Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Nanoelectromechanical resonator arrays for ultrafast, gas-phase chromatographic chemical analysis.

ABSTRACT: Miniaturized gas chromatography (GC) systems can provide fast, quantitative analysis of chemical vapors in an ultrasmall package. We describe a chemical sensor technology based on resonant nanoelectromechanical systems (NEMS) mass detectors that provides the speed, sensitivity, specificity, and size required by the microscale GC paradigm. Such NEMS sensors have demonstrated detection of subparts per billion (ppb) concentrations of a phosphonate analyte. By combining two channels of NEMS detection with an ultrafast GC front-end, chromatographic analysis of 13 chemicals was performed within a 5 s time window.

SUBMITTER: Li M

PROVIDER: S-EPMC3839305 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Nanoelectromechanical resonator arrays for ultrafast, gas-phase chromatographic chemical analysis.

Li Mo M Myers E B EB Tang H X HX Aldridge S J SJ McCaig H C HC Whiting J J JJ Simonson R J RJ Lewis N S NS Roukes M L ML

Nano letters 20101001 10

Miniaturized gas chromatography (GC) systems can provide fast, quantitative analysis of chemical vapors in an ultrasmall package. We describe a chemical sensor technology based on resonant nanoelectromechanical systems (NEMS) mass detectors that provides the speed, sensitivity, specificity, and size required by the microscale GC paradigm. Such NEMS sensors have demonstrated detection of subparts per billion (ppb) concentrations of a phosphonate analyte. By combining two channels of NEMS detectio ...[more]

PMID: 20795729

Similar Datasets

Large-scale integration of nanoelectromechanical systems for gas sensing applications.

Project description:We have developed arrays of nanomechanical systems (NEMS) by large-scale integration, comprising thousands of individual nanoresonators with densities of up to 6 million NEMS per square centimeter. The individual NEMS devices are electrically coupled using a combined series-parallel configuration that is extremely robust with respect to lithographical defects and mechanical or electrostatic-discharge damage. Given the large number of connected nanoresonators, the arrays are able to handle extremely high input powers (>1 W per array, corresponding to <1 mW per nanoresonator) without excessive heating or deterioration of resonance response. We demonstrate the utility of integrated NEMS arrays as high-performance chemical vapor sensors, detecting a part-per-billion concentration of a chemical warfare simulant within only a 2 s exposure period.

| S-EPMC3839335 | biostudies-literature

Amphiphilic Block Copolymer PCL-PEG-PCL as Stationary Phase for Capillary Gas Chromatographic Separations.

Project description:This work presents the first example of utilization of amphiphilic block copolymer PCL-PEG-PCL as a stationary phase for capillary gas chromatographic (GC) separations. The PCL-PEG-PCL capillary column fabricated by static coating provides a high column efficiency of 3951 plates/m for n-dodecane at 120 °C. McReynolds constants and Abraham system constants were also determined in order to evaluate the polarity and possible molecular interactions of the PCL-PEG-PCL stationary phase. Its selectivity and resolving capability were investigated by using a complex mixture covering analytes of diverse types and positional, structural, and cis-/trans-isomers. Impressively, it exhibits high resolution performance for aliphatic and aromatic isomers with diverse polarity, including those critical isomers such as butanol, dichlorobenzene, dimethylnaphthalene, xylenol, dichlorobenzaldehyde, and toluidine. Moreover, it was applied for the determination of isomer impurities in real samples, suggesting its potential for practical use. The superior separation performance demonstrates the potential of PCL-PEG-PCL and related block copolymers as stationary phases in GC and other separation technologies.

| S-EPMC6749289 | biostudies-literature

Gas Chromatographic Fingerprint Analysis for the Comparison of Seized Cannabis Samples.

Project description:Cannabis sativa L. is widely used as recreational illegal drugs. Illicit Cannabis profiling, comparing seized samples, is challenging due to natural Cannabis heterogeneity. The aim of this study was to use GC-FID and GC-MS herbal fingerprints for intra (within)- and inter (between)-location variability evaluation. This study focused on finding an acceptable threshold to link seized samples. Through Pearson correlation-coefficient calculations between intra-location samples, 'linked' thresholds were derived using 95% and 99% confidence limits. False negative (FN) and false positive (FP) error rate calculations, aiming at obtaining the lowest possible FP value, were performed for different data pre-treatments. Fingerprint-alignment parameters were optimized using Automated Correlation-Optimized Warping (ACOW) or Design of Experiments (DoE), which presented similar results. Hence, ACOW data, as reference, showed 54% and 65% FP values (95 and 99% confidence, respectively). An additional fourth root normalization pre-treatment provided the best results for both the GC-FID and GC-MS datasets. For GC-FID, which showed the best improved FP error rate, 54 and 65% FP for the reference data decreased to 24 and 32%, respectively, after fourth root transformation. Cross-validation showed FP values similar as the entire calibration set, indicating the representativeness of the thresholds. A noteworthy improvement in discrimination between seized Cannabis samples could be concluded.

| S-EPMC8587667 | biostudies-literature

Tunable rainbow light trapping in ultrathin resonator arrays.

Project description:Rainbow light trapping in plasmonic devices allows for field enhancement of multiple wavelengths within a single device. However, many of these devices lack precise control over spatial and spectral enhancement profiles and cannot provide extremely high localised field strengths. Here we present a versatile, analytical design paradigm for rainbow trapping in nanogroove arrays by utilising both the groove-width and groove-length as tuning parameters. We couple this design technique with fabrication through multilayer thin-film deposition and focused ion beam milling, which enables the realisation of unprecedented feature sizes down to 5 nm and corresponding extreme normalised local field enhancements up to 103. We demonstrate rainbow trapping within the devices through hyperspectral microscopy and show agreement between the experimental results and simulation. The combination of expeditious design and precise fabrication underpins the implementation of these nanogroove arrays for manifold applications in sensing and nanoscale optics.

| S-EPMC7693327 | biostudies-literature

Bottom-up assembly of large-area nanowire resonator arrays.

Project description:Directed-assembly of nanowire-based devices will enable the development of integrated circuits with new functions that extend well beyond mainstream digital logic. For example, nanoelectromechanical resonators are very attractive for chip-based sensor arrays because of their potential for ultrasensitive mass detection. In this letter, we introduce a new bottom-up assembly method to fabricate large-area nanoelectromechanical arrays each having over 2,000 single-nanowire resonators. The nanowires are synthesized and chemically functionalized before they are integrated onto a silicon chip at predetermined locations. Peptide nucleic acid probe molecules attached to the nanowires before assembly maintain their binding selectivity and recognize complementary oligonucleotide targets once the resonator array is assembled. The two types of cantilevered resonators we integrated here using silicon and rhodium nanowires had Q-factors of approximately 4,500 and approximately 1,150, respectively, in vacuum. Taken together, these results show that bottom-up nanowire assembly can offer a practical alternative to top-down fabrication for sensitive chip-based detection.

| S-EPMC2656674 | biostudies-literature

New resonator geometries for ICE decoupling of loop arrays.

Project description:RF arrays with a large number of independent coil elements are advantageous for parallel transmission (pTx) and reception at high fields. One of the main challenges in designing RF arrays is to minimize the electromagnetic (EM) coupling between the coil elements. The induced current elimination (ICE) method, which uses additional resonator elements to cancel coils' mutual EM coupling, has proven to be a simple and efficient solution for decoupling microstrip, L/C loop, monopole and dipole arrays. However, in previous embodiments of conventional ICE decoupling, the decoupling elements acted as "magnetic-walls" with low transmit fields and consequently low MR signal near them. To solve this problem, new resonator geometries including overlapped and perpendicular decoupling loops are proposed. The new geometries were analyzed theoretically and validated in EM simulations, bench tests and MR experiments. The isolation between two closely-placed loops could be improved from about -5dB to <-45dB by using the new geometries.

| S-EPMC5389865 | biostudies-literature

Gas chromatographic separation of methoxylated polychlorinated biphenyl atropisomers.

Project description:Several polychlorinated biphenyls (PCBs) and their hydroxylated metabolites display axial chirality. Here we describe an enantioselective, gas chromatographic separation of methylated derivatives of hydroxylated (OH-)PCB atropisomers (MeO-PCB) using a chemically bonded beta-cyclodextrin column (Chirasil-Dex). The atropisomers of several MeO-PCBs could be separated on this column with resolutions ranging from 0.42 to 0.87 under isothermal or temperature-programmed conditions. In addition, the enantiomeric fraction of OH-PCB 136 metabolites was determined in male and female rats treated with racemic PCB 136. The methylated derivatives of two OH-PCB 136 metabolites showed an enantiomeric enrichment in liver tissue, whereas PCB 136 itself was near racemic.

| S-EPMC2579784 | biostudies-literature

Improved detection of tryptic immunoglobulin variable region peptides by chromatographic and gas-phase fractionation techniques.

Project description:Circulating antibodies provide valuable information about an individual’s immune status and constitute a significant portion of the human plasma proteome. Proteomic analysis of plasma is challenged by the large dynamic concentration range of plasma proteins, including antibodies. Peptide fractionation prior to data-independent (shotgun) proteomics has the potential to overcome this obstacle and enable increased coverage of plasma proteins. In this work, we evaluated the detection of tryptic immunoglobulin variable region peptides using multidimensional chromatography (high-pH preparative LC) or gas-phase ion mobility spectrometry (FAIMS). Typical digests of eight serum samples were obtained by (a) direct LC-MS (without prior fractionation, 1D), (b) LC-FAIMS-MS, and (c) high-pH reversed-phase fractionation into 24 fractions and subsequent measurement of each fraction. As de novo search is an essential step in antibody variable region peptide identification, all MS/MS spectra were acquired in high resolution Orbitrap mode.

2024-08-09 | PXD046072 | Pride

Gas Phase Chemical Evolution of Uranium, Aluminum, and Iron Oxides.

Project description:We use a recently developed plasma-flow reactor to experimentally investigate the formation of oxide nanoparticles from gas phase metal atoms during oxidation, homogeneous nucleation, condensation, and agglomeration processes. Gas phase uranium, aluminum, and iron atoms were cooled from 5000?K to 1000?K over short-time scales (?t?<?30?ms) at atmospheric pressures in the presence of excess oxygen. In-situ emission spectroscopy is used to measure the variation in monoxide/atomic emission intensity ratios as a function of temperature and oxygen fugacity. Condensed oxide nanoparticles are collected inside the reactor for ex-situ analyses using scanning and transmission electron microscopy (SEM, TEM) to determine their structural compositions and sizes. A chemical kinetics model is also developed to describe the gas phase reactions of iron and aluminum metals. The resulting sizes and forms of the crystalline nanoparticles (FeO-wustite, eta-Al2O3, UO2, and alpha-UO3) depend on the thermodynamic properties, kinetically-limited gas phase chemical reactions, and local redox conditions. This work shows the nucleation and growth of metal oxide particles in rapidly-cooling gas is closely coupled to the kinetically-controlled chemical pathways for vapor-phase oxide formation.

| S-EPMC6041320 | biostudies-literature

Fusion of Renewable Ring Resonator Lasers and Ultrafast Laser Inscribed Photonic Waveguides.

Project description:We demonstrated the monolithic integration of reusable and wavelength reconfigurable ring resonator lasers and waveguides of arbitrary shapes to out-couple and guide laser emission on the same fused-silica chip. The ring resonator hosts were patterned by a single-mask standard lithography, whereas the waveguides were inscribed in the proximity of the ring resonator by using 3-dimensional femtosecond laser inscription technology. Reusability of the integrated ring resonator - waveguide system was examined by depositing, removing, and re-depositing dye-doped SU-8 solid polymer, SU-8 liquid polymer, and liquid solvent (toluene). The wavelength reconfigurability was validated by employing Rhodamine 6G (R6G) and 3,3'-Diethyloxacarbocyanine iodide (CY3) as exemplary gain media. In all above cases, the waveguide was able to couple out and guide the laser emission. This work opens a door to reconfigurable active and passive photonic devices for on-chip coherent light sources, optical signal processing, and the investigation of new optical phenomena.

| S-EPMC5013411 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

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