Search results for: William F. Siems

Items from 1 to 20 out of 41 results

article

Construction and evaluation of a hermetically sealed accurate ion mobility instrument

Brian C. Hauck, William F. Siems, Charles S. Harden, Vincent M. McHugh, more

International Journal for Ion Mobility Spectrometry > 2017 > 20 > 3-4 > 57-66

Ion mobility spectrometry (IMS) is widely used to detect and identify chemical warfare agents, narcotics, and explosives in the field based on their reduced mobility (K₀) values. Current detection windows for these analytes can only be as narrow as ±2% of the K₀ values for the analyte being sought. These wide detection windows cause false positive alarms when an interferent with a similar reduced...

article

Accurate zero-field mobilities of atomic ions in the rare gases for calibration of ion mobility spectrometers

Larry A. Viehland, Tamar Skaist, Chetana Adhikari, William F. Siems

International Journal for Ion Mobility Spectrometry > 2017 > 20 > 1-2 > 1-9

The zero-field mobilities of many atomic ions in rare gases are calculated from highly accurate, ab initio potential energy curves. They are expected to be accurate to at least 0.05%, thus allowing them to be used to calibrate mobility measurements in different drift-tube and ion mobility mass spectrometers.

article

Multidimensional Separation of Natural Products Using Liquid Chromatography Coupled to Hadamard Transform Ion Mobility Mass Spectrometry

Wenjie Liu, Xing Zhang, Richard Knochenmuss, William F. Siems, more

Journal of The American Society for Mass Spectrometry > 2016 > 27 > 5 > 810-821

A high performance liquid chromatograph (HPLC)was interfaced to an atmospheric drift tube ion mobility time of flight mass spectrometry. The power of multidimensional separation was demonstrated using chili pepper extracts. The ambient pressure drift tube ion mobility provided high resolving powers up to 166 for the HPLC eluent. With implementation of Hadamard transform (HT), the duty cycle for the...

article

Rapid profiling and identification of anthocyanins in fruits with Hadamard transform ion mobility mass spectrometry

Wenjie Liu, Xing Zhang, William F. Siems, Herbert H. Hill, more

Food Chemistry > 2015 > 177 > Complete > 225-232

The use of Hadamard transform ion mobility mass spectrometry (HT-IMMS) in the profiling of anthocyanins from different fruits is presented. Samples extracted with acidic methanol and purified with solid phase extraction were analyzed with direct IMMS infusion. The separation of various anthocyanins was achieved within 30s with resolving powers up to 110. The ion mobility drift times correlated with...

article

Characterizing metabolic changes in human colorectal cancer

Michael D. Williams, Xing Zhang, Jeong-Jin Park, William F. Siems, more

Analytical and Bioanalytical Chemistry > 2015 > 407 > 16 > 4581-4595

Colorectal cancer (CRC) remains a leading cause of cancer death worldwide, despite the fact that it is a curable disease when diagnosed early. The development of new screening methods to aid in early diagnosis or identify precursor lesions at risk for progressing to CRC will be vital to improving the survival rate of individuals predisposed to CRC. Metabolomics is an advancing area that has recently...

article

Electrospray ionization-voltage sweep-Ion mobility spectrometry for biomolecules and complex samples

Eric J. Davis, Kristopher F. Grows, William F. Siems, Herbert H. Hill

International Journal for Ion Mobility Spectrometry > 2014 > 17 > 3-4 > 147-156

Voltage Sweep Ion Mobility Spectrometry (VSIMS) has been applied to complex samples using electrospray ionization (ESI). The usable range of VSIMS has been extended from that obtained in previous studies where only volatile compounds were investigated. Using ESI, VSIMS was evaluated with compounds with reduced mobility values as low as 0.3 V²cm⁻¹ s⁻¹. The primary advantage of VSIMS is to enable a...

article

Structure selective ion molecule interactions (SSIMI) in ion mobility spectrometry

Kristyn M. Roscioli, Manuja R. Lamabadusuriya, Charles S. Harden, Anthony J. Midey, more

International Journal for Ion Mobility Spectrometry > 2014 > 17 > 1 > 43-53

The overall objective of this project was to develop an analytical method that utilizes structure selective ion molecule interactions (SSIMI) in ion mobility spectrometry (IMS) to shift the mobility of a targeted analyte through the addition of a gas phase modifier to the buffer gas. IMS is a sensitive, rapid method for the detection of harmful chemicals; however false alarm responses do occur and...

article

Ion mobility mass spectrometry analysis of isomeric disaccharide precursor, product and cluster ions

Hongli Li, Brad Bendiak, William F. Siems, David R. Gang, more

Rapid Communications in Mass Spectrometry > 27 > 23 > 2699 - 2709

RATIONALECarbohydrates are highly variable in structure owing to differences in their anomeric configurations, monomer stereochemistry, inter‐residue linkage positions and general branching features. The separation of carbohydrate isomers poses a great challenge for current analytical techniques. METHODSThe isomeric heterogeneity of disaccharide ions and monosaccharide‐glycolaldehyde product ions...

article

Evaluation of ion mobility-mass spectrometry for determining the isomeric heterogeneity of oligosaccharide-alditols derived from bovine submaxillary mucin

Hongli Li, Brad Bendiak, Kimberly Kaplan, Eric Davis, more

International Journal of Mass Spectrometry > 2013 > 352 > Complete > 9-18

Rapid separation and independent analysis of isomeric species are needed for the structural characterization of carbohydrates in glycomics research. Ion mobility-mass spectrometry techniques were used to examine a series of isomeric neutral oligosaccharide-alditols derived from bovine submaxillary mucin. Several analytical techniques were employed: (1) off line separation of the oligosaccharide-alditol...

article

Real time pharmaceutical reaction monitoring by electrospray ion mobility-mass spectrometry

Kristyn M. Roscioli, Xing Zhang, Shelly X. Li, Gilles H. Goetz, more

International Journal of Mass Spectrometry > 2013 > 336 > Complete > 27-36

Reaction monitoring is a critical step in the synthesis of new drug entities, and many pharmaceutical companies spend significant resources on equipment and new methods to perform this task. The potential of electrospray ion mobility-mass spectrometry (ESI-IMMS) as a method for monitoring pharmaceutical reactions in real time is demonstrated with a reductive amination reaction that is commonly used...

article

Ion mobility-mass correlation trend line separation of glycoprotein digests without deglycosylation

Hongli Li, Brad Bendiak, William F. Siems, David R. Gang, more

International Journal for Ion Mobility Spectrometry > 2013 > 16 > 2 > 105-115

A high-throughput ion mobility mass spectrometer (IMMS) was used to rapidly separate and analyze peptides and glycopeptides derived from glycoproteins. Two glycoproteins, human α-1-acid glycoprotein and antithrombin III were digested with trypsin and subjected to electro-spray traveling wave IMMS analysis. No deglycosylation steps were performed; samples were complex mixtures of peptides and glycopeptides...

article

The novel analysis of uranyl compounds by electrospray-ion mobility-mass spectrometry

Christina L. Crawford, Glenn A. Fugate, Paula R. Cable-Dunlap, Nathalie A. Wall, more

International Journal of Mass Spectrometry > 2013 > 333 > Complete > 21-26

This study relates the first mass identification of mobility peaks associated with uranyl species. These uranyl species were introduced into the gas phase by electrospray ionization and detected by ion mobility-mass spectrometry (IM-MS) to obtain rapid chemical information from uranyl compounds. Uranyl compound analysis in nuclear forensic science is typically performed using alpha, gamma, and mass...

article

Neuronal metabolomics by ion mobility mass spectrometry: cocaine effects on glucose and selected biogenic amine metabolites in the frontal cortex, striatum, and thalamus of the rat

Kimberly A. Kaplan, Veronica M. Chiu, Peter A. Lukus, Xing Zhang, more

Analytical and Bioanalytical Chemistry > 2013 > 405 > 6 > 1959-1968

We report results of studies of global and targeted neuronal metabolomes by ambient pressure ion mobility mass spectrometry. The rat frontal cortex, striatum, and thalamus were sampled from control nontreated rats and those treated with acute cocaine or pargyline. Quantitative evaluations were made by standard additions or isotopic dilution. The mass detection limit was ∼100 pmol varying with the...

article

Uniform Moment Theory for Charged Particle Motion in Gases

Larry A. Viehland, William F. Siems

Journal of The American Society for Mass Spectrometry > 2012 > 23 > 11 > 1841-1854

Moment equations for the motion of trace amounts of charged particles through dilute gases are developed from the Boltzmann equation. A new method for truncating the coupled moment equations is used to develop differential equations governing the moments in successive approximations. The first approximation equations are shown to agree completely with equations known to describe ion motion in drift-tube...

article

Modular Ion Mobility Spectrometer for Explosives Detection Using Corona Ionization

Kristyn M. Roscioli, Eric Davis, William F. Siems, Adrian Mariano, more

Analytical Chemistry > 2011 > 83 > 15 > 5965 - 5971

article

Voltage Sweep Ion Mobility Spectrometry

Eric J. Davis, Michael D. Williams, William F. Siems, Herbert H. Hill

Analytical Chemistry > 2011 > 83 > 4 > 1260 - 1267

article

Comprehensive software suite for the operation, maintenance, and evaluation of an ion mobility spectrometer

Eric James Davis, Brian H. Clowers, William F. Siems, Herbert H. Hill

International Journal for Ion Mobility Spectrometry > 2011 > 14 > 2-3 > 117-124

Scientific applications of Ion Mobility Spectrometry require the ability to easily compare data between different laboratories. Reduced mobility values attempt to provide this functionality, but no standard exists for the collection and manipulation of the raw data obtained during an IMS experiment. We have created a comprehensive software suite based on the LabVIEW programming language that can be...

article

Metabolic profiling of Escherichia coli by ion mobility‐mass spectrometry with MALDI ion source

Prabha Dwivedi, Geoffery Puzon, Maggie Tam, Denis Langlais, more

Journal of Mass Spectrometry > 45 > 12 > 1383 - 1393

Comprehensive metabolome analysis using mass spectrometry (MS) often results in a complex mass spectrum and difficult data analysis resulting from the signals of numerous small molecules in the metabolome. In addition, MS alone has difficulty measuring isobars and chiral, conformational and structural isomers. When a matrix‐assisted laser desorption ionization (MALDI) source is added, the difficulty...

article

Analysis of Black Powder by Ion Mobility−Time-of-Flight Mass Spectrometry

Christina L. Crawford, Hacene Boudries, Ralph J. Reda, Kristyn M. Roscioli, more

Analytical Chemistry > 2010 > 82 > 1 > 387 - 393

article

Pathways of Water Oxidation Catalyzed by Ruthenium “Blue Dimers” Characterized by ¹⁸ O-Isotopic Labeling

Jonathan L. Cape, William F. Siems, James K. Hurst

Inorganic Chemistry > 2009 > 48 > 18 > 8729 - 8735

Publication date

Set your own date range

Content availability

Available (40)
None (1)

Keywords

ION MOBILITY SPECTROMETRY (4)
ESI (3)
IMS (3)
ION MOBILITY MASS SPECTROMETRY (3)
ELECTROSPRAY IONIZATION (2)
HADAMARD TRANSFORM (2)
METABOLOMICS (2)
PEAK CAPACITY (2)
AB INITIO POTENTIALS (1)
ACCURACY (1)
ANTHOCYANIN (1)
BACE (1)
BIOANALYTICAL METHODS (1)
BITTERNESS (1)
BOLTZMANN EQUATION (1)
BOVINE SUBMAXILLARY MUCIN (1)
CALCIUM SENSITIVITY (1)
CALIBRATION (1)
CANCER BIOMARKERS (1)
CHILI PEPPER (1)
COCAINE (1)
COLLISION INDUCED DISSOCIATION (1)
COLORECTAL CANCER (1)
DIFFERENTIAL MOBILITY SPECTROMETERS (1)
DRIFT GAS MODIFIERS (1)
DRIFT-TUBE MASS SPECTROMETERS (1)
DTIMS (1)
ELECTRON MOBILITY (1)
ELECTROSPRAY (1)
ESCHERICHIA COLI (1)
ESI-IMS (1)
ESI-VSIMS (1)
EUPHORBIACEAE (1)
FALSE ALARM RATES (1)
FALSE ALARMS (1)
FORENSICS (1)
FOURIER TRANSFORM SPECTROSCOPY (1)
FRANK–STARLING RELATION (1)
GASEOUS ION MOBILITY (1)
GASEOUS ION TRANSPORT (1)
GLUCOSE (1)
GLYCOPEPTIDES (1)
GLYCOPROTEIN (1)
HERMETICALLY SEALED (1)
HEVEA BRASILIENSIS (1)
HPLC (1)
INTRACELLULAR PEPTIDASE (1)
ION CYCLOTRON RESONANCE (1)
ION MOBILITY (1)
ION MOBILITY MASS SPECTROMETRY (IMMS) (1)
ION MOBILITY SPECTROMETERS (1)
ION MOBILITY-MASS SPECTROMETRY (1)
ION MOBILITY‐MASS SPECTROMETRY (1)
ION TRAPS (1)
ISOMERIC HETEROGENEITY (1)
ISOTOPE DILUTION (1)
LABVIEW (1)
MALDI (1)
MALDI-TOF (1)
MASS SPECTROMETRY (1)
MASS SPECTROMETRY ICP-MS (1)
MATRIX-ASSISTED LASER DESORPTION/IONIZATION (1)
MOBILITY SELECTED FRAGMENTATION (1)
MOBILITY SHIFTS (1)
MOBILITY-MASS RELATIONSHIP (1)
MOBILITY-MASS TREND LINE SEPARATION (1)
MS (1)
MULTIDIMENSIONAL PROTEIN PROFILING (1)
MYOSIN REGULATORY LIGHT CHAIN (1)
OLIGOSACCHARIDE-ALDITOL (1)
PASSIVE MUSCLE STRETCH (1)
PEPTIDES (1)
PHARMACEUTICALS (1)
PLANT DEFENSE (1)
POST-TRANSLATIONAL MODIFICATION (1)
PRECISION (1)
PROTEINASE ISOINHIBITORS (1)
REACTION MONITORING: REDUCTIVE AMINATION REACTIONS (1)
RESOLUTION (1)
RESOLVING POWER (1)
SAX (1)
SDS-PAGE (1)
SOFTWARE (1)
STANDARD ADDITION (1)
TEMPERATURE-DEPENDENT ION MOBILITY (1)
TOF-MS (1)
TRAVELING WAVE ION MOBILITY MASS SPECTROMETRY (1)
URANYL (1)
VOLTAGE SWEEP (1)
VOLTAGE-SWEEP (1)
VSIMS (1)
WOUNDING (1)
Β-CN F193-209 (1)
more

Data set

ACS (14)
Springer (13)
Elsevier (12)
Wiley (2)

Journal

Analytical Chemistry (8)
International Journal for Ion Mobility Spectrometry (6)
Journal of The American Society for Mass Spectrometry (5)
International Journal of Mass Spectrometry (3)
Journal of the American Society for Mass Spectrometry (3)
Analytical and Bioanalytical Chemistry (2)
Biochemistry (2)
Analytica Chimica Acta (1)
Archives of Biochemistry and Biophysics (1)
Food Chemistry (1)
Inorganic Chemistry (1)
Journal of Agricultural and Food Chemistry (1)
Journal of Chromatography B (1)
Journal of Mass Spectrometry (1)
Journal of the American Chemical Society (1)
LWT - Food Science and Technology (1)
Organometallics (1)
Phytochemistry (1)
Rapid Communications in Mass Spectrometry (1)
more

INFONA - science communication portal

Search results for: William F. Siems

Construction and evaluation of a hermetically sealed accurate ion mobility instrument

Accurate zero-field mobilities of atomic ions in the rare gases for calibration of ion mobility spectrometers

Multidimensional Separation of Natural Products Using Liquid Chromatography Coupled to Hadamard Transform Ion Mobility Mass Spectrometry

Rapid profiling and identification of anthocyanins in fruits with Hadamard transform ion mobility mass spectrometry

Characterizing metabolic changes in human colorectal cancer

Electrospray ionization-voltage sweep-Ion mobility spectrometry for biomolecules and complex samples

Structure selective ion molecule interactions (SSIMI) in ion mobility spectrometry

Ion mobility mass spectrometry analysis of isomeric disaccharide precursor, product and cluster ions

Evaluation of ion mobility-mass spectrometry for determining the isomeric heterogeneity of oligosaccharide-alditols derived from bovine submaxillary mucin

Real time pharmaceutical reaction monitoring by electrospray ion mobility-mass spectrometry

Ion mobility-mass correlation trend line separation of glycoprotein digests without deglycosylation

The novel analysis of uranyl compounds by electrospray-ion mobility-mass spectrometry

Neuronal metabolomics by ion mobility mass spectrometry: cocaine effects on glucose and selected biogenic amine metabolites in the frontal cortex, striatum, and thalamus of the rat

Uniform Moment Theory for Charged Particle Motion in Gases

Modular Ion Mobility Spectrometer for Explosives Detection Using Corona Ionization

Voltage Sweep Ion Mobility Spectrometry

Comprehensive software suite for the operation, maintenance, and evaluation of an ion mobility spectrometer

Metabolic profiling of Escherichia coli by ion mobility‐mass spectrometry with MALDI ion source

Analysis of Black Powder by Ion Mobility−Time-of-Flight Mass Spectrometry

Pathways of Water Oxidation Catalyzed by Ruthenium “Blue Dimers” Characterized by ¹⁸ O-Isotopic Labeling

Filter options

Publication date

Content availability

Keywords

Data set

Journal

INFONA - science communication portal

Search results for: William F. Siems

Add recipient

Sending message cancelled

Are you sure you want to cancel sending this message?

Send message

Filter options

Publication date

Date range setting

Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.

Content availability

Keywords

Data set

Journal

Reporting an error / abuse

Sending the report failed

Accessibility options