Spectroscopy Interviews

Detecting Neurotransmitters Using SERS and SESORS

Surface-enhanced Raman spectroscopy (SERS) and surface-enhanced spatially offset Raman spectroscopy (SESORS) have been used in medical research for the detection of neurotransmitters such as melatonin, serotonin, and epinephrine. These techniques can assist in the diagnosis of neurological diseases and provide information that can lead to more effective treatment methods. Bhavya Sharma an assistant professor in the department of chemistry at the University of Tennessee (Knoxville, Tennessee), has been using SERS and SESORS to detect neurotransmitters and probe subsurface layers through the skull. Here, she describes the advantages of these techniques and how they are used in biological applications.

Infrared (IR)

The C=O Bond, Part VII: Aromatic Esters, Organic Carbonates, and More of the Rule of Three

By Brian C. Smith

Aromatic esters follow the ester Rule of Three, but each of these three peak positions is different for saturated and aromatic esters, which makes them easy to distinguish. Organic carbonates are structurally similar to esters and follow their own Rule of Three.

The C=O Bond, Part VI: Esters and the Rule of Three

By Brian C. Smith

Esters are a common and economically important functional group made by reacting an alcohol and a carboxylic acid.

The Carbonyl Group, Part V: Carboxylates—Coming Clean

By Brian C. Smith

Carboxylates are made by reacting carboxylic acids with strong bases such as inorganic hydroxides. Carboxylates contain two unique carbon–oxygen “bond and half” linkages that coordinate with a metal ion to give two strong infrared peaks, which make them easy to see.

The C=O Bond, Part IV: Acid Anhydrides

By Brian C. Smith

Acid anhydrides are unique in that they have two carbonyl groups in them. The intensity and position of their IR peaks can be used to determine which of the four types of anhydride exist in a sample.

The C=O Bond, Part III: Carboxylic Acids

By Brian C. Smith

How to spot carboxylic acids in your IR spectra


Advancing Forensic Analyses with Raman Spectroscopy

By Spectroscopy Editors

Igor K. Lednev, of the Department of Chemistry at the University at Albany, the StateUniversity of New York, has been developing the use of Raman spectroscopy for a varietyof forensic applications, including determining the age of blood stains and linking gunshot residues to specific ammunition–firearm combinations.

Detecting Pathogenic Mycoplasmas with Surface-Enhanced Raman Spectroscopy

By Spectroscopy Editors

Duncan C. Krause, of the Department of Microbiology at the University of Georgia, discusses his group’s work to establish a SERS method with silver nanorod-array substrates for detecting the pathenogenic mycoplasma that causes bronchitis and pneumonia.

Understanding Emerging Biopolymers with 2D Raman Correlation Spectroscopy

By Spectroscopy Editors

Two-dimensional (2D) Raman correlation spectroscopy is a powerful analytical technique for analyzing a system under the influence of an external perturbation. Isao Noda, of the Department of Materials Science and Engineering, at the University of Delaware and Danimer Scientific, has been developing 2D Raman correlation spectroscopy and applying it to the study of various materials, including exciting new biopolymers. He recently spoke to us about this work.

Raman Microscopy Combined with Tensile Deformation for Understanding Changes in Polymer Morphology

By Fran Adar

We show Raman spectra of polymeric fibers acquired as a function of increasing stress and temperature. With knowledge of Raman band assignments, it becomes possible to understand, in detail, the molecular changes that are responsible for polymer orientation and crystallization.

In Situ Raman Spectroscopy Monitoring of the Reaction of Sulfur Trioxide with Polyethylene Fibers in Chlorinated Solvents

By Xiaoyun Chen, Jasson Patton, Bryan Barton, Jui-Ching Lin, Michael Behr, Zenon Lysenko

The apparent reaction kinetics between SO3 and polyethylene are investigated in various halogenated solvents using in situ Raman spectroscopy with an immersion Raman probe, demonstrating the power of in situ Raman spectroscopy to monitor hazardous reactions.


Overview of High-Efficiency Transmission Gratings for Molecular Spectroscopy

By Spectroscopy Editors

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 Spectroscopy Editors

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 Spectroscopy Editors

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.

Peer-Reviewed Articles

Enhanced Protein Structural Characterization Using Microfluidic Modulation Spectroscopy

By Eugene Ma, Libo Wang, Brent Kendrick

This article introduces a new IR technique, microfluidic modulation spectroscopy (MMS), that is designed to address the needs in biotherapeutics, and presents data from measurements of commercially available proteins.

Direct Determination of Oil Content in Binary Mixtures of Peanut and Canola Oils Using Partial Least Squares and Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy

By Chloe Lewis, Ghalib A. Bello, Gerard G. Dumancas

This study presents a novel, time-efficient, and cost-effective procedure for determining the percentage of oil content in binary mixtures of peanut and canola oils.

Single-Cell ICP-MS Analysis: Quantifying the Metal Concentration of Unicellular Organisms at the Cellular Level

By Ruth Merrifield, Lauren Amable, Chady Stephan

Single-cell ICP-MS can accurately quantify the metal concentrations within individual cells, providing new information about the mean metal content and the variation within a cell population. This method is shown to be a vital tool for assessing the specific uptake of metals by ovarian cancer cells and fresh water algae.

Exploring the Applicability of Quantitative Models Based on NIR Reflectance Spectroscopy of Plant Samples

By Yuqing Yang, Li Ma, Guorong Du, Junhui Li, Yanjun Ma

The establishment of quantitative models based on the near-infrared (NIR) spectroscopic analysis of plant samples plays an important role in improving both the scope of the models and the accuracy of prediction. This technique could provide a new method for tobacco quality management and provide a new discriminant method for other agricultural products.


Call for Nominations: 2019 Emerging Leader in Molecular Spectroscopy

Spectroscopy magazine is seeking nominations for the 2019 Emerging Leader in Molecular Spectroscopy Award.

Horiba Scientific Celebrates New Facility Opening

Horiba Scientific recently celebrated the official opening of its new facility in Piscataway, New Jersey.

WITec to Host 15th International Conference on Raman Imaging

WITec’s 15th annual Confocal Raman Imaging Symposium will take place on September 24–26 in Ulm, Germany.

SpecTube – Supplier Videos


Not All Nanoparticle Analysis Challenges are Created Equal

By Laura Bush

The detection, quantitation, and characterization of nanoparticles using inductively coupled plasma–mass spectrometry (ICP-MS), and in particular using single-particle ICP-MS (SP-ICP-MS), has developed significantly in recent years. However, the difficulties involved in this type of analysis vary, depending on the composition of the nanoparticles. Martín Resano of the University of Zaragoza, together with colleagues from Ghent University, has recently developed a method for characterizing nanoparticles made from silicon dioxide (Si02), which are much more challenging to detect than those made from silver or gold. He recently spoke to us about this work.

New Atomic Spectroscopy–Based Approaches in Geochronology: An Interview with the 2018 Emerging Leader in Atomic Spectroscopy

By Spectroscopy Editors

Geochronology is an exciting area of atomic spectroscopy and earth science research. One of the goals is to answer tectonic questions, and in particular, how the crust responds to continent–continent collision. John M. Cottle, a professor of earth science at the University of California, Santa Barbara, is one of the scientists on that mission. Cottle and his research group are at the forefront of discovery in geochronology, combining both laboratory and field-based research. In particular, Cottle is a leader in the development of novel laser-ablation inductively coupled plasma–mass spectrometry (LA-ICP-MS) measurements and their application to tectonic questions in convergent orogens, which are mountain ranges formed when a continental plate crumples and is pushed upwards.

Effective Removal of Isobaric Interferences on Strontium and Lead Using Triple-Quadrupole ICP-MS

By Daniel Kutscher, Simon Lofthouse, Simon Nelms, Shona McSheehy Ducos

Unresolved interferences can lead to biased results in ICP-MS analyses. Here we describe an approach for removing those interferences using reactive gases.

Mass Spectrometry

Mass Spectrometry Techniques to Unravel the Heterogeneity of Glycoproteins

By Asif Shajaha, Parastoo Azadi

Since glycans are responsible for bioactivity, solubility, immunogenicity, and clearance rate from circulation, it is vital to have a detailed map of glycans in therapeutic glycoproteins. Detailed glycoprotein structural analysis must be able to identify the peptide sequence where the glycans are attached as well as the structure of the glycan portion, including oligosaccharide sequence and glycosyl linkages. This article details methods for mass spectrometry experiments on both released glycans (“glycomics”), as well as on intact glycopeptides (“glycoproteomics”) using electron transfer dissociation, high-energy collision dissociation, and collision-induced dissociation fragmentation pathways, which are needed to fully elucidate the structure of glycoproteins.

Gas Chromatography–Mass Spectrometry Characterization of Vegetable Oil–Derived Potent Antimicrobial Agents

By Racha Seemamahannop, Prakash Wadhawa, Shubhen Kapila, Abha Malhotra

Under a suitable thermal oxidation regime, vegetable oils yield a mixture of volatile and semivolatile organics that exhibit very high antimicrobial activities against a variety of microbial species. Volatile and semivolatile products were characterized with GC–MS using electron ionization and chemical ionization. The thermal oxidation of vegetable oils resulted in the formation of an array of short and medium-chain acids, aldehydes, and ketones that act synergistically to yield a potent antimicrobial disinfectant.

Review of the 65th 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 4–8 in Indianapolis, Indiana.

lorem ipsum