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Recent Advances in Ambient Mass Spectrometry of Trace Explosives

May 6, 2018

Author(s)

Thomas Forbes, Edward Sisco

Ambient mass spectrometry has evolved rapidly over the past decade, yielding a plethora of platforms and demonstrating scientific advancements across a range of fields from biological imaging to rapid quality control. These techniques have enabled real

Determining the chemical-heterogeneity-corrected molar mass averages and distribution of poly(styrene-co-t-butyl methacrylate) using SEC/MALS/UV/DRI

May 1, 2018

Author(s)

Andre M. Striegel, Imad Haidar Ahmad

Chemical heterogeneity, defined as the change (or lack thereof) across the molar mass distribution (MMD) in the monomeric ratio of a copolymer, can influence processing and end-use properties such as solubility, gas permeation, conductivity, and the energy

NIST Spectroscopic Measurement Standards

May 1, 2018

Author(s)

Paul C. DeRose, Kenneth D. Cole, Aaron Urbas, Steven J. Choquette, Evelyn Solis, Erica V. Stein, John E. Schiel, Brian Lang, Hua-Jun He

Ultraviolet (UV) absorbance measurements provide a rapid and reliable method to determine protein concentrations. The National Institute of Standards and Technology (NIST) has developed Standard Reference Material (SRM) 2082as a pathlength standard for UV

Development of a high-resolution laser absorption spectroscopy method with application to the determination of absolute concentration of gaseous elemental mercury in air

April 30, 2018

Author(s)

Abneesh Srivastava, Joseph T. Hodges

Isotope dilution cold-vapor inductively coupled plasma mass spectrometry (ID-CV-ICPMS) has become the primary standard for measurement of gaseous elemental mercury (GEM) mass concentration. However, quantitative mass spectrometry is challenging for several

Detection of Nonvolatile Inorganic Oxidizer-Based Explosives from Wipe Collections by Infrared Thermal Desorption-Direct Analysis in Real Time Mass Spectrometry

April 27, 2018

Author(s)

Thomas Forbes, Edward Sisco, Matthew Staymates

Infrared thermal desorption (IRTD) was coupled with direct analysis in real time mass spectrometry (DART-MS) for the detection of both inorganic and organic explosives from wipe collected samples. This platform generated discrete and rapid heating rates

The role of mass spectrometry in the characterization of biologic protein products

April 25, 2018

Author(s)

Deepali Rathore, John E. Schiel, Anneliese Faustino, Eric Pang, Michael Boyne, Sarah M. Rogstad

Introduction: Mass spectrometry (MS) is widely used in the characterization of biomolecules including peptide and protein therapeutics. These biotechnology products have seen rapid growth over the past few decades and continue to dominate the global

High temperature performance of the HITEMP2010 and HITRAN Online databases: comparison with frequency comb measurements of water vapor absorption from 6800 cm-1 to 7200 cm-1

April 3, 2018

Author(s)

Paul J. Schroeder, D Pfotenhauer, J Yang, William C. Swann, Ian R. Coddington, Nathan R. Newbury, Greg B. Rieker

The HITEMP2010 and HITRAN Online databases are important tools for predicting molecular absorption under various environmental conditions. At room temperature the databases can be quite accurate, owing to their development using room temperature absorption

Submultiple Data Collection to Explore Spectroscopic Instrument Instabilities Shows that Much of the "Noise" is not Stochastic

April 3, 2018

Author(s)

Curtis W. Meuse, James J. Filliben, Kenneth A. Rubinson

As has long been understood, the noise on a spectrometric signal can be reduced by averaging over time, and the averaged noise is expected to decrease as t1/2, the square root of the data collection time. However, with contemporary capability for fast data

Perfluorinated Alkyl Acids and Fecundity Assessment in Striped mullet (Mugil cephalus) at Merritt Island National Wildlife Refuge

April 1, 2018

Author(s)

John Bowden, Jacqueline T. Bangma, Jessica L. Reiner, Russell H. Lowers, Theresa M. Cantu, Jacob Scott, Jeffery Korte, Douglas M. Scheidt, Chris McDonough, Jonathan Tucker, Eric Reyier, Douglas H. Adams, Bonnie Ahr, Brenton Back

This study investigated wild caught Striped mullet (Mugil cephalus) at Merritt Island National Wildlife Refuge (MINWR) for levels of 15 perfluoroalkyl acids (PFAAs) in tandem with fecundity measurements (n = 42) and oocyte developmental stages (n = 128)

NIST Lipidomics Workflow Questionnaire: An Assessment of Community-Wide Methodologies and Perspectives

March 20, 2018

Author(s)

John Bowden, Candice Z. Ulmer, Christina M. Jones, Jeremy P. Koelmel, Richard A. Yost

Introduction Efforts to harmonize lipidomic methodologies have been limited within the community. Here, we aimed to capitalize on the recent NIST lipidomics interlaboratory comparison exercise by implementing a questionnaire that assessed current

Performance and failure modes of Si anodes patterned with thin-film Ni catalyst islands for water oxidation

March 6, 2018

Author(s)

Ke Sun, Nicole L. Ritzert, Jimmy John, Haiyan Tan, William G. Hale, Jingjing Jiang, Kimberly M. Papadantonakis, Thomas P. Moffat, Bruce S. Brunschwig, Nathan S. Lewis

Silicon photoanodes patterned with Ni thin film catalyst islands exhibited stable oxygen evolution for over 240 h of continuous operation in 1.0 mol L-1 KOH(aq) under simulated sunlight conditions. Buried-junction np+-Si(111) photoanodes with an 18.0%

Stepwise extraction, chemical modification, GCMS separation,and determination of amino acids in human plasma

March 1, 2018

Author(s)

Nino G. Todua, Johanna Camara, Jacolin A. Murray, Anzor I. Mikaia

A method for isolation of enriched fractions of amino acids from human plasma followed by derivatization, gas chromatography separation and mass spectrometry identification is described. The method involves a stepwise extraction of plasma constituents with

Evaluating droplet digital PCR for the quantification of human genomic DNA: converting copies per nanoliter to nanograms nuclear DNA per microliter

February 22, 2018

Author(s)

David L. Duewer, Margaret C. Kline, Erica L. Romsos, Blaza Toman

The highly multiplexed polymerase chain reaction (PCR) assays used for forensic human identification perform best when used with an accurately determined quantity of input DNA. To help ensure the reliable performance of these assays, we are developing a

Semiempirical Configuration Interaction Calculations for RuCentered Dyes

February 18, 2018

Author(s)

Lisa A. Fredin, Thomas C. Allison

Computational investigation of of the photochemical properties of transition-metal-centered dyes typically involves optimization of the molecular structure followed by calculation of the UV/Visible spectrum. At present, these steps are usually carried out

Examining Heat Treatment for Stabilization of the Lipidome

February 16, 2018

Author(s)

John Bowden, Candice Z. Ulmer, Christina Jones, Tracey Johnston, Jeremy P. Koelmel, Timothy J. Garrett, Richard A. Yost

Aim: To confidently determine lipid-based biomarkers, it is important to minimize variation introduced during preanalytical steps. We evaluated reducing variation associated with lipid measurements in invertebrate sentinel species using a state-of-the-art

Reverse and Random Decoy Methods for False Discovery Rate Estimation in High Mass Accuracy Peptide Spectral Library Searches

February 2, 2018

Author(s)

Zheng Zhang, Meghan C. Burke, Yuri A. Mirokhin, Dmitrii V. Tchekhovskoi, Sanford P. Markey, Wen Yu, Raghothama Chaerkady, Sonja Hess, Stephen E. Stein

Spectral library searching (SLS) is an attractive alternative to sequence database searching (SDS) for peptide identification due to its speed, sensitivity, and ability to include any selected mass spectra. However, SLS does not have a widely tested and

AQUEOUS SIZE-EXCLUSION CHROMATOGRAPHY OF POLYELECTROLYTES ON REVERSED-PHASE AND HYDROPHILIC INTERACTION CHROMATOGRAPHY COLUMNS

January 12, 2018

Author(s)

Anna Caltabiano, Joe Foley, Andre Striegel

Size-exclusion separation of a water-soluble polyelectrolyte polymer, sodium polystyrene sulfonate (NaPSS), was demonstrated on common reversed-phase (C18, C4, phenyl, and cyano) and hydrophilic interaction chromatography (HILIC) columns. The effect of

Nanostructured lipid-based films for substrate-mediated applications in biotechnology

January 10, 2018

Author(s)

Minjee Kang, Mohit Tuteja, Andrea Centrone, Daniel Topgaard, Cecilia Leal

Amphiphilic in nature, lipids spontaneously self-assemble into a range of nanostructures in the presence of water. Among lipid self-assembled structures, liposomes and supported lipid bilayers have long held scientific interest for their main applications

Organic Solvent Modifier and Temperature Effects in Non-Aqueous Size-Exclusion Chromatography on Reversed-Phase Columns

January 5, 2018

Author(s)

Andre M. Striegel, Anna Caltabiano, Joe Foley

The effect of THF solvent and the mixtures of THF with a variety of common HPLC solvents (chloroform, acetone, 2-propanol, DMF, ethanol, acetonitrile and methanol) on reversed-phase stationary phase (C18, C4, phenyl and cyano) characteristics relevant to

Determination of nicotine, NNN, and NNK in a new cigarette tobacco filler Standard Reference Material (SRM 3222) and its smoke

January 1, 2018

Author(s)

Walter B. Wilson, Jeanita Pritchett, Lane C. Sander

The United States has an annual production of approximately 800 million pounds of tobacco with estimated domestic sales of around 260 billion cigarettes/year. The National Institute of Standards and Technology (NIST) has recently collaborated with the

Editorial - Happy 50th birthday CHROMATOGRAPHIA!

January 1, 2018

Author(s)

Andre M. Striegel, Debby Mangelings, Gabriella Massolini, Brett Paull, Roger Smith, Gerhard Scriba

Identification of harmful and potentially harmful contaminants in tobacco smoke produced from low- and high-nicotine cigarette tobacco fillers

January 1, 2018

Author(s)

Walter B. Wilson, Lane C. Sander

Under the Food, Drug, and Cosmetic Act (FD&C) all tobacco manufacturers and importers are required to report the levels of harmful and potentially harmful constituents (HPHCs) found in their tobacco products and tobacco smoke. Studies have reported the

FEASIBILITY OF USING THE NATIONAL MARINE MAMMAL TISSUE BANK FOR RETROSPECTIVE EXPLORATORY STUDIES OF PERFLUORINATED ALKYL ACIDS

December 26, 2017

Author(s)

Jennifer M. Lynch, Jared M. Ragland, Amanda J. Moors, Rebecca S. Pugh, Jessica L. Reiner

Perfluorinated alkyl acids (PFAAs) have been used for more than 50 years in materials such as stain-resistant treatments for paper and clothing, lubricants, and foam fire extinguishers. PFAAs are characterized by a fully fluorinated alkyl chain with a

NIST Database for the Simulation of Electron Spectra for Surface Analysis (SESSA), SRD 100, Version 2.1

December 21, 2017

Author(s)

Wolfgang Werner, Werner Smekal, Cedric J. Powell

The objective of the NIST database for Simulation of Electron Spectra for Surface Analysis (SESSA) is to facilitate quantitative interpretation of Auger-electron and X-ray photoelectron spectra (AES/XPS). The database contains physical data required to

Quantitative chemical analysis at the nanoscale using the photothermal induced resonance technique

December 19, 2017

Author(s)

Georg Ramer, Vladimir Aksyuk, Andrea Centrone

Photothermal induced resonance (PTIR) is a scanning probe technique that provides sample composition information with a lateral resolution down to 20 nm. Interest in PTIR stems from its ability to identify unknown samples at the nanoscale thanks, in first