Interview of the Month

FT-IR Microscopy with High Spatial Resolution

Advances in spatial resolution for Fourier transform infrared (FT-IR) imaging historically have involved the use of a synchrotron source, but new optics have been developed that yield better spectral quality and spatial resolution than are provided by existing synchrotron sources. Kathleen Gough, Professor in the Department of Chemistry at the University of Manitoba, has been working with her group to conduct diagnostic tissue imaging with the new thermal source FT-IR system. She recently spoke to us about these efforts.

Quantum Mechanics

This series of installments from David Ball’s excellent “Baseline” column discusses the relevance of quantum mechanics for spectroscopy and why it is important for spectroscopists to know the basics.


Read more.

FT-IR

FT-IR Microscopic Analysis of Polymer Laminate Samples Including Transmission and ATR Spectroscopy

By Richard A. Larsen, Ken-ichi Akao, Jun Koshoubu, Kohei Tamura, Hiroshi Sugiyama

The value of combining ATR and transmission spectra for the analysis of polymer laminates is illustrated here through the analysis of a multilayer polymer laminate from a food packaging sample.

Purity Analysis of Adulterated Essential Oils by FT-IR Spectroscopy and Partial-Least-Squares Regression

By Brianda Elzey, Victoria Norman, Jamira Stephenson, David Pollard, Sayo O. Fakayode

This study explores the use of FT-IR spectroscopy and PLS regression for the authentication of essential oils—wintergreen oil, tea tree oil, rosemary oil, and lemon eucalyptus oil—adulterated with either lemongrass oil or peppermint oil.

Vibrational Spectroscopic DiscrimiVibrational Spectroscopic Discrimination of Herbal Medicines: Polygala senega, Polygala tenuifolia, and Glinus oppositifolius

By Cornelia K. Pezzei, O.M.D. Lutz, V.A. Huck-Pezzei, Sarah Kuderer, Brigitte Kopp, Christian W. Huck

A simple and rapid authentication method is presented for herbal medicine samples using commercially available mid-infrared and near-infrared benchtop spectrometers as well as using a handheld NIR device.

The Benzene Fingers, Part I: Overtone and Combination Bands

By Brian C. Smith

We explain the theory behind the three different types of IR bands, how to recognize them, and how to use them to help you interpret spectra.

Distinguishing Structural Isomers: Mono- and Disubstituted Benzene Rings

By Brian C. Smith

There are three ways of arranging two substituents around a benzene ring, meaning that each disubstituted ring has three structural isomers. Fortunately, infrared spectroscopy can distinguish such structural isomers. Here, we explain how.

Raman

Using SERS to Study How Cells Respond to Pharmaceuticals

By Spectroscopy Editors

Colin Campbell discusses his work applying SERS to biomedical applications.

Polarized Raman Spectroscopy of Aligned Semiconducting Single-Walled Carbon Nanotubes

By Amir Mashal, Dick Wieboldt, Katherine Jinkins, Michael S. Arnold

A look at how polarized Raman imaging can be used to characterize alignment in large regions of aligned semiconducting carbon nanotube films.

Recent Developments in Handheld Raman Spectroscopy for Industry, Pharma, Forensics, and Homeland Security: 532-nm Excitation Revisited

By Aleksandr V. Mikhonin, Susan Hodi, Laurence A. Nafie, Rina K. Dukor

Handheld Raman using 532-nm excitation is an effective option for field analysis, in applications ranging from the analysis of biopharmaceuticals to explosive detection.

Raman Spectroscopy as a Tool for Analytical Quality Control in a Hospital Environment

By Karen A. Esmonde-White

Two applications of Raman spectroscopy in a hospital environment are reviewed: analytical quality control for compounded formulations and gas analysis during general anesthesia.

UV-vis

Overview of High-Efficiency Transmission Gratings for Molecular Spectroscopy

By Thomas Rasmussen

This article provides a basic overview of the capabilities of transmission gratings optimized for molecular spectroscopy.

Scattering Impact Analysis and Correction for Leaf Biochemical Parameter Estimation Using Vis–NIR Spectroscopy

By Qianxuan Zhang, Qingbo Li, Guangjun Zhang

Simulated leaf spectral data were generated to analyze scattering impact and then compared to experimental data to validate the conclusions of the simulation.

An Integration of Modified Uninformative Variable Elimination and Wavelet Packet Transform for Variable Selection

By Di Wu, Xiaojing Chen, Yong He

The wavelet packet transform (WPT) combined with the modified uninformative variable elimination (MUVE) method (WPT–MUVE) is proposed to select variables for multivariate calibration of spectral data.

Analysis of Fructose, Glycine, and Triglycine Using HPLC UV-vis Detection and Evaporative Light-Scattering Detection

By A.B. de Haan, R. Wijntje, H.A.J.M. Bevers

The development of a method for the simultaneous determination of glycine, triglycine and fructose using UV–vis and evaporative light-scattering detection (ELSD) is described. This was necessary as part of a research project dealing with the recovery of functional peptides from aqueous streams on an industrial scale using adsorption or related technologies. Fructose is barely detectable by UV–vis as it lacks detectable functionalities, while glycine and triglycine are both UV–vis sensitive. An NH2 phase was chosen as a column and separation was obtained within seven minutes on a 250 X 4.6 mm column. Limits of detection are approximately 40 mg fructose/L, 4 mg glycine/L and 0.05 mg triglycine/L. Calibration functions are linear in a range of 40–1400 mg/L for fructose, 5–200 mg/L for glycine and 0.5–70 mg/L for triglycine.

Spectroscopy in Space: Hubble and the Cosmic Origins Spectrograph

By Spectroscopy Editors

In an upcoming spacewalk, shuttle astronauts will swap the Corrective Optics Space Telescope Axial Replacement (COSTAR) device for the new Cosmic Origins Spectrograph (COS).

Peer-Reviewed Articles

Emerging Trends and Opportunities in Discrete-Frequency Infrared and Raman Spectroscopic Imaging

By Tomasz P. Wrobel, Matthew R. Kole, Rohit Bhargava

Recent advances in instrumentation have enabled new forms of vibrational chemical imaging, including discrete-frequency infrared (DFIR) microscopy and stimulated Raman scattering (SRS) microscopy. These technologies may represent a fundamental shift in how we approach spectroscopic imaging.

Preparation of Pharmaceutical Samples for Elemental Impurities Analysis: Some Potential Approaches

By Nancy Lewen

As analysts prepare to meet the requirements of the new United States Pharmacopeia and International Conference on Harmonization standards on elemental impurities, they need to understand how to choose the most suitable sample preparation approach.

News

Indiana University School of Informatics and Computing Awarded $1M Grant from NIH

The National Institutes of Health (NIH) has awarded $1.18 million to faculty at the Indiana University School of Informatics and Computing at Indiana University–Purdue University Indianapolis and the IU School of Medicina (Indianapolis, Indiana) for a research collaboration that unites two cutting-edge technologies in the discovery and analysis of proteoforms.

Proceeds from Pittcon 2016 Award Grants to Fund Science Education Grants at the Elementary, High School, and College Levels

Proceeds from Pittcon 2016 are distributed by its sponsoring societies, the Society for Analytical Chemists of Pittsburgh (SACP), and the Spectroscopy Society of Pittsburgh (SSP).

Spectroscopy at Analytica

Analytica 2016, held this week in Munich, includes strong programming in spectroscopy techniques. Two sessions—one on modern analytical spectroscopy and another on bioprocessing monitoring—are entirely dedicated to spectroscopy.

ICP/ICP-MS

What Modeling Reveals About the Properties of an Inductively Coupled Plasma

By Spectroscopy Editors

Annemie Bogaerts and Maryam Aghaei of the University of Antwerp, Belgium, are carrying out computational modeling to examine how various properties of the ICP, such as gas flow path lines and ionization effects, are affected by various factors—such as gas flow rates, applied power, and even the very presence of a mass spectrometry sampler. Using their developed model, one can predict optimum conditions for specific analyses.

How to Improve Analytical Figures of Merit of Hard-To-Ionize Elements in ICP-Based Techniques

By Spectroscopy Editors

Matrix effects in ICP-OES and ICP-MS often cause signal suppression, but can lead to signal enhancement as well. Guillermo Grindlay of the University of Alicante, in Spain, discusses his work to better understand under what conditions these matrix effects occur and what mechanisms are involved.

Questioning the Relationship Between Analyte Ion Mass and ICP-MS Matrix Effects

By Spectroscopy Editors

New studies conducted by Shi Jiao and John Olesik at The Ohio State University have important implications for understanding the fundamental causes of matrix effects in ICP-MS, and for the choice of internal standards.

Determining Trace Elements in Edible Oils Using Inductively Coupled Plasma–Optical Emission Spectrometry

By Manuel Almeida, Karolina Carpenter

During the processing of edible oils, the analysis of trace metals, which can promote oxidation, is important. This article presents a study of metals in edible oils using radial-view ICP-OES and discusses the most suitable wavelengths, background correction, and integration times.

Sample Preparation Method for Mercury Analysis in Reagent Chemicals by ICP-OES

By Yogesh Parikh, Samantha Mahmoud, James Lallo, Huifang Lang

This study shows that a direct Au3+ and HCl sample preparation method quickly and simply allows for accurate Hg quantification by ICP-OES in a wide range of sample types.

Mass Spectrometry

Review of the 64th Conference on Mass Spectrometry and Allied Topics

By Cindy Delonas

We present a brief review of this year's ASMS conference, which took place June 5–9 in San Antonio, Texas.

Sensitive, Rapid Estimation of Moxidectin in Cattle Hair by LC–MS-MS

By P. Sambasivarao, Raman Batheja, N. Subbarao, S. Ashma, K. Ashwini, M. Mupeksha

Validation of this rapid bioanalytical method for the determination of moxidectin in cattle hair demonstrated that the method is accurate, reliable, and reproducible.

The Applicability of Field-Portable GC–MS for the Rapid Sampling and Measurement of High-Boiling-Point Semivolatile Organic Compounds in Environmental Samples

By Tai Truong, Nathan Porter, Ed Lee, Robert J. Thomas

A look at the use of field-portable GC–MS with solid-phase microextraction, purge-and-trap, thermal desorption, and heated headspace sampling techniques to provide a fast response for in-field analysis of SVOCs in a wide variety of environmental-type samples including potable waters, tea, plants, and road gravel.

Comparison of LC–MS and GC–MS for the Analysis of Pharmaceuticals and Personal Care Products in Surface Water and Treated Wastewaters

By Blake Rushing, Ashley Wooten, Marcus Shawky, Mustafa I. Selim

This study of a selected group of PPCP contaminants in eastern North Carolina demonstrates the advantages and disadvantages of LC–MS and GC–MS as well as SPE and liquid–liquid extraction.

Review of the 64th Conference on Mass Spectrometry and Allied Topics

By Cindy Delonas

We present a brief review of this year's ASMS conference, which took place June 5–9 in San Antonio, Texas.

lorem ipsum