chemical etching. Pore formation is more active in the highly doped Si, while the transition from polishing to pore formation is more obvious in the lightly doped Si. The etching rate is clearly higher in the highly doped Si. Oxidation occurs on the sidewalls of the pillars by etching in solutions with small [HF]/[H2O2 + HF] ratios, leading to thinning, bending, and bonding of pillars.

| S-EPMC3570473 | biostudies-literature

Carbon dot-polymer nanoporous membrane for recyclable sunlight-sterilized facemasks.

Project description:Facemasks are considered the most effective means for preventing infection and spread of viral particles. In particular, the coronavirus (COVID-19) pandemic underscores the urgent need for developing recyclable facemasks due to the considerable environmental damage and health risks imposed by disposable masks and respirators. We demonstrate synthesis of nanoporous membranes comprising carbon dots (C-dots) and poly(vinylidene fluoride) (PVDF), and demonstrate their potential use for recyclable, self-sterilized facemasks. Notably, the composite C-dot-PVDF films exhibit hydrophobic surface which prevents moisture accumulation and a compact nanopore network which allows both breathability as well as effective filtration of particles above 100 nm in diameter. Particularly important, self-sterilization occurs upon short solar irradiation of the membrane, as the embedded C-dots efficiently absorb visible light, concurrently giving rise to elevated temperatures through heat dissipation.

| S-EPMC7907754 | biostudies-literature

Superior Ionic Transferring Polymer with Silicon Dioxide Composite Membrane via Phase Inversion Method Designed for High Performance Sodium-Ion Battery.

Project description:Superior sodium-ion-conducting polymer poly(vinyledene fluoride)-silicon dioxide (PVdF-SiO2) composite separator membrane was prepared via simple phase inversion method, which is a suitable alternative conventional polypropylene membrane. Basically, PVdF is the promising for use as high porous polymer electrolyte membrane due to its high dielectric constant ( = 8.4). In this work, we prepared a composite membrane using PVdF-SiO2 via phase inversion method. This work was systematically studied towards the morphology, porosity, and electrochemical properties of as prepared membrane. The electrolyte uptake capability of separator membrane tested with 1 M NaPF6 electrolyte solution and temperature-dependent ionic conduction test were performed at various temperatures. This membrane exhibits higher ionic conductivity of 4.7 × 10-2 S cm-1 at room temperature. The physical properties were analyzed by X-ray diffraction, FT-IR, and FE-SEM micrographs analyses. The electrochemical performances with impedance analysis carried for prepared membrane with the as-prepared sodium P2-type cathode material. The material showed an initial discharge capacity of 178 mAh g-1 at 0.1 C between 2 and 4 V with 98% columbic efficiency and 81% capacity retention after 50 cycles upon using the as-prepared PVdF-SiO2 composite separator membrane.

| S-EPMC7077619 | biostudies-literature

Enhanced Thermal Conductivity of Polymer Composite by Adding Fishbone-like Silicon Carbide.

Project description:The rapid development of chip technology has all put forward higher requirements for highly thermally conductive materials. In this work, a new type of material of Fishbone-like silicon carbide (SiC) material was used as the filler in a polyvinylidene fluoride (PVDF) matrix. The silicon carbide/polyvinylidene fluoride (SiC/PVDF) composites were successfully prepared with different loading by a simple mixing method. The thermal conductivity of SiC/PVDF composite reached 0.92 W m-1 K-1, which is 470% higher than that of pure polymer. The results show that using the filler with a new structure to construct thermal conductivity networks is an effective way to improve the thermal conductivity of PVDF. This work provides a new idea for the further application in the field of electronic packaging.

| S-EPMC8620080 | biostudies-literature

Versatile ultrathin nanoporous silicon nitride membranes.

Project description:Single- and multiple-nanopore membranes are both highly interesting for biosensing and separation processes, as well as their ability to mimic biological membranes. The density of pores, their shape, and their surface chemistry are the key factors that determine membrane transport and separation capabilities. Here, we report silicon nitride (SiN) membranes with fully controlled porosity, pore geometry, and pore surface chemistry. An ultrathin freestanding SiN platform is described with conical or double-conical nanopores of diameters as small as several nanometers, prepared by the track-etching technique. This technique allows the membrane porosity to be tuned from one to billions of pores per square centimeter. We demonstrate the separation capabilities of these membranes by discrimination of dye and protein molecules based on their charge and size. This separation process is based on an electrostatic mechanism and operates in physiological electrolyte conditions. As we have also shown, the separation capabilities can be tuned by chemically modifying the pore walls. Compared with typical membranes with cylindrical pores, the conical and double-conical pores reported here allow for higher fluxes, a critical advantage in separation applications. In addition, the conical pore shape results in a shorter effective length, which gives advantages for single biomolecule detection applications such as nanopore-based DNA analysis.

| S-EPMC2795523 | biostudies-literature

A structure-permeability relationship of ultrathin nanoporous silicon membrane: a comparison with the nuclear envelope.

Project description:We report on a simple, quantitative relationship between structure and permeability of a novel ultrathin nanoporous membrane based on nanocrystalline silicon. Large permeability of the free-standing nanomembrane to Ru(NH3)63+, O2, or 1,1'-ferrocenedimethanol, which was able to be measured for the first time by employing scanning electrochemical microscopy, is proportional to the density (67 mum-2) and average radius (5.6 nm) of nanopores. As solution electrolyte concentration decreases down to 0.01 M, the nanopores are selectively "closed" against Fe(CN)64- because of electrostatic repulsion against negative charges at the pore wall. Permeability of the silicon nanomembrane was compared to permeability of the nuclear envelope to find that the channel diameter of the nuclear pore complex that perforates the nuclear envelope is much larger than the average diameter of the silicon nanopores and concomitantly a hypothetical diameter of 10 nm.

| S-EPMC3874290 | biostudies-literature

Photochemical functionalization of polymer surfaces for microfabricated devices.

Project description:Herein we report the topochemical modification of polymer surfaces with perfluorinated aromatic azides. The aryl azides, which have quaternary amine or aldehyde functional groups, were linked to the surface of the polymer by UV irradiation. The polymer substrates used in this study were cyclic olefin copolymer and poly(methyl methacrylate). These substrates were characterized before and after modification using reflection-absorption infrared spectroscopy, sessile water contact angle measurements, and X-ray photoelectron spectroscopy. Analysis of the surface confirmed the presence of aromatic groups with aldehyde or quaternary amine functionality. Enzyme immobilization and patterning onto polymer surfaces were studied using confocal microscopy. Enzymatic digests of protein were carried out on modified probes manufactured from thermoplastic substrates, and the resulting peptide analysis was completed using matrix-assisted laser desorption/ionization mass spectrometry. The use of functionalized perfluorinated aromatic azides allows the surface chemistry of thermoplastics to be tailored for specific lab-on-a-chip applications.

| S-EPMC3529600 | biostudies-literature

Bare Eye Detection of Bacterial Enzymes of <i>Pseudomonas aeruginosa</i> with Polymer Modified Nanoporous Silicon Rugate Filters.

Project description:The fabrication, characterization and application of a nanoporous Silicon Rugate Filter (pSiRF) loaded with an enzymatically degradable polymer is reported as a bare eye detection optical sensor for enzymes of pathogenic bacteria, which is devoid of any dyes. The nanopores of pSiRF were filled with poly(lactic acid) (PLA), which, upon enzymatic degradation, resulted in a change in the effective refractive index of the pSiRF film, leading to a readily discernible color change of the sensor. The shifts in the characteristic fringe patterns before and after the enzymatic reaction were analyzed quantitatively by Reflectometric Interference Spectroscopy (RIfS) to estimate the apparent kinetics and its dependence on enzyme concentration. A clear color change from green to blue was observed by the bare eye after PLA degradation by proteinase K. Moreover, the color change was further confirmed in measurements in bacterial suspensions of the pathogen Pseudomonas aeruginosa (PAO1) as well as in situ in the corresponding bacterial supernatants. This study highlights the potential of the approach in point of care bacteria detection.

| S-EPMC9776340 | biostudies-literature

Scale-dependent diffusion anisotropy in nanoporous silicon.

Project description:Nanoporous silicon produced by electrochemical etching of highly B-doped p-type silicon wafers can be prepared with tubular pores imbedded in a silicon matrix. Such materials have found many technological applications and provide a useful model system for studying phase transitions under confinement. This paper reports a joint experimental and simulation study of diffusion in such materials, covering displacements from molecular dimensions up to tens of micrometers with carefully selected probe molecules. In addition to mass transfer through the channels, diffusion (at much smaller rates) is also found to occur in directions perpendicular to the channels, thus providing clear evidence of connectivity. With increasing displacements, propagation in both axial and transversal directions is progressively retarded, suggesting a scale-dependent, hierarchical distribution of transport resistances ("constrictions" in the channels) and of shortcuts (connecting "bridges") between adjacent channels. The experimental evidence from these studies is confirmed by molecular dynamics (MD) simulation in the range of atomistic displacements and rationalized with a simple model of statistically distributed "constrictions" and "bridges" for displacements in the micrometer range via dynamic Monte Carlo (DMC) simulation. Both ranges are demonstrated to be mutually transferrable by DMC simulations based on the pore space topology determined by electron tomography.

| S-EPMC5247748 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data